A PPENDIX I
H YDROLOGY AND W ATER Q UALITY
......
...... WATER SUPPLY ASSESSMENT FOR THE NAPA PIPE PROJECT NAPA COUNTY, CALIFORNIA
AUGUST 25, 2011
WATER SUPPLY ASSESSMENT FOR THE NAPA PIPE PROJECT NAPA COUNTY, CALIFORNIA
REVISED AUGUST 25, 2011
PREPARED BY
WITH TECHNICAL ASSISTANCE BY
WATER SUPPLY ASSESSMENT FOR THE NAPA PIPE PROJECT
TABLE OF CONTENTS
SECTION 1 EXECUTIVE SUMMARY ...... 1 1.1 Purpose and Scope of the Water Supply Assessment...... 1 1.2 The Project...... 2 1.3 Water Purveyor...... 3 1.4 Water Demands...... 3 1.5 Water Supplies...... 4 1.5.1 Groundwater ...... 5 1.5.2 Imported Surface Water Supplies ...... 10 1.5.3 Recycled Water Supplies ...... 11 1.5.4 City of Napa Water Supplies ...... 14 1.6 Comparison of Water Supplies and Demands ...... 16 SECTION 2 BACKGROUND ...... 18 2.1 Description of the Project ...... 18 2.2 Climate...... 21 2.3 Water Purveyor...... 23 2.4 Legal Requirements ...... 26 SECTION 3 WATER DEMANDS...... 30 3.1 Historical and Current Water Demands...... 30 3.2 Demands in Normal, Single Dry and Multiple Dry Water Years...... 31 3.3 Water Quality...... 31 3.4 Projected Water Demands...... 31 3.5 Water Efficiency Strategies ...... 33 3.6 Phasing of Projected Water Demands...... 34 SECTION 4 LOCAL GROUNDWATER SUPPLIES...... 36 4.1 Basin Description and Applicable Technical Studies...... 36 4.1.1 California Department of Water Resources...... 36 4.1.2 United States Geological Survey ...... 38 4.1.3 Napa County...... 39 4.1.4 City of Napa...... 40 4.1.5 Investigation for the Project...... 41
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4.2 Local Groundwater Conditions...... 42 4.2.1 Occurrence of Groundwater...... 42 4.2.2 Historical and Existing Wells ...... 43 4.2.3 Historical Pumping and Water Levels ...... 44 4.2.4 Recent Field Investigations...... 47 4.2.5 Groundwater Quality...... 49 4.3 Groundwater Rights...... 50 4.3.1 Legal Classification of Groundwater...... 50 4.3.2 Groundwater Rights...... 50 4.3.3 Overlying Groundwater Rights...... 51 4.3.4 Appropriative Groundwater Rights...... 52 4.3.5 Basin Management...... 53 4.3.6 County Groundwater Policies and Ordinances...... 54 4.4 Hydraulic Separation of the Sonoma Volcanics Aquifer...... 56 4.5 Groundwater Supply Estimate ...... 58 4.6 Other Local Groundwater Users ...... 58 4.6.1 City of Napa...... 59 4.6.2 City of American Canyon ...... 60 4.6.3 Vineyards ...... 61 4.6.4 Syar Industries Quarry ...... 61 4.6.5 Kennedy Park Golf Course ...... 62 4.6.6 Summary of Groundwater Users ...... 62 4.7 Groundwater Level Impact Analysis ...... 62 4.8 Interaction with Milliken-Sarco-Tulucay Basin ...... 63 4.9 Groundwater Monitoring and Mitigation Plan ...... 65 4.10 Impact of Climate Change on Local Groundwater...... 66 4.11 Reliability Assessment...... 68 SECTION 5 IMPORTED SURFACE WATER...... 71 5.1 Imported Surface Water...... 71 5.2 Laws Affecting Water Right Assignment and Change...... 71 5.3 The Mill Creek Water Source...... 72 5.3.1 Background Information and Description of Water Source ...... 72
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5.3.2 Option Agreement...... 81 5.3.3 Mill Creek Water Resources...... 81 5.3.4 Mill Creek Biological Resources...... 83 5.3.5 Yield of the NRP Water Right...... 89 5.3.6 Approach to Making Water Available...... 92 5.3.7 Other Sources of Water...... 94 5.4 Diversion of Water at SWP Facilities...... 96 5.4.1 Introduction to the Delta ...... 96 5.4.2 Delta Water Infrastructure and Barker Slough Diversions...... 96 5.4.3 General Condition of the Delta and Various Threats...... 100 5.4.4 Environmental Litigation...... 105 5.4.5 Delta Planning Processes ...... 105 5.4.6 Water Conveyance Losses ...... 110 5.5 Water Conveyance...... 114 5.5.1 Infrastructure...... 114 5.5.2 Conveyance Through SWP Facilities ...... 123 5.5.3 Agreement with the Cities ...... 124 5.6 Impacts of Climate Change on Imported Surface Water...... 125 SECTION 6 RECYCLED WATER ...... 130 6.1 Napa Sanitation District...... 130 6.1.1 Overview of Napa Sanitation District...... 130 6.1.2 Strategic Plan...... 131 6.1.3 MST Area Project ...... 132 6.1.4 North Bay Water Recycling Program...... 133 6.1.5 Delivery of Recycled Water Within the City of Napa Water Service Area...... 135 6.1.6 Service to the Napa Pipe Project...... 136 6.2 On-Site Wastewater Treatment Plant...... 137 6.2.1 Basic Description...... 137 6.2.2 Reliability Assessment...... 139 SECTION 7 CITY OF NAPA WATER SUPPLIES...... 140 7.1 City of Napa Service Area ...... 140
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7.1.1 Boundaries ...... 140 7.1.2 Population and Demographics Within CON Service Area...... 142 7.2 Water Demands...... 143 7.2.1 Historical Water Use by Customer Type...... 143 7.2.2 Demand Projection and Methodology ...... 145 7.2.3 Projected Water Use by Customer Type...... 147 7.2.4 Deliveries to Other Agencies...... 148 7.2.5 Other Proposed Development Projects ...... 148 7.2.6 Demand Management ...... 150 7.3 Water Supplies...... 156 7.3.1 Milliken Reservoir...... 156 7.3.2 Lake Hennessey...... 157 7.3.3 State Water Project...... 158 7.3.4 Other Potential Water Sources...... 165 7.3.5 Total Supply Projections...... 166 7.4 City Water Supplies v. Demands...... 167 7.5 City Water System Hydraulic Impacts and Infrastructural Analysis...... 172 7.5.1 Storage Evaluation...... 172 7.5.2 Analysis of Existing Water Distribution System...... 173 7.5.3 Analysis of Future Water Distribution System...... 174 7.5.4 Required New City Infrastructure to Serve the Project ...... 175 SECTION 8 AVAILABILITY OF SUFFICIENT SUPPLIES ...... 177
TABLES
Table ES-1. Projected Water Demands for the Project...... 4 Table ES-2. NSD Recycled Water Supplies and Demands (AFY) ...... 12 Table ES-3. Recycled Water Availability from Onsite Treatment Plant...... 14 Table ES-4. Comparison of Water Supplies and Demands for the Project (2010-2030) ...... 16 Table 1. Project Land Uses ...... 17 Table 2. Irrigated Areas ...... 20 Table 3. Average Climate Data for City of Napa ...... 21 Table 4. Projected Potable Water Demands for the Napa Pipe Project...... 31 iv AUGUST 25, 2011
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Table 5. Projected Non-Potable Water Demands for the Napa Pipe Project...... 32 Table 6. Projected Non-Potable Water Use by Phase for the Napa Pipe Project ...... 33 Table 7. Projected Potable Water Use by Phase for the Napa Pipe Project...... 34 Table 8. Lithology of Deep Wells on the Project Site ...... 42 Table 9. Groundwater Production Wells Drilled in the Suscol Area...... 44 Table 10. Groundwater Production at the Project Site (1989-2005) ...... 45 Table 11. Impact on Observation Points During Constant Rate Aquifer Test...... 48 Table 12. Baseline and Projected Future Increased Pumping, Suscol Area ...... 58 Table 13. Groundwater Level Impact from Pumping of Sonoma Volcanics Aquifer...... 62 Table 14. Historical Annual Yields of the Mill Creek Water Right (AF) ...... 91 Table 15. NSD Recycled Water Supply, Demand and Surplus Under NBWRP (2020)...... 136 Table 16. NSD Recycled Water Supplies and Demands ...... 138 Table 17. Recycled Water Availability from Onsite Treatment Plant...... 139 Table 18. Projected Population of the City of Napa ...... 144 Table 19. City of Napa Historical Accounts by Customer Type ...... 145 Table 20. City of Napa Historical Demand by Customer Type...... 145 Table 21. City of Napa Total Projected Water Demands (2005-2050) ...... 148 Table 22. City of Napa Projected Water Demands by Customer Type...... 148 Table 23. Projected Potable Water Demands from Future Projects in City of Napa Water Service Area...... 151 Table 24. City of Napa Water Shortage Stages of Action ...... 155 Table 25. City of Napa Supply Action Trigger Levels...... 155 Table 26. City of Napa Annual Consumption Limit by Stage and Customer Group ...... 156 Table 27. Milliken Reservoir Yield ...... 158 Table 28. Lake Hennessey Yield ...... 159 Table 29. City of Napa SWP Table A Entitlement Schedule ...... 161 Table 30. State Water Project Reliability Assessments...... 164 Table 31. City of Napa Projected SWP Deliveries...... 165 Table 32. City of Napa Total Water Supplies (2010-2030 ...... 167 Table 33. City of Napa Water Supplies Under Various Hydrologic Conditions...... 168 Table 34. City of Napa Water Supplies and Demands ...... 169 Table 35. Projected Population and Water Demands of the City of Napa ...... 173
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Table 36. State Water Project Reliability Assessments (2009) ...... 175 Table 37. Summary of Flow from Each City Storage Tank to Meet Buildout Demand Conditions (2030) ...... 178 Table 38. Comparison of Water Supplies and Demands for the Project (2010-2030) ...... 181
FIGURES
Figure 1. Project Location...... 18 Figure 2. Project Site Plan ...... 19 Figure 3. Groundwater Basins Map...... 36 Figure 4. Mill Creek General Location...... 74 Figure 5. Mill Creek Water Diversion and Conveyance Facilities...... 78 Figure 6. Photos of Runyon Dam and Ditch...... 79 Figure 7. Historical Yield of the Mill Creek Water Right ...... 90 Figure 8. Exceedance Curve for the Mill Creek Water Right...... 90 Figure 9. Sacramento-San Joaquin Delta Area Map...... 97 Figure 10. DSM2-Simulated Tidal Flows (cfs) and Tidal Volumes (AF) for Lindsey Slough Upstream of Cache Slough for March 2001 ...... 99 Figure 11. Geologic Map of Lower Mill Creek Area ...... 111 Figure 12. City of American Canyon Daily Surface Water Use...... 117 Figure 13. American Canyon’s Conveyance Capacity...... 119 Figure 14. Conceptual Water Operations Under Two Scenarios...... 121 Figure 15. Process for Gaining Access to Water Conveyance Infrastructure...... 126 Figure 16. City of Napa Water Service Area...... 142
EXHIBITS
Hydroscience Engineers, Inc., Napa Pipe Project, Water And Wastewater Feasibility Study (January 2011) ...... A City of Napa, City of Napa 2005 Urban Water Management Plan Update (January 2006)...... B Stetson Engineers, Inc., Groundwater Report: Former Napa Pipe Corporation (August 31, 2009)...... C West Yost & Associates, 2050 Napa Valley Water Resources Study (October 2005)...... D West Yost & Associates, Technical Memorandum: Feasibility Level Evaluation of the Groundwater Supply Available from the Napa Pipe Corporation Facility for Use as a Municipal Supply, Project No. 424-02-05-03.01 (August 16, 2005)...... E
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F. Kunkel and J.E. Upson, Geology and Groundwater in Napa and Sonoma Valleys, Napa and Sonoma Counties, California, Geological Survey Water Supply Paper 1495 (1960)...... F C.D. Farrar and L.F. Metzger, Ground-Water Resources in the Lower Milliken-Sarco- Tulucay Creeks Area, Southeastern Napa County, California 2000-2002, United States Geological Survey Water-Resources Investigations Report 03-4229 (2003)...... G Montgomery Watson, Suscol Production Well and Deep Aquifer Characterization Report, Napa Pipe Corporation, Napa, California (October 1993)...... H Decree, Los Molinos Land Company v. Cloughs, Tehama County Sup. Ct., No. 3811 ...... I Napa Sanitation District, Strategic Plan for Recycled Water Use in the Year 2020 (August 2005) ...... J Napa Sanitation District, Board of Directors Materials (June 17, 2009)...... K Brownstein Hyatt Farber Schreck, LLP, Reasoned Legal Opinion re Wastewater Service for Napa Pipe Project (August 14, 2009)...... L West Yost & Associates, Technical Memorandum: Task 1: Water Demand and City Water System Hydraulic Impacts, Project No. 424-02-07-05 (August 21, 2008) ...... M Brownstein Hyatt Farber Schreck, LLP, A Survey and Summary of Climate Change Reports (August 2011)...... N
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ABBREVIATIONS
ABAG ...... Association of Bay Area Governments AF ...... acre-feet AFY...... acre-feet per year Agreement...... Option and Agreement for Assignment of Water Right AmCan ...... City of American Canyon ASR...... aquifer storage and recovery BDCP ...... Bay Delta Conservation Plan bgs...... below ground surface BiOp...... biological opinion BMP ...... best management practice CEQA...... California Environmental Quality Act CESA ...... California Endangered Species Act cfs...... cubic feet per second CON ...... City of Napa Conservancy...... Mill Creek Conservancy Council...... Delta Stewardship Council County...... County of Napa CPUC ...... California Public Utilities Commission CUWCC...... California Urban Water Conservation Council CVP...... Central Valley Project Delta...... Sacramento-San Joaquin Delta DFG...... California Department of Fish and Game DRMS ...... Delta Risk Management Study DSM2...... Delta Simulation Model Version 2 DWR ...... California Department of Water Resources DWSC...... Sacramento Deep Water Ship Channel EIR ...... environmental impact report ESA...... Endangered Species Act ETo...... evapotranspiration FEIR...... final environmental impact report gpcd...... gallons per capita per day gpd...... gallons per day gpm ...... gallons per minute GHG...... greenhouse gas GMMP ...... groundwater monitoring and mitigation plan HCP...... Habitat Conservation Plan viii AUGUST 25, 2011
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HSE...... Hydroscience Engineers, Inc. IPCC...... Intergovernmental Panel on Climate Change KCWA ...... Kern County Water Agency LAFCO ...... Napa County Local Agency Formation Commission LMMWC...... Los Molinos Mutual Water Company MCWEP...... Mill Creek Water Exchange Program MGD ...... million gallons per day msl...... mean sea level MST ...... Milliken-Sarco-Tulucay NBA ...... North Bay Aqueduct NBWRA...... North Bay Water Reuse Authority NBWRP ...... North Bay Water Recycling Program NCAR ...... National Center for Atmospheric Research NCCP ...... Natural Community Conservation Plan NCFCWD ...... Napa County Flood Control & Water Conservation District NEPA ...... National Environmental Policy Act NMFS...... National Marine Fisheries Service NPDES...... National Pollutant Discharge Elimination System NRP...... Napa Redevelopment Partners, LLC NSD...... Napa Sanitation District OCID...... Orange Cove Irrigation District POA...... property owners association Project ...... Napa Pipe Project psi...... pounds per square inch RPA...... Reasonable and Prudent Alternatives RUL...... Rural Urban Limit Boundary SB 610...... California Senate Bill 610 SC...... Specific Conductance SCWA...... Solano County Water Agency Stetson...... Stetson Engineers, Inc. SWP ...... State Water Project SWRCB...... California State Water Resources Control Board SWRF...... Soscol Water Recycling Facility TDS...... total dissolved solids USBR ...... United States Bureau of Reclamation USFS...... United States Forest Service USFWS ...... United States Fish and Wildlife Service USGS ...... United States Geological Survey
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UWMP ...... urban water management plan VAMP...... Vernalis Adaptive Management Plan Wheeling Statutes ...... California Water Code §§ 1810 et seq. Workplan...... 2006 Strategic Workplan for the Delta WSA...... Water Supply Assessment for the Napa Pipe Project WTP ...... water treatment plant WWTP ...... wastewater treatment plant WYA...... West Yost & Associates
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SECTION 1 EXECUTIVE SUMMARY
1.1 Purpose and Scope of the Water Supply Assessment
The purpose of this water supply assessment (“WSA”) is to provide an evaluation of the adequacy of total existing and future water supplies available to serve the Napa Pipe Project (“Project”) currently proposed for redevelopment in Napa County, California by Napa Redevelopment Partners, LLC (“NRP”). This WSA has been prepared for review and approval by the County of Napa (“County”) in accordance with the requirements of California Water Code §§ 10910 et seq., commonly referred to as California Senate Bill 610 (“SB 610”).
SB 610 established the primary legal standards for assessing the sufficiency of water supplies for new development projects. These statutes require that as part of the environmental review conducted for a qualifying project pursuant to the California Environmental Quality Act (“CEQA”), the relevant public water supplier or land use agency—in this case the County—must prepare a “water supply assessment” of the reliability of water supplies for the project, considering normal, single dry and multiple dry years over a 20-year horizon. The basic requirement is that a water supply assessment must “include a discussion with regard to whether the public water system’s total projected water supplies available during normal, single dry, and multiple dry water years during a 20-year projection will meet the projected water demand associated with the proposed project, in addition to the public water system’s existing and planned future uses, including agricultural and manufacturing uses.”1
This WSA follows the publication of two public review documents: the Water Supply Assessment for the Napa Pipe Project, Napa County, California, dated October 15, 2009; and the Supplement to the Water Supply Assessment for the Napa Pipe Project, Napa County, California, dated January 19, 2011. This WSA contains all information included in those two documents, as well as additional information in response to public comments received on them. Because this WSA represents the combination of the two prior documents, some of the section numbers have changed, but the contents are largely the same. This WSA generally refers to the discussions contained herein rather than to the prior documents.
In the following sections, this WSA discusses the sources of water that will be available to the Project for the first 20 years of the development and beyond. Section 1 is this Executive Summary. Section 2 describes the Project and general background for this WSA. Section 3 contains historical, current and projected water demands for the Project site, including the anticipated demands of the Project. Sections 4 through 6 describe existing and projected water supply sources that will be available to serve the Project, including groundwater (Section 4), imported surface water (Section 5) and recycled water (Section 6). While it is the intention of NRP and the County to utilize local groundwater, imported surface water and recycled water to meet the water demands of the Project, Section 7 describes the water supplies of the City of Napa (“CON”) as requested by that agency. Section 8 provides a summary of supply sufficiency for the Project.
1 See Section 2.4; CAL. WATER CODE § 10910(c)(3). Unless otherwise noted, all references to numbered sections, tables, figures or footnotes are to those items as found in this WSA. AUGUST 25, 2011 1
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This WSA also contains a number of exhibits, as follows:
• Exhibit A is a technical report prepared by Hydroscience Engineers, Inc. (“HSE”) that discusses the water and wastewater utility systems that will be designed, constructed and operated for the Project. It is incorporated into this WSA.
• Exhibit B is a copy of the 2005 Urban Water Management Plan (“CON UWMP”) adopted by CON for its water utility.
• Exhibit C contains a technical evaluation of local groundwater supplies prepared by Stetson Engineers, Inc. (“Stetson”) and is incorporated into the WSA.
• Exhibits D through H are previous studies related to local groundwater supplies, prepared by West Yost & Associates (“WYA”), the United States Geological Survey (“USGS”) and Montgomery Watson.
• Exhibit I is a court decree in the water rights adjudication of Los Molinos Land Company v. Cloughs, Tehama County Superior Court, Action No. 3811.
• Exhibit J is a strategic plan adopted by the Napa Sanitation District (“NSD”) regarding its recycled water operations, and Exhibit K is a collection of board materials from that agency.
• Exhibit L is a reasoned legal opinion from the law firm of Brownstein Hyatt Farber Schreck, LLP concerning the formation of a private sewer company.
• Exhibit M is a technical memorandum prepared by WYA for CON evaluating its water system and necessary infrastructure improvements to serve the Project.
• Exhibit N is a survey and summary of technical reports related to climate change and water resources, and is incorporated into this WSA.
1.2 The Project
The Project consists of an approximately 154-acre redevelopment located within Napa County and adjacent to the southern limits of CON. Historically, the Project site has been used as a well field for groundwater exports to Benicia, Crockett and Vallejo and for heavy industrial activities. Onsite water demands have been met by local groundwater pumped from wells on the site and, since the 1950s, a connection to the CON water utility.
NRP proposes to redevelop the site for mixed use consisting of 2,580 attached residential dwelling units in multi-story buildings, 150 senior housing units, 15,000 square feet of restaurant space, 25,000 square feet of retail space, 50,000 square feet of office space, 140,000 square feet of industrial, research and development or warehousing space, various community facilities and
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a 150-room condominium hotel. The Project will include parks and public open space, including a community garden.2
1.3 Water Purveyor
NRP is the developer of the Project, but as with most developments, NRP will not provide water utility service once the Project has been completed. Upon construction of each Project phase, ownership and operation of all water utility systems will be transferred to a qualified water purveyor. While the Project site is located within CON’s water service area, and CON has historically provided and currently provides water to the Project site for industrial purposes, NRP and CON have not reached agreement regarding the terms and conditions under which CON would provide water service to the Project. Therefore, it is unknown at this time who will be the water purveyor for the Project.
There are five alternatives for the water purveyor, each of which is considered in this WSA: a new or existing investor-owned public utility company; a mutual water company; a special public district; CON; or the City of American Canyon (“AmCan”). All five types are currently being considered by NRP, although for purposes of this WSA, it is assumed that existing CON water supplies will not be utilized. Based on a request by CON, however, this WSA does evaluate the sufficiency of CON water supplies to serve the Project. Importantly, the type of water purveyor used will not have any significant impact on the availability of the water resources described in this WSA.3
1.4 Water Demands
In this WSA, the water demands of the Project are divided into potable and non-potable because the Project will utilize different sources of water based on the differing water quality requirements of Project demands. Specifically, indoor water uses for residential and commercial spaces, such as water for drinking, cooking and sanitation, require water treated to potable standards, while irrigation of exterior spaces may utilize high quality recycled water that does not meet potable standards. California state law encourages the use of recycled water whenever it is available and of adequate quality and reasonable cost, in order to conserve and optimize use of the state’s valuable water resources. The Project will seek to promote that important policy by using recycled water to meet the demands of landscape irrigation.4
Recorded historical water use on the Project site has been as high as 1,230 acre-feet per year (“AFY”). Recent historical water use at the Project site has averaged approximately 150 AFY of groundwater, plus an additional amount purchased from the CON water utility.5 As shown in Table ES-1, based on analyzing the water demands of each component of the Project, projected potable and non-potable water demands are approximately 620 and 141 AFY, respectively.6
2 See Section 2.1. 3 See Section 2.3. 4 See Section 3.3. 5 See Section 3.1. 6 See Section 3.4 and 3.5.
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Table ES-1. Projected Water Demands for the Project7 Quality Phase 1 Phase 2 Phase 3 Total Potable 235 190 195 620 Non-Potable 51 64 26 141
In order to evaluate water supply reliability, SB 610 requires the consideration of water supplies and demands in normal, single dry and multiple dry water years. There is no statute or regulation that dictates the proper method for calculating demands in single dry and multiple dry water years, and no consistent approach has been developed by water resource professionals within the state. This WSA does not include any reduction in water demands for single dry or multiple dry water years when compared to normal water years because of a desire to be conservative in the WSA’s overall approach to water supply reliability planning.8
1.5 Water Supplies
The Project will rely upon three sources for water: local groundwater and imported surface water to meet potable demands, and recycled water to meet non-potable demands. Although the Project does not plan to rely on water supplies from CON, in comments related to the scoping of environmental review for the Project, CON requested that the WSA analyze the feasibility of CON serving the Project. In respose to that request, the WSA evaluates the current and future water supplies and demands of CON and its ability to serve the Project.
The Project intends to rely on both local groundwater and imported surface water to meet the potable water demands of the Project. Based on a peer-reviewed expert analysis, this WSA concludes that the Sonoma Volcanics aquifer underlying the Project site contains sufficient groundwater resources to meet all water demands of the Project (620 AFY) on a sustainable long-term basis, without having any significant impact on other existing or foreseeable future groundwater users, including those in the Milliken-Sarco-Tulucay (“MST”) area. This conclusion is based on historical levels of groundwater pumping, the sources and rate of recharge and aquifer characteristics derived from a 2008 testing program, as described below.
In addition to local groundwater, the Project intends to use imported surface water when it is available. The Project applicant has secured the right to substantial surface water rights in the Sacramento River system and plans to convey that water to the Project site by working cooperatively with the Napa County Flood Control and Water Conservation District (“NCFCWD”), AmCan, CON and California Department of Water Resources (“DWR”), which are the entities with interests in the Napa County portion of the North Bay Aqueduct and local water conveyance facilities. Based on expert analysis, this WSA concludes that given a conservative set of assumptions, it is likely that the water purveyor could import between 456 and 620 AFY of surface water to the Project. As described in this WSA, Section 5.5, the Project will need to obtain approval or agreement from several entities prior to being able to convey imported water to the Project. The Project applicant will exercise best efforts to gain all such approvals and agreements and will use imported surface water when available, so that the Project
7 See Table 4, Table 5, Table 6 and Table 7. 8 See Section 3.2. 4 AUGUST 25, 2011
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does not use substantially more groundwater on average than extractions from the Project site in recent years, i.e., 150 AFY. To the extent imported surface water is not available, the Project will rely entirely on local groundwater.
1.5.1 Groundwater
The first source of potable water for the Project will be local groundwater underlying the Project site. The property overlies the Sonoma Volcanics aquifer of the Napa Valley Subbasin, which serves as a natural underground reservoir for local water supplies. This WSA analyzes the physical availability of groundwater for the Project from that aquifer, as well as the legal and institutional mechanisms that control use of the resource.
Based on the analysis contained in this WSA, the Project may develop up to approximately 620 AFY of groundwater for the Project, which would satisfy all Project demands. The Project will have sufficient water rights to groundwater based on correlative overlying rights associated with the Project site. The groundwater investigation was conducted by Stetson; peer review was provided by Luhdorff & Scalmanini Consulting Engineers. The investigation concluded that the target aquifer system, i.e., the Sonoma Volcanics, can reliably produce at least 3,100 AFY on a long-term basis, which is sufficient to meet the full needs of the Project as well as other identified groundwater users in the surrounding Suscol area. Use of groundwater for the Project is not expected to injure other nearby groundwater users or those in the MST area.
1.5.1.1 Technical Review
Prior technical reports concerning the Sonoma Volcanics aquifer were reviewed for purposes of this WSA. In addition, a hydrogeological investigation of groundwater resources underlying the Project site was conducted by Stetson.
Relying on the Stetson Report, this WSA evaluates the availability and reliability of groundwater resources primarily in the southern Napa Valley Subbasin, referred to as the Suscol area. According to the California Department of Water Resources (“DWR”), in its Bulletin 118-80 (1980), the Napa Valley Subbasin did not experience overdraft conditions at that time. More recently, a review of historic groundwater levels (dating from 1930 to 2002) in wells located in the Napa Valley between the cities of Calistoga and Napa concluded that groundwater levels throughout the Napa Valley appeared to be stable.9
Declining groundwater levels have occurred, however, to the northeast of the Project site in the MST area, which partially overlaps the Napa Valley Subbasin on its eastern side. While the Project site is not located within the MST area, this WSA evaluates the connection between the Sonoma Volcanics aquifer underlying the Project site and the water-bearing formations in the MST area, and the effect that groundwater extractions for the Project would have on groundwater availability in the MST area and vice versa. In addition, this WSA evaluates the effects that groundwater extractions for the Project would have on the southern Napa Valley Subbasin in the Suscol area and on other currently existing and potential future groundwater users in the surrounding Suscol area.
9 See Section 4.1. AUGUST 25, 2011 5
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The Stetson Report based its evaluation of groundwater underlying the Project site on a review of all previously published studies and data related to the Napa Valley Subbasin, the Suscol area and the MST area. In addition, Stetson performed three field investigations to gather additional information about the characteristics of the Sonoma Volcanics aquifer and groundwater underlying the Project site: a passive groundwater level monitoring program and water quality analysis performed in 2007; construction and testing of a new deep well (NRP-01) in 2008; and measuring of groundwater levels in 2009. Based on information contained in prior reports and the new data gathered in field investigations, Stetson (i) analyzed the connection between groundwater underlying the Project site and the Napa River, (ii) estimated the quantity of groundwater available in the Suscol area of the southern Napa Valley Subbasin on a sustainable long-term basis due to groundwater inflow and recharge, and (iii) estimated the impacts of groundwater extractions for the Project on groundwater levels at several locations chosen to represent other groundwater users and the boundary of the MST area.10
1.5.1.2 The Sonoma Volcanics Aquifer
There are several layers of groundwater-bearing materials underlying the Project site, the shallowest of which is the younger alluvium, existing to a depth of approximately 3 to 20 feet below ground surface. Below the younger alluvium, there is the older alluvium, which exists between approximately 30 and 130 feet below ground surface on the Project site, with some areas reaching as deep as 350 feet. Underlying the younger and older alluvium layers is a clay layer that effectively prevents the upward or downward movement of groundwater. Below that clay layer is a water-bearing geological formation known as the Sonoma Volcanics.
The Sonoma Volcanics create a regional aquifer that is present in the Napa River, Sonoma Creek and Petaluma River watersheds. The Sonoma Volcanics include lava flows, tuffs, debris flows, lacustrine sediments and sedimentary volcanic rocks. Groundwater within these geologic formations exists under artesian (confined) conditions in the Project area, meaning that the groundwater elevation as measured by pressure is higher than the top of the aquifer. Such artesian conditions have been reported historically and continue to exist today. An artesian aquifer is, by definition, fully saturated, and when the confining layer overlying the aquifer is penetrated by a well, water will rise through the well to the aquifer’s groundwater elevation without pumping. According to one recent technical study prepared for the County, the Sonoma Volcanics “are permeable and host significant volumes of water.”11
The Sonoma Volcanics aquifer has been used extensively for groundwater development on the Project site and in the Suscol area. Beginning in the early 1900s, deep wells on the Project site were used to extract groundwater for various municipal and industrial uses. Groundwater pumping was as high as 1,230 AFY (in 1949-1950) during the most active period of industry on the Project site, and averaged 150 AFY during the recent period from 1989 through 2005. Despite this extensive use of groundwater, the Sonoma Volcanics aquifer remained artesian at all times, and groundwater levels rose quickly when groundwater extractions were reduced.12
10 See Sections 4.1.5 and 4.2.4. 11 See Section 4.2.1. 12 See Sections 4.2.2 and 4.2.3. 6 AUGUST 25, 2011
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1.5.1.3 Groundwater Rights
In order for the Project to rely on groundwater, the water purveyor for the Project will need to possess a legal right to access that groundwater. In addition, it is important that the groundwater basin be properly managed for groundwater to serve as a reliable long-term supply, and groundwater rights serve as the basis for most management of groundwater resources. For these reasons, the WSA analyzes the groundwater rights that will be relied upon for the Project. Groundwater rights in California may be of two basic types: overlying and appropriative. The Project will rely on overlying rights, but could also establish appropriative rights if needed in future.
The owner of real property overlying a groundwater aquifer possesses a right as part and parcel of the land to extract groundwater from beneath the property for use on overlying land within the watershed. The overlying right consists of a present right to use water for existing and prospective beneficial uses. The right may remain unexercised or dormant, unless a court adjudication provides otherwise. An overlying owner’s groundwater right is correlative with all other overlying users’ rights, which means that the overlying owner is entitled to extract and use a proportional and reasonable share of the common supply. Absent a court adjudication of groundwater rights, the overlying owner is not limited to any specific quantity of water because, by definition, the amount of water to which the overlying owner is entitled fluctuates with the present beneficial needs of the landowner.
The owners of the Project site have been using groundwater pursuant to overlying rights since the early 1900s. Thus, those overlying rights are well established and cannot be argued to have been lost through prescription to any other overlyer or appropriator. Because water rights in the Sonoma Volcanics aquifer remain unadjudicated, the right of the Project site to pump water from the formation is not governed by any court order or agreement. In addition, no groundwater management plan has been adopted by any agency. Thus, the basin is currently unregulated. A groundwater permit will be acquired for the Project pursuant to the Napa County groundwater ordinance.13
1.5.1.4 Available Groundwater Supply
The Sonoma Volcanics aquifer in the Suscol area is supplied with groundwater from two sources: groundwater inflow from the north and direct recharge from outcroppings to the east. In order to estimate the supply of available groundwater in the Suscol area for the Project and other water users, Stetson calculated the amount of groundwater inflow and recharge for the Suscol area.
To quantify the northern groundwater inflow into the Sonoma Volcanics aquifer in the Suscol area, Stetson calculated a hydraulic gradient using groundwater levels representing developed conditions. A cross-section area calculation was used to estimate the groundwater inflow that occurs in the upper 500-feet of the aquifer, yielding a conclusion that at least 2,700 AFY of subsurface flow is available to the Suscol area. In addition to groundwater inflows, the amount of groundwater available to the site is dependent on local recharge originating as rainfall in the Howell Mountains located on the eastern side of the Napa Valley. This recharged groundwater
13 See Section 4.3. AUGUST 25, 2011 7
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flows from the Howell Mountains westward toward the center of the Napa Valley, moving down beneath the fine grained clay aquitard of the deeper older alluvial deposits into the confined Sonoma Volcanics aquifer beneath the Suscol area.14 Recharge from the eastern mountains is estimated to equal at least 400 AFY.
Based on the calculations above, the combined supply of groundwater from both northern inflows and local recharge available in the Sonoma Volcanics aquifer in the Suscol area is at least 3,100 AFY. This is the quantity of water that can likely be extracted from the Sonoma Volcanics aquifer on the Project site on a long-term basis, without producing any adverse effects. The combined water demands of current groundwater users within the Suscol area are 910 AFY, while total projected future groundwater use (including existing uses, the Project and anticipated future uses by others) is 1,660 AFY. Thus, under current conditions there is a surplus of at least 2,190 AFY, and under future pumping conditions there is projected to be a surplus of at least 1,440 AFY. Groundwater pumping within the Suscol area is not expected to exceed 55 percent of the available groundwater supply.15
1.5.1.5 Impact on Other Groundwater Users
This WSA analyzes the potential impact of groundwater extractions for the Project on other groundwater users, and vice versa. The impact of projected pumping to meet the water demands of the Project on groundwater levels at the location of other groundwater users in the Suscol area ranges from 1.0 to 1.2 feet, while pumping at those locations impacts groundwater levels at the Project site by a range from less than 0.1 to 1.3 feet. These projected drawdowns are very small and considered insignificant.16
1.5.1.6 Impact on the MST Area
The Stetson Report and this WSA address an identified concern for groundwater in Napa County, namely, the MST area. While the MST area is not located within the Napa Valley Subbasin (except for a small area of overlap not within the Suscol area), the County requires that all new developments proposing to use groundwater in the general vicinity address the potential for impacts to and by groundwater users in the MST area.
The MST area is located off the eastern side of the Napa Valley in a topographic depression that is enclosed on the north, east and south by the Howell Mountains and bounded on the west by the Napa River. The MST area is recharged by precipitation that infiltrates in the Howell Mountains and then flows to the west into the MST area, and a much smaller amount of groundwater inflow from the Napa Valley Subbasin on the northwestern side of the MST area. Based on increases during the period since 1975 in groundwater extractions by landowners within the MST area, that area is generally experiencing groundwater level declines and has developed three groundwater level depressions. Those depressions have caused reduced groundwater outflows from the MST area into the Napa Valley Subbasin, but have not impacted groundwater levels in the Suscol area or the Project site due to significant and independent sources of recharge there.
14 An aquitard is a layer of relatively impervious materials, in this case a clay layer that effectively prevents the flow of water both downward and upward between the shallow alluvium and deep volcanics. See Section 4.4. 15 See Section 4.5. 16 See Sections 4.6 and 4.7. 8 AUGUST 25, 2011
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In order to evaluate the impact that groundwater extractions in the Suscol area by the Project and other identified groundwater users might have on the MST area, two nearby wells were chosen to represent the areas of interest regarding potential impacts—one located at the Project site and one located south of the MST area at the location of the Smith Brown Well No. 1, which is approximately 4,700 feet northeast of Well NRP-01. Using the aquifer characteristics determined during the 2008 aquifer test, Stetson estimated that at most groundwater pumping for the Project would draw down groundwater at the Smith Brown Well No. 1 by 3.4 feet, which is very small and considered insignificant. The impact on the Smith Brown Well No. 1 from the projected cumulative pumping of all groundwater users in the Suscol area would be at most 4.0 feet. Thus, cumulative extractions by all groundwater users in the Suscol area, including the Project, would not have a significant impact on the Smith Brown Well No. 1 and even less on the MST area to the north.
Based on this analysis, the Stetson Report and this WSA conclude that proposed groundwater extractions for the Project, considered individually and as part of the cumulative pumping of all current and future groundwater users within the Suscol area, would have no measurable effect on groundwater supplies in the MST area.17
1.5.1.7 Conclusion
There are a number of factors that lead to the conclusion that the groundwater resources of the Sonoma Volcanics aquifer in the Suscol area will be sufficient to meet the potable water demands of the Project over a 20-year planning horizon, in normal, single dry and multiple dry years.
• Groundwater has been extracted from the Sonoma Volcanics aquifer underlying the Project site since the early 1900s without negative impacts on groundwater supplies or other users.
• Historical data indicate that as much as 1,230 AFY of groundwater was produced from the Project site, which is approximately double the groundwater production required for the Project.
• From 1989 through 2005, groundwater production at the Project site averaged 150 AFY, and groundwater levels remained artesian and approximately at the ground surface.
• The Sonoma Volcanics aquifer in the Suscol area receives groundwater inflow from the north at a rate of at least 2,700 AFY, and direct recharge from the east at a rate of at least 400 AFY, for a combined supply of at least 3,100 AFY. Both of these sources are dependent on long-term multi-year trends rather than short term hydrologic conditions.
• Projected future groundwater pumping from all landowners and users in the Suscol area, including the Project, equals approximately 1,660 AFY, which is less than 55 percent of the total annual groundwater supply.
17 See Section 4.8. AUGUST 25, 2011 9
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• The impact of groundwater production at the Project site on the closest other groundwater user would be at most 1.2 feet of drawdown, which is insignificant and will not cause any injury to other groundwater users.
• The hydrogeology of the MST area varies from that of the Suscol area because of the different sources of recharge and historical overpumping of the MST area, neither of which affects the Suscol area.
• Increased groundwater extractions for the Project are projected to lower groundwater levels in the Smith Brown Well No. 1 between 1.0 and 2.0 feet. That well is located south of the boundary of the MST area, and such an impact on groundwater levels would not be significant. Cumulative groundwater extractions for the Project and all other groundwater users in the Suscol area are projected to lower groundwater levels in that well by approximately 3.1 feet, which is small and considered insignificant.
Based on these factors, groundwater from the Sonoma Volcanics aquifer underlying the Project site is determined to be available to meet all potable water demands (620 AFY), in addition to other existing and future uses of groundwater, including agricultural and manufacturing uses. This conclusion applies for the 20-year planning horizon of this WSA in normal, single dry and multiple dry years.18
1.5.2 Imported Surface Water Supplies
This WSA analyses the availability of imported surface water supplies based on a water right located on Mill Creek, a tributary to the Sacramento River, which would be acquired by NRP from the Orange Cove Irrigation District (“OCID”) pursuant to an option agreement between the two entities. The acquired right has been adjudicated and would be capable of making available approximately 1,900 AFY on average, which is more than enough to satisfy all demands of the Project. In order to change the identified water right from its current use to use for the Project, OCID, NRP and the eventual water purveyor would implement an assignment and change of water rights according to California law.19
In order to convey water from the water right’s current point of diversion on Mill Creek to the Project, the water would utilize the natural channel of Mill Creek, the Sacramento River, the Sacramento-San Joaquin Delta (“Delta”), Barker Slough,20 the Barker Slough Pumping Plant, the North Bay Aqueduct and the water distribution system of either AmCan or CON. Assuming use of the AmCan distribution system, existing water infrastructure is capable of conveying between 456 and 620 AFY of surface water to the Project, depending on water demands within AmCan. Additional water demands of the Project would be met by producing between 0 and 164 AFY of local groundwater, which is roughly equal to or less than recent historical groundwater production at the Project site. Data is not available to calculate the specific quantity of water that could be conveyed by CON to the Project, but it is known that some capacity is not fully utilized by CON and might be made available to the Project.
18 See Section 4.11. 19 See Section 5.3. 20 See Section 5.4. 10 AUGUST 25, 2011
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In order to provide value to AmCan or CON (or both) for their services in conveying water from Barker Slough to the Project, NRP may assign the unneeded portion of the Mill Creek water right described above to the cities for use within their respective water service areas. Such a water supply could be used by the cities to increase the reliability of their respective portfolios of water sources in light of declining reliability of their State Water Project and other water entitlements, or could be used for other purposes that are currently unidentified and would be specified by the cities in the future.21
Based on the analysis in Section 5, this WSA concludes that imported surface water would likely be available for the Project in varying amounts up to the full Project water demands of 620 AFY. In conjunction with local groundwater, imported surface water supplies are projected to be sufficient to meet all Project water demands during normal, single dry and multiple dry years over a 20-year horizon.
1.5.3 Recycled Water Supplies
The Project will also use recycled water from either NSD or a wastewater treatment plant (“WWTP”) to be constructed on the Project site to meet all demands of the Project for landscape irrigation water, which are projected to be approximately 141 AFY. Either of those recycled water supplies is available for the first 20 years of the Project and beyond.
1.5.3.1 Napa Sanitation District
Under the first alternative, the Project would purchase recycled water from NSD to meet non- potable irrigation water demands. This alternative may or may not include wastewater from the Project being collected and treated by NSD. Under that latter scenario, NSD would collect wastewater inflows from the Project, as well as other areas within the NSD service area, and deliver that wastewater to the Soscol Water Recycling Facility (“SWRF”), which NSD owns and operates south of CON and the Project site.22
The SWRF currently produces approximately 8.8 million gallons per day (“MGD”) of disinfected tertiary recycled water, which is of sufficient quality to use for purposes of irrigation at the Project. During the irrigation season, when NSD is prohibited from discharging any effluent to the Napa River, and the recycled water demands of the Project and other NSD customers is greatest, NSD has the ability to produce approximately 3,590 AFY of recycled water using its current infrastructure. Based on wastewater inflows from the Project, the SWRF could produce another 283 AFY during those critical months. In 2005, the most recent year for which NSD has reported its recycled water sales, NSD delivered approximately 1,184 acre-feet (“AF”) to its customers.23 NSD considers new recycled water uses to be reasonable when located within 0.25 miles of a recycled water pipeline, as is the case for the Project site. The district considered the Project site as the location of possible industrial use in its strategic plan, and that use could easily be modified to landscape irrigation based on construction of the Project.
NSD has undertaken several planning efforts regarding the expansion of its recycled water deliveries. First, as part of its Strategic Plan for Recycled Water Use in the Year 2020 adopted in
21 See Section 5.5. 22 See Section 6.1. 23 See Section 6.1.1. AUGUST 25, 2011 11
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2005, NSD estimated that the SWRF in 2020 could produce up to 9,800 AFY of tertiary-treated recycled water. The district’s stated long-term goal is to recycle all water produced at the SWRF, if funding is available for the capital facilities needed to store and distribute the water.24 Second, NSD has also proposed to deliver recycled water to the MST area, in order to help alleviate groundwater stress within that area. Studies have found potential use of recycled water for that purpose could range from 350 AFY to 2,304 AFY, with associated capital costs ranging from $13.5 million to $47.5 million, respectively.25 Third, NSD is participating in the regional North Bay Water Recycling Program (“NBWRP”), which includes the use of recycled water from the SWRF being used in the MST area.26
In order to obtain recycled water for the Project, NRP or the Project water purveyor will need to negotiate and execute a recycled water supply agreement with NSD. Such an agreement has not yet been negotiated, but NSD has expressed a desire to collect and treat wastewater from the Project and supply recycled water to the Project. In addition, the NSD planning documents discussed above indicate a desire to expand sales of recycled water where feasible, including the Project site. There do not appear to be substantial reasons why the Project applicant or the water purveyor would not be able to successfully negotiate and execute an agreement with NSD. Accordingly, recycled water is considered a highly likely and reliable water supply for the Project.
Table ES-2. NSD Recycled Water Supplies and Demands (AFY)27 2020 Alternatives Stand-Alone MST Project NBWRP
2005 No MST Project MST 50/40 Project MST 100/100 Project Expressed Interest MST Project Alternative 1 Alternative 2 Alternative 3 Existing Service Area Demands 1,184 2,598 2,598 2,598 2,598 2,598 2,598 2,598 MST Service Area Demands 0 0 1,175 2,304 351 3,192 4,421 4,421 Total Projected Demands 1,184 2,598 3,773 4,902 2,949 5,590 7,019 7,019 Projected Supplies 3,590 9,800 9,800 9,800 9,800 9,800 9,800 9,800 Surplus Recycled Water 2,406 6,338 6,027 4,898 6,851 3,841 2,657 2,657
All of the NSD planning documents discussed in this WSA demonstrate that sufficient recycled water will be available to serve the Project. As shown in Table ES-2, those documents project that recycled water supplies in 2020 and following years will be at least 9,800 AFY, whereas demands will be a maximum of 2,598 without an MST area project. Because the Project site is
24 See Section 6.1.2. 25 See Section 6.1.3. 26 See Section 6.1.4. 27 See Table 16. 12 AUGUST 25, 2011
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located within NSD’s current recycled water service area, the demands of the Project are included within that 2,598 figure. In addition, there is sufficient surplus recycled water available under every alternative in the NSD planning documents to meet the Project demands without impacting the availability of recycled water to other potential users. Because recycled water supplies do not vary significantly according to hydrologic conditions, NSD recycled water supplies would be available to the Project across normal, single dry and multiple dry year types.28
1.5.3.2 Onsite Wastewater Treatment Plant
An alternative to the Project purchasing recycled water from NSD is to site and construct a wastewater treatment plant within the Project area. At this location, the wastewater treatment plant could receive wastewater flows from the Project, treat them to tertiary levels and pump back recycled water into the Project’s recycled water system for non-potable uses. If an onsite wastewater treatment plant is utilized for the Project, it will be owned and operated by a private sewer company. That sewer company would be organized as either an investor-owned, public utility company or a non-profit mutual benefit corporation. The sewer company could be combined with a private water company, if such an entity is formed to serve as the water purveyor described in Section 2.3 of this WSA.
According to the analysis in this WSA, approximately 10 percent of the Project’s indoor water usage is estimated to be consumptive and the remaining 90 percent of wastewater flows would be conveyed to the wastewater collection and treatment system. At the end of Phase 1 of the Project, the average daily wastewater flows are projected to be 197,000 gallons per day (“gpd”). After Phase 2, the average daily flows are projected to be 351,000 gpd. At build out, the average daily flow from the Project is projected to be 505,000 gpd.
Recycled water will be delivered to the Project’s park and public landscaping areas through a recycled water piping system. At build out, the peak day irrigation demand for recycled water is projected to be 259,000 gpd, which is 51 percent of recycled water production from the onsite wastewater treatment plant. In other words, the treatment plant can produce approximately twice as much recycled water than is required by the Project on the peak day. Thus, there will be sufficient supplies of recycled water to meet the irrigation demands of the Project. The same will be true for the Project after Phase 1, when 197,200 gpd of wastewater will be available to meet peak day demands of 93,800 gpd, and after Phase 2, when 351,000 gpd of wastewater will be available to meet peak day demands of 211,000 gpd.29 Recycled water supplies and demands are shown in Table ES-3.
28 See Section 6.1.6. 29 See Section 6.2.1.
AUGUST 25, 2011 13
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Table ES-3. Recycled Water Availability from Onsite Treatment Plant30 After Phase 1 After Phase 2 After Phase 3 Recycled Water Supply 197,000 351,000 505,000 Peak Day Demand 94,000 211,000 259,000 Surplus (Deficit) 103,000 140,000 246,000
Based on the analysis in this WSA and the technical report prepared by HSE (Exhibit A), there do not appear to be substantial reasons why NRP would not be able to successfully construct an onsite wastewater treatment plant and re-use the tertiary treated water on-site for landscape irrigation at the Project. Accordingly, recycled water created from the Project’s own supply of wastewater at an onsite wastewater treatment plant is considered a highly feasible and reliable water supply for the Project, and represents a co-equal option to purchasing recycled water from NSD.31
1.5.4 City of Napa Water Supplies
CON has requested that this WSA and the environmental review for the Project evaluate the possibility of CON water service to the Project. CON is not expected to supply water for the Project or be the water purveyor, although the Project site is located within CON’s designated water utility service area, and NRP is a current water customer of CON.
CON obtains its water supplies from three surface water sources: Milliken Reservoir, Lake Hennessey, and the State Water Project (“SWP”). Conclusions about the reliability of CON water supplies to serve existing and future water demands, as well as the projected demands of the Project, require a comparison of water supplies and demands across hydrologic year types for the first 20 years of the Project. Section 7 compares total water supplies and demands of CON, and calculates the amount of surplus or deficit in those water supplies for the defined year types, both with and without the Project.
As analyzed in Section 7, CON has a surplus of water under normal and multiple dry years, both with and without the Project. Thus, CON’s total projected water supplies available during those year types will meet the projected water demand associated with the Project, in addition to CON’s existing and planned future uses, including agricultural and manufacturing uses. During single dry years, CON is currently projected to experience water supply deficits through 2025 and small surpluses beginning in 2030 without the Project. In those single dry years, provision of water service to the Project by CON would increase the size of the city’s deficit or turn a surplus into a small deficit by the amount of Project water demands.
Several factors affect the sufficiency of CON water supplies to meet the combined demands of existing CON customers, future growth in CON and the Project.
• The planning assumptions used by CON, and relied on in this WSA, tend to overestimate water demands and underestimate water supplies.
30 See Table 17. 31 See Section 6.2.2. 14 AUGUST 25, 2011
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• Past CON actions have achieved short-term reduction in water demands as needed by just over 31 percent, which in future would be sufficient to eliminate the deficit in all projected years, including the water demands of the Project.
• CON has access to additional water not reflected above in certain years, based on carryover of SWP entitlement water from prior years, purchase of so-called Article 21 water, and purchase of water from special dry year supply programs.
• CON has expressed interest in obtaining additional surface water supplies in dry years, and has had discussions with potential sellers of water rights. In addition, CON could develop local groundwater supplies, such as those underlying the Project site.
In its planning documents, CON has concluded that it will have sufficient water supplies in future to meet the demands of customers in its water service area, despite the presence of a temporary deficit when comparing projected demands and firm supplies in single dry years. CON reached that conclusion based on the potential actions it could take to correct any deficit, as described above. Based on these actions, CON is projected to be able to supply water to all its water customers, including the Project as a potential customer, during single dry years over a 20- year horizon and beyond.32
In addition, this WSA describes several improvements to CON’s water infrastructure that might be required to serve the Project. The following summarizes what have been determined to be the new water system infrastructure that would be required for CON to provide potable water service to the Project:
• A new treated water storage facility with a total useable capacity of approximately 2.5 million gallons to provide for operational, fire flow and emergency storage for the Project and associated pump station which would allow this tank to be integrated into CON’s system, depending on the location of the storage facility;
• Incremental pumping capacity increase of 1 MGD (from 19.4 to 20.4 MGD) for the proposed new Westside Pump Station in the southwestern portion of CON’s distribution system in order to provide for adequate system pressures during peak hour demand conditions at buildout; and
• Incremental treatment capacity increase of 1 MGD (from 20 to 21 MGD) at the Jamieson Canyon Water Treatment Plant (“WTP”).33
1.6 Comparison of Water Supplies and Demands
As described in this WSA, potable water demands of the Project are projected to be approximately 620 AFY, and non-potable demands will be approximately 141 AFY. A comparison of water demands and proposed supplies for the Project are shown in Table ES-4. This table assumes that Phase 1 of the Project will be constructed between 2010 and 2015, and Phases 2 and 3 will be constructed between 2015 and 2020.
32 See Section 7.4. 33 See Section 7.5. Note that this analysis of the City’s infrastructure was based on an earlier, larger iteration of the Project; therefore, the water system improvements described in this discussion are likely to be oversized. AUGUST 25, 2011 15
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Based on the analysis above, this WSA concludes that the public water system to be constructed for the Project will have water supplies available during normal, single dry and multiple dry water years during a 20-year projection to meet the all water demands associated with the proposed Project, and will not adversely affect the availability of water for any other use, including agricultural and manufacturing uses.34
Table ES-4. Comparison of Water Supplies and Demands for the Project (2010-2030) 2010 2015 2020 2025 2030 Potable Water Surface Water Supplies(a) 456 456 456 456 456 Groundwater Supplies 3,100 3,100 3,100 3,100 3,100 Project Demands (235) (620) (620) (620) (620) Other GW Demands(b) (1,037) (1,037) (1,037) (1,037) (1,037) Surplus (Deficit) 2,484 1,899 1,899 1,899 1,899 Non-Potable Water – NSD Alternative Recycled Water Supply(c) 3,590 3,590 9,800 9,800 9,800 Project Demands (51) (141) (141) (141) (141) Other User Demands(d) (1,184) (1,184) (7,019) (7,019) (7,019) Surplus (Deficit) 2,355 2,265 2,657 2,657 2,657 Non-Potable Water – Onsite WWTP Alternative Recycled Water Supply 393 566 566 566 566 Project Demands (51) (141) (141) (141) (141) Surplus (Deficit) 342 425 425 425 425 All figures expressed in AFY. (a) Imported surface water figures are based on minimum water conveyance in the Maximum Year Scenario per Section 5.5.1. Water supplies on Mill Creek are much larger, with a minimum of 1,177 AF in the historical record and an average of 1,900 AF, after reducing for 12 percent conveyance losses. Thus, the limiting factor on imported water supplies for the Project is conveyance capacity, rather than water rights. (b) This table assumes that all existing and identified future water demands of other users are currently in place. (c) This analysis assumes that NSD will implement its Strategic Plan starting in 2020; if that assumption is not fulfilled, recycled water supplies and demands from 2020-2030 will match those shown in 2015. (d) This represents the maximum water demands of all potential users of recycled water from NSD, which includes the Project starting in 2020.
34 See Section 8. 16 AUGUST 25, 2011
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SECTION 2 BACKGROUND
2.1 Description of the Project
The Project consists of an approximately 154-acre redevelopment located within the County of Napa and adjacent to the southern limits of the CON. The site is bounded on the west by the Napa River, on the south by Bedford Slough, on the east by the extension of Syar Industrial Way and on the north by Kaiser Road. The Project is located outside of the CON limits. The general location of the Project is shown in Figure 1.
Historically, the Project site has been used for heavy industrial activities, including shipbuilding and steel pipe manufacturing. NRP proposes to redevelop the site for mixed use consisting of 2,580 attached residential dwelling units in multi-story buildings, 150 senior housing units, 15,000 square feet of restaurant space, 25,000 square feet of retail space, 50,000 square feet of office space, 140,000 square feet of industrial, research and development or warehousing space, and a 150-room condominium hotel. The Project will include parks and public open space. The site plan is shown in Figure 2, and the specific uses of Project site lands are listed in Table 1.
Table 1. Project Land Uses Percent of Land Use Area (sq ft) Area (acres) Site Residential and Mixed-Use Buildings 1,050,947 24.1 15.6 Residential Surface Parking Lots 258,346 5.9 3.8 Industrial/Commercial Buildings 560,475 12.9 8.3 “White Space” 594,699 13.7 8.8 Building and Surface Lots Subtotal 2,464,467 56.6 36.7 Sidewalks 566,849 13.0 8.4 Main Roadways and Street Parking 868,624 19.9 12.9 Carriage Ways 234,647 5.4 3.5 Transportation Pathways Subtotal 1,670,119 38.3 24.9 Rear Yards 141,230 3.2 2.1 Podium Over Parking 275,034 6.3 4.1 Landscaping at Industrial & Commercial Blocks 62,275 1.4 0.9 Private Open Space Subtotal 478,539 11.0 7.1 Parks and Wetlands 1,710,867 39.3 25.5 Other Landscaped Areas (Sidewalks, Front Yards) 395,953 9.1 5.9 Public Open Space Subtotal 2,106,820 48.4 31.4
Grand Total 6,719,945 154.3 100.0 Source: Napa Redevelopment Partners, LLC
AUGUST 25, 2011 17
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Figure 1. Project Location
18 AUGUST 25, 2011
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Figure 2. Project Site Plan
AUGUST 25, 2011 19
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The Project is a planned green community with significant open space and many water conservation components. For example, recycled water will be used to irrigate common areas such as parks and street landscaping. All irrigated open space areas are listed in Table 2, and as can be seen, the vast majority of those lands will be irrigated with recycled water. Other water conservation measures to be implemented for the Project are discussed in Section 3.5 of this WSA.
Table 2. Irrigated Areas Irrigated Irrigated Landscaping Total Area Area Area Description Type† (sq ft) (sq ft) (acres) Areas Irrigated with Potable Water Rear Yards TST 141,230 98,861 2.27 Community Gardens TST 20,000 20,000 0.46 Subtotal 161,230 118,861 2.73 Areas Irrigated with Recycled Water Front Yards NP 293,286 175,971 4.04 Curbside Biodetention Areas NP 102,667 102,667 2.36 Open Parking Lots NP 258,346 38,752 0.89 Wetland Setback Areas NP 280,584 238,496 5.48 Wetlands NP 206,562 0 0.00 Subtotal 1,141,445 555,886 12.77 Parks TST 1,183,079 999,158 22.94 Podium Over Parking TST 275,034 192,524 4.42 Landscaping at Industrial & TST 62,275 62,275 1.43 Commercial Blocks Subtotal 1,520,388 1,253,957 28.79 Grand Total 2,823,063 1,928,704 44.29 Source: Napa Redevelopment Partners, LLC. † TST = turf, shrubs and trees; NP = native plants.
2.2 Climate
The Napa Valley climate is similar to the Mediterranean region, characterized by hot dry summers and cooler wet winters.35 The 91-year average annual precipitation in the Valley is 24.68 inches, ranging from a low of 9.52 inches in 1924 to a high of 50.24 inches in 1983. The
35 Hydroscience Engineers, Inc., Napa Pipe Project, Water and Wastewater Feasibility Study, at § 4.1.1 (August 2009) (“HSE Report”) [Exhibit A]; City of Napa, Urban Water Management Plan 2005 Update, at 2-3 (January 17, 2006) (“CON UWMP”) [Exhibit B]. 20 AUGUST 25, 2011
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median (50th percentile of ranked values) is 22.83 inches.36 Greater amounts of precipitation occur in the higher elevations of the surrounding Mayacmas and Howell Mountains than in the lower valley adjacent to San Pablo Bay.37 As described in Section 4.5 of this WSA, groundwater levels in the Sonoma Volcanics aquifer underlying the Project site are affected by long-term precipitation in the Howell Mountains, but are not significantly affected by the amount of precipitation in any given year. The impact of climate change on Project water supplies is discussed in Section 4.10 below.
Table 3 below summarizes relevant climate data, including average monthly maximum and minimum temperatures, precipitation and evapotranspiration (“ETo”), which represents the irrigation needs of standard cool-season turfgrass in Napa. More than 70 percent of annual ETo occurs in the months of May through September. This drives the demand for supplemental irrigation as these months have the lowest rainfall totals. Typically July, August and September are rainless. There is, however, considerable variation in precipitation from year to year. An annual total of less than 13 inches can be anticipated one year out of 20, while more than 36 inches can be expected with about the same frequency. Annual precipitation averages over 20 inches, but approximately 80 percent of that total falls in the months of November through March, when plant water needs are at their lowest.
Table 3. Average Climate Data for City of Napa Maximum Minimum Precipitation ETo Temperature Temperature (inches per (inches per Month (°F) (°F) month) month) January 57.5 37.9 2.56 0.82 February 61.9 40.5 3.21 1.49 March 65.7 41.7 2.01 3.09 April 70.0 43.3 1.19 4.57 May 74.8 47.2 0.75 5.46 June 80.0 51.1 2.17 6.61 July 82.0 53.0 0.00 6.89 August 81.9 52.8 0.00 6.18 September 82.2 51.2 0.05 4.71 October 76.6 47.5 0.57 3.52 November 66.3 42.2 2.67 1.41 December 57.9 38.5 6.59 1.02 Annual 71.4 45.6 21.78 45.77 Source: HSE Report, at Table 4-1 [Exhibit A]; CON UWMP, at Table 2-2 [Exhibit B].
36 Stetson Engineers, Inc., Groundwater Report, Former Napa Pipe Corporation, at 2-1 (August 31, 2009) (“Stetson Report”) [Exhibit C]. 37 Id. AUGUST 25, 2011 21
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Mild temperatures predominate in Napa, but highs in excess of 100°F have been observed at one time or another in every month from May through October. Nights cool off quickly. The average minimum temperature during the summer months is in the low 50s. Winter brings subfreezing temperatures nearly every year. Historically, temperatures below 32°F have been recorded during each month from October through May. During the winter, daily temperatures climb into the upper 50s on average.
Under the influence of the nearby mountains and the flow of air through San Pablo Bay, wind direction is from the southwest most of the time and average speed is relatively light. Relative humidity average values during the summer may be around 60 percent, while in the winter they reach nearly 80 percent. Afternoon readings during most of the year will average 45 to 55 percent, while in the early morning hours the humidity will range from 80 to 90 percent. ETo is somewhat affected by temperature, wind and humidity, but the primary driving force is simply the amount of sunlight. Long summer days mean higher ETo and more landscape irrigation.38
2.3 Water Purveyor
NRP is the developer of the Project, but as with most developments, NRP will not provide retail water utility service once the Project has been completed. Upon construction of each Project phase, ownership and operation of all water utility systems will be transferred to a qualified water purveyor. While CON currently provides water to the Project site for industrial purposes, NRP and CON have not reached agreement regarding the terms and conditions under which CON would provide water service to the Project. Therefore, it is unknown at this time who will be the water purveyor for the Project. This section discusses several options that are available.
First, NRP could form or work with an existing investor-owned public utility company. Such privately-owned public utility companies may provide water service and, in fact, currently serve approximately 20 percent of all water customers in California.39 One small investor-owned water utility currently operates in Napa County.40 Such a company would not be subject to the jurisdiction of the Napa County Local Agency Formation Commission (“LAFCO”), but would be subject to comprehensive regulation by the California Public Utilities Commission (“CPUC”) and be required to meet numerous standards for water service quality, including the management of water resources. Because the Project site is not currently within the service territory of any public water utility, a proposed company would need to acquire a certificate of public convenience and necessity from the CPUC for the Project site.41 With the support of NRP as the Project developer, it would be likely that a public utility could obtain such a certificate.42
38 CON UWMP, at 2-4 [Exhibit B]. 39 See CAL. PUB. UTIL. CODE §§ 216, 2701. 40 See County of Napa, Napa County General Plan Update Draft Environmental Impact Report, at 4.13-35 (February 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&exturl=http://www.napacountygeneral- plan.com/], finalized in County of Napa, Napa County General Plan Final Environmental Impact Report, State Clearinghouse No. 2005102088 (December 20, 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&- exturl=http://www.napacountygeneralplan.com/]. 41 See CAL. PUB. UTIL. CODE § 1001. 42 The factors relied upon by the CPUC when determining whether a certificate should be granted include the preference of the developer, and past experience suggests that when a developer supports the public utility, a certificate is normally granted. See Re Great Oaks Water Co., 39 CPUC 2d 339, 345-46 (Cal. P.U.C. 1991); Application of Bakman Water Co., 1 CPUC 2d 364, 373-376 (Cal. P.U.C. 1979). 22 AUGUST 25, 2011
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Second, NRP could organize a mutual water company to provide water service to the Project. A mutual water company is not regulated by either LAFCO or the CPUC, but is a private corporation formed for the purpose of providing water to its shareholders at cost.43 Approximately 11 mutual water companies currently operate in Napa County.44 Under a mutual water company arrangement, the owners or lessees of each residential or business unit of the Project would hold a share in the company, which would entitle them to receive water and control the company’s management through shareholder voting. If NRP were to form and rely upon a mutual water company to provide water service to the Project, it would need to prepare a detailed engineering plan, a prospectus related to the offering of company shares and a filing with the California Department of Real Estate.45 A newly-formed mutual water company would likely enter into an operations and maintenance contract with an established, professional water utility service company to handle its day-to-day operations.
Third, NRP, with assistance from the County of Napa, could form a special public district to provide water service to the Project. There are multiple types of special districts that could be formed for this purpose, including a county water district, California water district, municipal water district, county service area, community services district, municipal utilities district or public utilities district.46 Formation of these districts would follow the process set forth in the Cortese-Knox-Hertzberg Local Government Reorganization Act of 2000, including submission of an application to LAFCO, a public hearing, consideration of a list of criteria by LAFCO and a vote of the affected landowners.47 Upon formation, a special district would be empowered to take all actions necessary to provide water service to the Project, including management of the water resources described in this WSA.
Fourth, CON could agree to provide water service to the Project. A charter city may provide water service outside of its boundaries,48 and in fact CON already does so in several locations. As noted above, CON currently provides water to the Project site for industrial purposes and already owns and operates water mains adjacent and up to the Project boundary. It has not yet been determined, however, whether CON will provide water service to the Project. Nonetheless, per CON’s request, Section 7 of this WSA evaluates the feasibility of CON serving the Project. If CON were to become the water purveyor, the local groundwater and recycled water resources
43 See CAL. PUB. UTIL. CODE § 2705. 44 See County of Napa, Napa County General Plan Update Draft Environmental Impact Report, at 4.13-35 (February 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&exturl=http://www.napacountygeneralplan.- com/], finalized in County of Napa, Napa County General Plan Final Environmental Impact Report, State Clearinghouse No. 2005102088 (December 20, 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&- exturl=http://www.napacountygeneralplan.com/]. 45 See CAL. CORP. CODE § 14310. Under these regulations, the incorporator of a mutual water company must certify that it has contacted LAFCO and the CPUC to determine if the area is within an existing water service area (which the Project site is not) or would be best served by an existing water company or agency. Neither the CON nor AmCan would be deemed in the best position to serve the Project in the absence of their agreement to do so. 46 See CAL. WATER CODE §§ 30000-33901 (county water districts), §§ 34000-38501 (California water districts), §§ 71000-73001 (municipal water districts); CAL. GOVT. CODE §§ 25210.1-25211.33 (county service areas), §§ 61000-61800 (community services districts); CAL. PUB. UTIL. CODE §§ 11501-14403.5 (municipal utility districts), §§ 15501-18055 (public utility districts). 47 See CAL. GOVT. CODE §§ 56000-57500. 48 See Hansen v. City of San Buenaventura, 42 Cal.3d 1172, 1180-81 (1986), appeal dismissed, 484 U.S. 804, 108 S.Ct. 50, 98 L.Ed.2d 15 (1987); County of Inyo v. Public Utilities Commission, 26 Cal.3d 154, 157 (1980); City of South Pasadena v. Pasadena Land & Water Co., 152 Cal. 579, 590 (1908); Sawyer v. City of San Diego, 138 Cal.App.2d 652, 658 (1956); Durant v. City of Beverly Hills, 39 Cal.App.2d 133, 136-37 (1940). AUGUST 25, 2011 23
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discussed in this WSA could become part of CON’s broader water supply portfolio, which would mutually enhance the reliability of water supplies for the Project and other customers served by CON. In order for CON to provide retail water service to the Project, the approval of LAFCO might be required as an extension of service.49
Lastly, AmCan could provide retail water service to the Project. The Project site is not currently within the AmCan water service area, but that area extends to State Route 12/29, approximately one-quarter mile south of the Project site.50 In order to extend its retail service area to include the Project, AmCan would require the approval of LAFCO following the process set forth in the Cortese-Knox-Hertzberg Local Government Reorganization Act of 2000. If AmCan were to become the water purveyor, the water resources discussed in this WSA could become part of AmCan’s broader water supply portfolio, which would mutually enhance the reliability of water supplies for the Project and other customers served by AmCan.
There are advantages and disadvantages to each of the five options set forth above from water resource management, financial and political perspectives. While cities and special districts serve the majority of urban water customers in California, state law provides that water service may also be provided by an investor-owned utility or mutual water company. Each type of organization has its strengths and weaknesses from an administration perspective. An investor- owned utility is not governed by a locally-elected board like a special district, but is comprehensively regulated by the CPUC, a state agency with special expertise in utility management and oversight. Ratepayers may participate in the CPUC process, and many larger Class A and B investor-owned utilities have access to capital markets superior to that enjoyed by special districts, which can be captured by non-service related political interests and weakened financially as a result. A mutual water company is governed directly by its members, who are the residents and businesses that receive water service from the company. In comparison to a special district, internal governance is accomplished pursuant to the Corporations Code rather than the Government Code, and members have substantial rights that are similar to those afforded special district ratepayers. A mutual water company may assess its members to pay for capital improvements, although it does not have any tax powers. Mutuals typically operate on a tax-exempt basis, like public agencies.
A special district’s boundary and infrastructure would be regulated by LAFCO, which can but does not always result in efficient and orderly development of water utilities. A special district providing water utility service could be consolidated with other municipal services, which could lead positively to greater administrative efficiency or negatively to an organization that ignores intelligent water resource management in favor of other political interests. One potential advantage of a public agency, such as a city or special district, is that agencies have the ability to issue tax-exempt bonds, which can lead to lower costs of financing for capital improvements. Investor-owned utilities, however, frequently moot that advantage by achieving operational efficiencies and avoiding costly public employee benefit packages. Ultimately, the decision
49 See CAL. GOVT. CODE § 56133; Napa County Local Agency Formation Commission, General Policy Determinations, at § V.(B) (April 4, 2011) [http://www.napa.lafco.ca.gov/uploads/documents/GeneralPolicy- Determinations.pdf]. 50 See City of American Canyon, Urban Water Management Plan 2010, at Figure 2.1 (2011) (“AmCan 2010 UWMP”); City of American Canyon, 2005 Urban Water Management Plan, at Figure 3-2 (January 2006) (“AmCan 2005 UWMP”) [http://www.ci.american-canyon.ca.us/Modules/ShowDocument.aspx?documentid=438]. 24 AUGUST 25, 2011
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about which type of water purveyor to use for the Project will be determined by the Project applicant with review by the County, LAFCO, the CPUC and California Department of Real Estate. A decision regarding the type of water purveyor to be used for the Project is not necessary at the water supply assessment phase of development.
As described above, there are five viable alternatives for the type of retail water purveyor that will provide water service to the Project. All five types are currently being considered by NRP. Importantly, the type of water purveyor used will not have any significant impact on the availability of the water resources described in this WSA. Each type of water purveyor would be equally able to rely upon local groundwater, imported surface water and recycled water, and those same supplies would be utilized no matter what type of purveyor is ultimately selected. Thus, this WSA refers simply to the “water purveyor” without identifying the exact nature of that entity.
If neither CON nor AmCan serves as the retail water purveyor, the Project will need to obtain water wholesale or conveyance service from one or both of those cities in order to import surface water from Barker Slough to the Project site, as discussed in Section 5.5 of this WSA. Such water wholesale or conveyance service does not require that the Project site be located within their respective city limits, spheres of influence or water service areas, but would be provided based on a contract between the retail water provider and one or both of the cities. This would be the case if the retail water purveyor were an investor-owned utility, a mutual water company or a special district.
2.4 Legal Requirements
SB 610 established the primary legal standards for assessing the sufficiency of water supplies for new development projects.51 Affected land developments are those that meet certain size thresholds. Those thresholds are met for developments that include more than 500 residential dwelling units, or industrial, manufacturing or processing plants, or an industrial park planned to house more than 1,000 persons, occupying more than 40 acres of land, or having more than 650,000 square feet of floor area.52 The Project, as described above, would include approximately 2,580 attached residential dwelling units in multi-story buildings, 15,000 square feet of restaurant space, 25,000 square feet of retail space, 50,000 square feet of office space, 140,000 square feet of industrial, research and development or warehousing space, and a 150- room condominium hotel, thus exceeding the size threshold for preparation of a water supply assessment.
These statutes require that as part of the environmental review conducted for a qualifying project pursuant to CEQA, the relevant public water supplier must prepare a “water supply assessment” of the reliability of water supplies for the project, considering normal, single dry and multiple dry years over a 20-year horizon. If no public water supplier is identified, as for the Project, then the water supply assessment is prepared by the local land use agency. The city, county or other land use agency considering land use approval must then analyze the environmental impacts of providing water to the project based upon the public water supplier’s analysis and any other relevant considerations.
51 See CAL. WATER CODE §§ 10910-10914. 52 CAL. WATER CODE § 10912(a). AUGUST 25, 2011 25
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The basic requirement is that a water supply assessment must “include a discussion with regard to whether the public water system’s total projected water supplies available during normal, single dry, and multiple dry water years during a 20-year projection will meet the projected water demand associated with the proposed project, in addition to the public water system’s existing and planned future uses, including agricultural and manufacturing uses.”53 An assessment must identify the water supply entitlements, water rights or water service contracts related to the planned water supplies for the project, as demonstrated by written contracts, capital financing plans, federal, state and local permits for construction of infrastructure and regulatory approvals required to be able to convey or deliver the water supplies.54 If the water demand for a proposed project is accounted for in an adopted urban water management plan (“UWMP”), the water supply assessment preparer may incorporate the plan information into the assessment.55 If there is no current UWMP or the current UWMP does not account for the Project’s projected water demand, such as is the case here where the Project was not accounted for in either CON’s or AmCan’s most recent UWMP adopted in 2011, the water supply assessment must be based on the available evidentiary record.56
If a project’s water supply includes groundwater, the water supply assessment must include the following information:
(1) A review of any information contained in the urban water management plan relevant to the identified water supply for the proposed project.
(2) A description of any groundwater basin or basins from which the proposed project will be supplied. For those basins for which a court or the board has adjudicated the rights to pump groundwater, a copy of the order or decree adopted by the court or the board and a description of the amount of groundwater the public water system, or the city or county if either is required to comply with this part pursuant to subdivision (b), has the legal right to pump under the order or decree. For basins that have not been adjudicated, information as to whether the department has identified the basin or basins as overdrafted or has projected that the basin will become overdrafted if present management conditions continue, in the most current bulletin of the department that characterizes the condition of the groundwater basin, and a detailed description by the public water system, or the city or county if either is required to comply with this part pursuant to subdivision (b), of the efforts being undertaken in the basin or basins to eliminate the long-term overdraft condition.
53 CAL. WATER CODE § 10910(c)(3). 54 See CAL. WATER CODE § 10910(d)(2). 55 See CAL. WATER CODE § 10910(c)(2). See also CAL. WATER CODE §§ 10610 et seq. (Urban Water Management Planning Act). 56 See CAL. WATER CODE § 10910(c)(3). 26 AUGUST 25, 2011
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(3) A detailed description and analysis of the amount and location of groundwater pumped by the public water system, or the city or county if either is required to comply with this part pursuant to subdivision (b), for the past five years from any groundwater basin from which the proposed project will be supplied. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records.
(4) A detailed description and analysis of the amount and location of groundwater that is projected to be pumped by the public water system, or the city or county if either is required to comply with this part pursuant to subdivision (b), from any basin from which the proposed project will be supplied. The description and analysis shall be based on information that is reasonably available, including, but not limited to, historic use records.
(5) An analysis of the sufficiency of the groundwater from the basin or basins from which the proposed project will be supplied to meet the projected water demand associated with the proposed project.57
When a water supply assessment relies upon unadjudicated groundwater, requirement (5) above does not prescribe a particular method for determining the boundaries of the groundwater basin or for assessing groundwater sufficiency, and the preparer and its experts possess substantial professional discretion to select methodologies that are appropriate for the proposed groundwater supply and project.58 As stated by the court that addressed this issue most recently,
Section 10910(f)(5) does not prescribe a particular analytical method for assessing groundwater sufficiency. The statute thus affords substantial discretion to the water supplier and its experts to select a methodology appropriate for assessing groundwater sufficiency for a proposed project. Furthermore, in our role as a reviewing court, we may not engage in a comparative analysis of methodologies employed by different experts. In technical matters requiring the assistance of experts and the use and interpretation of scientific data, we give substantial discretion to administrative agencies. Our task is limited to determining whether the agency action is arbitrary, capricious, or entirely lacking in evidentiary support.59
Thus, although a water supply assessment must include discussion of the most recent assessment of groundwater conditions by DWR, the preparer is not required to use the same boundaries or analytical methodology as DWR has used, as long as the substituted boundaries and
57 CAL. WATER CODE § 10910(f). 58 O.W.L. Foundation v. City of Rohnert Park, 168 Cal.App.4th 568, 593-94 (2008). 59 Id. at 592-93. AUGUST 25, 2011 27
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methodology are formed according to professional judgment based on evidence. The preparer may rely on technical and practical determinations about the appropriate groundwater boundaries and analytical methodologies, but those determinations are subject to review to the extent they are arbitrary, capricious or lacking in evidentiary support.60
Upon adoption, the water supply assessment is incorporated into the CEQA document being prepared for the project, and the lead agency must determine, based on the entire record, whether projected water supplies will be sufficient to satisfy demands for the project, in addition to existing and future uses.61
There are several general principles for analyzing the sufficiency of water supplies for new development.62 First, an environmental review document cannot simply ignore or assume a solution to any water supply constraint or limitation. Second, a review document for a large project to be built over a period of years cannot limit its analysis to water supplies needed for the first stage or first few years, but must assume the entire project will be built and analyze the impacts of supplying water to the entire project. Third, future water supplies must bear a likelihood of actually proving available; speculative sources and unrealistic allocations are generally insufficient. An environmental review document must include a reasoned analysis of the circumstances affecting the likelihood of availability for each water supply source. Finally, CEQA requires some analysis of the environmental impacts of possible alternative supplies that may be needed to supplement any uncertainty that may exist. Nonetheless, an analysis of alternative supplies is not necessary if it is clear that future water supplies will likely be available.63
For an assessment to be adequate when based on water supplies that are not yet available to the public water system, these future supplies need not be definitely assured through signed, enforceable agreements and already built or approved treatment and delivery infrastructure. Rather, it is expected that land use and water supply planning will occur through roughly contemporaneous processes for those future supplies. An assessment reflects sufficient certainty if it demonstrates a reasonable likelihood that such contracts, financing programs and regulatory approvals will be obtained in future.64
60 Id. at 594. 61 CAL. WATER CODE § 10911(b)-(c). 62 Vineyard Area Citizens for Responsible Growth, Inc. v. City of Rancho Cordova, 40 Cal.4th 412, 430-32 (2007). 63 See Santa Clarita Organization for Planning the Environment v. County of Los Angeles, 157 Cal.App.4th 149, 162-63 (2007) (holding that “some legal uncertainty”, caused by pendency of litigation related to the water supply, did not trigger the requirement of analyzing possible alternative supplies under the fourth principle, since the degree of uncertainty was insubstantial). 64 See Vineyard, 40 Cal.4th at 432-34. 28 AUGUST 25, 2011
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SECTION 3 WATER DEMANDS
As analyzed in this WSA, the Project consists of an approximately 154-acre redevelopment located within the County of Napa and adjacent to the southern limits of the CON. The Project will convert development on the site from historical heavy industries to approximately 2,580 residential units, commercial and retail space and a hotel. The potable and non-potable water uses expected for the Project are detailed in Table 4 and Table 5, respectively. The potable water use expected for the Project is approximately 620 AFY, including unaccounted-for water, which is the difference between the quantity of water supplied to a water purveyor’s system and the metered quantity of water used by the customers and includes water lost through leaky pipes, illegal service connections, meter inaccuracies and water used for fighting fires, among other losses. The non-potable water use expected for the Project is approximately 141 AFY, including unaccounted-for water.
3.1 Historical and Current Water Demands
Development of the Project site began as early as 1919-1920, when four groundwater wells were drilled on the site. By 1933, up to 13 wells had been drilled on the Project site and were used to extract groundwater for delivery to the cities of Crockett, Vallejo and Benicia, as well as the C&H (California & Hawaii) Sugar Refining Company facility located in Crockett.65 There are no groundwater extraction records available from this time period, but it can reasonably be assumed that the use of groundwater from the site was substantial, given the number of wells and the beneficial uses to which that water was placed.
Beginning in 1939, the Basalt Rock Company used the Project site as the location of a shipbuilding facility, which was active through the end of World War II. As with the earlier period of development, no water records exist from this time, although water use can be assumed to have been substantial given the industrial activity on the site and the domestic water demands of up to 3,000 workers, a portion of whom lived at the adjacent Shipyard Acres Community.66
Following World War II, the Project site was used by the Napa Pipe Company, Kaiser Steel and Oregon Steel Mills as the location for manufacturing of steel pipe and other heavy steel products. Water use records from the end of World War II through 1989 are rare, but in 1949-1950, USGS estimated that water demands on the Project site were approximately 1,230 AFY.67
During the gradually declining industrial use of the Project site between 1989 and 2004, when the Napa Pipe facility finally closed, pumping records from wells located on the Project site indicate that an average of 150 AFY were used for heavy industrial and office purposes.68 In addition, the site was connected to the potable water distribution system of CON during the period from 1955 to the present, and an unknown, additional quantity of water was used based on CON deliveries. Currently, relatively small amounts of water are used on the Project site for industrial, land maintenance, testing and office purposes. If the Project were not to be developed, industrial use of an undetermined quantity of water might resume on the site.
65 Stetson Report, at 1-4 [Exhibit C]. 66 Id. 67 Id. 68 Id. at 2-7 to 2-8. AUGUST 25, 2011 29
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3.2 Demands in Normal, Single Dry and Multiple Dry Water Years
In order to evaluate water supply reliability, California statutes require the consideration of water supplies and demands in normal, single dry and multiple dry water years. There is no statute or regulation that dictates the proper method for calculating demands in single dry and multiple dry water years, and no consistent approach has been developed by water resource professionals within the state.69
For purposes of this WSA, the water demands in single dry and multiple dry water years are estimated to equal the demands in normal water years. This approach is the same as that used by AmCan. It is more conservative than findings by CON that water demands within its service area immediately adjacent to the Project site declined by 31 percent during single dry and multiple dry water years compared to normal water years. CON has concluded that water demands declined based upon public notification of drought conditions and voluntary actions taken under its Water Shortage Contingency Plan.70 This WSA does not include any reduction in water demands for single dry or multiple dry water years when compared to normal water years because of the greater water conservation measures included in initial construction of the Project compared to generally older construction within CON, and a desire to be conservative in the WSA’s overall approach to water supply reliability planning.
3.3 Water Quality
A feature of the Project that affects water demands is that the Project will utilize two different sources of water based on the differing water quality requirements of Project demands. Specifically, indoor water uses for residential and commercial spaces, such as water for drinking, cooking and sanitation, require water treated to potable standards, while irrigation of exterior spaces may utilize high quality recycled water that does not meet potable standards. California state law encourages the use of recycled water whenever it is available and of adequate quality and reasonable cost, in order to conserve and optimize use of the state’s valuable water resources.71 The Project will seek to promote that important policy by using recycled water to meet the demands of landscape irrigation.72
3.4 Projected Water Demands
Projected water demands for the Project are shown in Table 4. The average daily demands for potable water are 549,700 gpd, which equals 620 AFY and an average pumping rate of 385 gallons per minute (“gpm”). This number includes water for indoor residential, commercial and community facility uses, a relatively small amount of water for irrigation of rear yards and a community garden, and 10 percent for unaccounted-for water. The maximum (peak) day demand is projected to be approximately 723,500 gallons, based on a multiplier of 1.3 times average day demands for indoor water uses (equaling 702,000 gallons)73 and the maximum day demands for irrigation of rear yards and a community garden as identified by HSE for the month
69 See, e.g., DWR, California Water Plan, Bulletin 160-05, Vol. III, at 3-7 (Update 2005) (“Each district has different assumptions and policies that guide their planning”). 70 See CON UWMP, at 9-1, 9-2 [Exhibit B]. 71 See CAL. WATER CODE §§ 13550 et seq. 72 HSE Report, § 2.4.1 [Exhibit A]. 73 Id. at §§ 2.1, 3.1, Table 3-1 n.3. 30 AUGUST 25, 2011
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of July (equaling 21,500 gallons).74 Those demands will need to be met with potable water and cannot be satisfied by the use of recycled water.
The average daily demand is used to evaluate the adequacy of existing and future water supplies, which is the purpose of this WSA. The maximum day demand and the peak hourly demand factors (multiples of the average daily demand) are used to size the related Project water and wastewater infrastructure, including the groundwater wells and pump stations, water treatment plant, wastewater treatment plant, water storage tanks and the water and sewer piping. The maximum day demand and peak hourly demand factors and engineering information pertaining to the Project water and wastewater infrastructure are provided in the HSE Report.75
Table 4. Projected Potable Water Demands for the Napa Pipe Project Water Use Water Use Water Use Land Use Quantity Factor (gpd)† (AFY)† Residential Multi-Story Residential 2,580 units 165 gpu 425,700 477 Senior Housing Units* 150 units 113 gpu 16,900 19 Commercial Restaurant 15,000 ft2 0.1 gpd/ft2 1,500 2 Retail 25,000 ft2 0.1 gpd/ft2 2,500 3 Offices 50,000 ft2 0.1 gpd/ft2 5,000 6 R&D/Light Industrial 140,000 ft2 0.1 gpd/ft2 14,000 16 Hotel 150 rooms 150 gpd/room 22,500 25 Community Facilities 15,600 ft2 0.1 gpd/ft2 1,600 2 Community Pool 1 unit 1,200 gpu 1,200 1 Irrigated Areas Rear Yards 2.3 acres 3,125 gpd/acre 7,200 8 Community Gardens 0.5 acres 3,125 gpd/acre 1,600 2 Total Potable Water Demands 499,700 560 Total Potable Water Demands with Unaccounted-For Water 549,700 620 Source: HSE Report, at § 2.1 [Exhibit A]. † All gpd figures are rounded to the nearest 100 gpd. All AFY figures are rounded to the nearest AF, except the totals, which are rounded to the nearest 10 AF. * The water use factor for senior housing units is based on adjusting the multi-story residential water use factor by the relative numbers of persons expected per dwelling, which is 1.5/2.2.
74 Id. at § 4.1.1. 75 Id. AUGUST 25, 2011 31
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The average annual demands for water to be used for landscape irrigation as shown in Table 5 are approximately 141 AFY. This number includes 10 percent for unaccounted-for water. The maximum day demand is projected to be approximately 259,000 gallons, based on irrigation requirements in July. Detailed information on the projected seasonal irrigation demand relative to the availability of recycled water was analyzed by HSE.76 Those water demands can and will be met with recycled water, as described in Section 6 of this WSA.
Table 5. Projected Non-Potable Water Demands for the Napa Pipe Project Water Use Water Use Land Use Quantity Factor (AFY)† Irrigated Areas Native Landscaping 12.8 acres 2.1 AFY/acre 27 Parks and Turf Areas 28.8 acres 3.5 AFY/acre 101 Total Non-Potable Water Demands 128 Total Non-Potable Water Demands with Unaccounted-For Water 141 † All numbers rounded to the nearest AFY.
3.5 Water Efficiency Strategies
There are many water efficiency strategies that can be implemented to reduce potable water demands for the Project. The CALFED Water Use Efficiency Program Plan identifies the potential for water efficiency practices to reduce per capita water demand to approximately 52 gpcd statewide, which is approximately 31 percent lower than the highly conservative estimate of 75 gpcd water demand used for planning purposes in this WSA.77 Specific methods to improve efficient water use identified in the CALFED study include the following:
• Installing ultra-low flush toilets that flush with 1.6 gallons per flush; • Using showerheads that use no more than 2.5 gpm when wide open; • Using faucets that flow at 2.2 gpm maximum, and are sensor activated in public restrooms; • Replacing more common and less efficient clothes washers with high efficiency tumbler- type clothes washers; and • Practicing routine common sense leak detection and control.78
It is intended that the Project will meet or exceed all of these CALFED water efficiency practice goals and comply at a minimum with the California Plumbing Code and the best management practices contained in the CUWCC’s Memorandum of Understanding.79 Additionally, the use of recycled water for all common area irrigation eliminates the use of potable water for this purpose. Thus, potable water will be used primarily indoors, with outdoor usage only for
76 HSE Report, at 25 [Exhibit A]. 77 This WSA uses a water demand factor of 165 gpd per unit, with 2.2 persons expected per unit. 78 HSE Report, at § 2.3 [Exhibit A]. 79 See California Urban Water Conservation Council Website [http://www.cuwcc.org]. 32 AUGUST 25, 2011
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irrigation of private backyards, which constitute a relatively small area of approximately 2.3 acres compared to 41.6 acres of recycled water irrigation.
In addition to these permanent water conservation strategies, water purveyors typically adopt water shortage contingency plans that reduce water usage during temporary periods of supply restrictions. The amount of targeted reduction depends on the volatility of the water supplies relied upon by the water purveyor. Since this WSA analyzes the use of highly reliable local groundwater, imported surface water and recycled water to meet all Project demands, which are not subject to high volatility when used conjunctively as a portfolio, it is expected that the water purveyor for the Project will be able to adopt relatively light-handed water reduction strategies. In furtherance of the need to conserve water on a statewide basis, the water purveyor will adopt a water shortage contingency plan consistent with the types of plans adopted by other similarly situated water purveyors. An example of such a plan is that adopted by CON, as described in Sections 7.2.6.2 and 7.2.6.3 of this WSA.
3.6 Phasing of Projected Water Demands
While the water demands for the Project will all occur within the 20-year timeframe analyzed in this WSA, they will not arise at a single point in time. The Project is expected to be developed in three phases, so that water demands associated with the Project would start in 2010 and reach their full levels at expected buildout in 2020. Phase 1, which includes site remediation and fill, will be constructed in 2011 to 2014, and this WSA assumes that all Phase 1 water demands will commence at the beginning of that five-year planning period in 2010. Phase 2 will be constructed in 2015 to 2017, with this WSA assuming that Phase 2 water demands will commence in 2015. Phase 3 will be constructed in 2018 to 2020, and since water supply planning is estimated at five-year intervals, this WSA assumes that Phase 3 water demands will also commence in 2015. Table 6 and Table 7 show the non-potable and potable water demands of each Project phase, respectively.
Table 6. Projected Non-Potable Water Use by Phase for the Napa Pipe Project
Water Yearly Demand Phase (Acres) Use by Phase (AFY) † Land Use (units) 1 2 3 Factor 1 2 3 Native Landscaping 3.5 3.3 6.0 2.1 7 7 13 Parks and Turf Areas 11.1 14.5 3.2 3.5 39 51 11 Total Non-Potable Water Demands 46 58 24 Total Non-Potable Water Demands with Unaccounted-For Water 51 64 26 Cumulative Non-Potable Water Demands with Unaccounted-For Water 51 115 141 † Water use factors are the same as in Table 5, converted to AFY/acre.
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Table 7. Projected Potable Water Use by Phase for the Napa Pipe Project
Water Average Daily Demand Yearly Demand Phase Use by Phase (gpd) by Phase (AFY) † Land Use (units) 1 2 3 Factor 1 2 3 1 2 3 Residential Multi-Story Residential (units) 857 866 857 165.0 141,400 142,900 141,400 158 160 158 Senior Housing (units) 150 0 0 113.0 16,900 0 0 19 0 0 Commercial Restaurant (ft2) 15,000 0 00.1 1,500 0 02 00 Retail (ft2) 0 25,000 0 0.1 0 2,500 0 0 3 0 Offices (ft2) 20,000 20,000 10,000 0.1 2,000 2,000 1,000 2 2 1 R&D/Light Industrial (ft2) 0 20,000 120,000 0.1 0 2,000 12,000 0 2 14 Hotel (ft2) 150 0 0 150.0 22,500 0 0 25 0 0 Community Facilities (ft2) 10,500 3,600 1,500 0.1 1,100 400 200 1 1 1 Community Pool (units) 1 0 0 1,200.0 1,200 0 0 1 0 0 Irrigated Areas Rear Yards (acres) 1.0 0.7 0.6 3,125.0 3,100 2,200 1,900 4 3 2 Community Gardens (acres) 0.0 0.5 0.0 3,125.0 0 1,600 0 0 2 0 Total Potable Water Demands 189,700 153,600 156,500 210 175 175 Total Potable Water Demands with Unaccounted-For Water 208,600 169,000 172,100 235 190 195 Cumulative Potable Water Demands with Unaccounted-For Water 208,600 377,700 549,700 235 425 620 † Water use factors are the same as in Table 4. All numbers rounded to the nearest 100 gpd or nearest AFY, except the totals, which are rounded to the nearest 5 AF.
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SECTION 4 LOCAL GROUNDWATER SUPPLIES
One source of potable water for the Project will be groundwater underlying the Project site. The property overlies the Sonoma Volcanics aquifer of the Napa Valley Subbasin, which serves as a natural underground reservoir for local water supplies. This section of the WSA analyzes the physical availability of groundwater for the Project from that aquifer, as well as the legal and institutional mechanisms that control use of the resource.
Based on the analysis contained in this WSA, the Project will develop up to approximately 620 AFY of groundwater for the Project, which satisfies all Project demands. The Project will have sufficient water rights to groundwater based on correlative overlying rights associated with the Project site. The groundwater investigation was conducted by Stetson; peer review was provided by Luhdorff & Scalmanini Consulting Engineers. The investigation concluded that the target aquifer system, i.e., the Sonoma Volcanics, can reliably produce at least 3,100 AFY on a long- term basis, which is sufficient to meet the needs of the Project as well as other identified groundwater users in the surrounding Suscol area. Use of groundwater for the Project is not expected to injure other nearby groundwater users such as those in the MST area.
4.1 Basin Description and Applicable Technical Studies
This section briefly describes the groundwater basin underlying the Project site and adjacent groundwater basins, and introduces technical studies applicable to the Project. Napa County groundwater resources have been evaluated in various technical studies. However, study areas, sub-regions and terminology regarding groundwater basins have not been consistent. This confounds the direct comparison of some analyses, findings and conclusions between studies. For purposes of this WSA, the DWR basin terminology is used. Other terminology is used only for illustrative purposes, as needed.
4.1.1 California Department of Water Resources
DWR’s Bulletin 118 series provides comprehensive descriptions of groundwater basins, some of which are subdivided into smaller subbasins. According to the most recent document, Bulletin 118—Update 2003, the Project site is located in the southern tip of the Napa Valley Subbasin, as shown in Figure 3. The Napa Valley Subbasin occupies the essentially flat floor of the Napa Valley from just north of Calistoga to the Project site in the south. The Napa Valley Subbasin, the Sonoma Valley Subbasin and the Napa-Sonoma Lowlands Subbasin together constitute the Napa-Sonoma Valley Groundwater Basin. The Napa-Sonoma Lowlands Subbasin extends south and west of the Napa Valley Subbasin. The Napa River traverses the Napa-Sonoma Lowlands Subbasin from approximately the Highway 29 causeway (just south of the Project site) to its estuary where it discharges into San Pablo Bay. The Sonoma Valley Subbasin is located entirely in Sonoma County, it does not share a boundary with the Napa Valley Subbasin, and it is of little importance to this WSA.
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FIGURE 3 Study Areas Napa Pipe Site MST (Farrar & Metzger, 2003) Napa Valley Subbasin of Napa - Sonoma Valley Groundwater Basin Conceptual Groundwater Flow Direction MST Area, October 2001 Groundwater Flow Direction (Farrar & Metzger, 2003) Groundwater Elevation Contour, Dashed Where Inferred (Feet, MSL)
Yountville
?
N a p a R i v e r
HOWELL MOUNTAINS
MAYCAMAS MOUNTAINS
29
Downtown Napa
12
SUSCOL AND MST STUDY AREAS IN RELATION TO NAPA VALLEY SUBBASIN
SOURCE: Study area, drainage basin and groundwater contours 012 for MST area are from USGS (Farrar and Metzger, 2003 Water-Resources Investigations Report 03-4229. Miles J:\jn2222\SiteLocationMap_wMST_v2.0.mxd Z.10/07/2009 Stanley J:\jn2222\SiteLocationMap_wMST_v2.0.mxd WATER SUPPLY ASSESSMENT FOR THE NAPA PIPE PROJECT
In the most recent 2003 update of Bulletin 118, DWR did not complete an assessment of either the Napa-Sonoma Valley Groundwater Basin or the Napa Valley Subbasin.80 In the prior update of Bulletin 118 in 1980, DWR found that the Napa-Sonoma Valley Basin and two of its subbasins, including the Napa Valley Subbasin, showed no evidence of overdraft and were not classified as “basins with special problems.”81 This represented no change from the original Bulletin 118 from 1975, in which DWR also did not find overdraft conditions to exist.82
DWR has not conducted any other recent technical studies of groundwater resources in the Project vicinity.
4.1.2 United States Geological Survey
The United States Geological Survey (“USGS”) has conducted several studies of groundwater conditions in the Suscol and neighboring areas. Kunkel and Upson (1960) provided an assessment of the geology and the occurrence, source and movement of groundwater in the Napa and Sonoma Valleys. The report contained discussions of groundwater level trends, groundwater storage estimates and estimates of historical pumpage. It further included information and discussions specific to the Suscol area, i.e, the area where the Project site is located. This report was substantially relied upon in the preparation of the groundwater assessment for this WSA.83
Johnson (1977) provided an assessment of groundwater resources in the lower MST area. The report provided detailed discussions of the occurrence and movement of groundwater, estimated groundwater recharge and discharge (including pumpage), discussed groundwater level fluctuations and estimated groundwater storage and changes in storage.84
Farrar and Metzger (2003) provided the USGS’s most recent hydrologic assessment of the MST area to evaluate possible strategies for reducing apparent groundwater level declines. The emphasis of this study was on documenting changes in groundwater levels within the study area and identifying the principal causes of the groundwater level declines.85 The MST area is largely outside of the Napa Valley Subbasin. However, due to its proximity to the Project site, and recognizing increased demands on groundwater resources in portions of the MST area and significant groundwater level declines, the MST area studies are also pertinent to the Project.
80 California Department of Water Resources, California’s Groundwater, Bulletin No. 118–2003 Update (2003) (“Bulletin 118”) [http://www.water.ca.gov/groundwater/bulletin118/bulletin118update2003.cfm]. 81 California Department of Water Resources, California’s Groundwater, Bulletin No. 118–1980, at 3, 19, 21 (1980) [http://www.water.ca.gov/pubs/groundwater/bulletin_118/ground_water_basins_in_california__bulletin_118-80_/- b118_80_ground_water_ocr.pdf]. 82 Id. at 20. See also California Department of Water Resources, California’s Ground Water, Bulletin No. 118-75 (1975). 83 F. Kunkel and J.E. Upson, Geology and Groundwater in Napa and Sonoma Valleys, Napa and Sonoma Counties, California, Geological Survey Water Supply Paper 1495 (1960) [Exhibit F]. 84 M.J. Johnson, Ground-Water Hydrology of the Lower Milliken-Sarco-Tulucay Creeks Area, Napa County, California, United States Geological Survey Water Resources Investigation Report No. 77-82 (1977) [http://pubs.er.usgs.gov/usgspubs/wri/wri7782]. 85 C.D. Farrar and L.F. Metzger, Ground-Water Resources in the Lower Milliken-Sarco-Tulucay Creeks Area, Southeastern Napa County, California 2000-2002, United States Geological Survey Water-Resources Investigations Report 03-4229 (2003) (“MST Report”) [Exhibit G]
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4.1.3 Napa County
Chapter 16, Groundwater Hydrology, of the Napa County 2005 Baseline Data Report was developed with the explicit intention of applying hydrologic models and analyses toward future planning considerations. Chapter 16 sets forth a framework of state and local policies relating to groundwater use. The remainder of the chapter summarizes geologic and hydrogeologic information provided by others and describes the hydrologic models. For the largest portion of the Napa Valley, the report refers to conclusions that were formulated by others and were based on a data record ending in 1989. The development, calibration and application of the aforementioned hydrologic models are comprehensively described in the Final Technical Appendix. At the time of model development, hydrologic data in the Suscol area were scarce and the model was not calibrated in this portion of the model domain. Overall, the Napa County 2005 Baseline Data Report and the Final Technical Appendix are of limited use for the Project.86
The 2050 Napa Valley Water Resources Study was a collection of seven stand-alone technical memoranda (TM1 through TM7).87 The 2050 Study reviewed and analyzed previous pertinent planning assumptions (TM1), systematically analyzed the water demands and supplies throughout the County with projections to 2050 (incorporated and unincorporated areas) (TM2 through 5), compared these quantities (TM6) and described several local and regional water supply projects (TM7).
To facilitate the supply and demand analyses, the 2050 Study divided the study area into eight sub-regions; five of these sub-regions were combined to form what the authors refer to as the “Main Basin”. The Main Basin approximately occupies the floor of the Napa Valley from just north of Calistoga to the county line in the south. It excludes both the MST area and an area identified as the Carneros sub-region. As such, the Main Basin covers most of the Napa Valley Subbasin designated by DWR; however, it also includes a substantial portion of the Napa- Sonoma Lowlands Subbasin in the American Canyon area.
The 2050 Study is important because it included hydrographs showing the long-term trends for groundwater levels in the Napa Valley. Hydrographs from wells located near Calistoga (1975- 2002), St. Helena (1975-2002), Yountville (1975-2002) and Napa (1930-2002) showed steady long-term groundwater levels, despite significant increases in irrigated vineyard acreage in the county between 1975 and 2002.88 The 2050 Study concluded that groundwater pumpage had not exceeded long-term groundwater recharge as of 2002. Groundwater levels from wells south of Napa, in the Suscol area or farther south toward American Canyon, were not evaluated.
The 2050 Study also determined that the presently available water supplies in the unincorporated areas of the Main Basin (comprised of groundwater, surface water and recycled water) were sufficient to meet demands in both wet and normal hydrologic years. However, the supplies were found to fall short of demands during single-dry and multiple-dry hydrologic year conditions. This situation was predicted to intensify based on a 2020 and 2050 planning
86 See County of Napa, Napa County Baseline Data Report, “Groundwater Hydrology”, (November 2005) [http://www.napawatersheds.org/docs.php?oid=13358&ogid=10112]. 87 West Yost & Associates, 2050 Napa Valley Water Resources Study (October 2005) (“2050 Study”) [Exhibit D]. The 2050 Study consists of seven technical memoranda (“Tech. Memo”). 88 2050 Study, Tech. Memo No. 5, at 7-16. 38 AUGUST 25, 2011
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horizon.89 Over that period, increases in irrigation demands account for the bulk of increases in total water demands within the Main Basin.90 Demands for agricultural irrigation in the Main Basin in 2050 were calculated by assuming current demands, plus the conversion of all existing vineyards planted at 726 vines per acre and native vegetation existing on slopes of less than 30 percent to vineyards planted at 1,815 vines per acre, i.e., maximum planting throughout the entire Napa Valley.91 The actual 2050 water demands in the Main Basin will be dependent on water availability, climate, marketability of wine from Napa Valley and other factors.92
In addition, the following conclusion from the 2050 Study is of importance to the Project:
Even though there appears to be sufficient supplies in the southern portions of the Napa Valley, additional pumpage from the groundwater basin in this area (even seasonally), may allow saline groundwater to migrate and intrude into the higher quality groundwater supplies further northward in the Napa Valley.93
4.1.4 City of Napa
In 2005, WYA provided a feasibility study to CON regarding the possibility of using groundwater from the Napa Pipe Project site as a new water supply for CON.94 The study evaluated use of Project site groundwater as a supplemental potable water source, as a non- potable water supply or as a dry-year or emergency water supply. Following its analysis in that study, WYA recommended “that [CON] continue to consider acquisition of the water/mineral rights associated with the [Project site]”, and suggested additional data collection and analyses that should be conducted “to help determine the maximum sustainable production capacity” of wells located on the site.95 Although WYA was also engaged in preparing the 2050 Study at the time of this analysis, WYA did not withhold recommending that CON consider groundwater development in light of the 2050 Study’s conclusions regarding potential future groundwater shortfalls.96 While CON did not take affirmative action to foreclose the possibility of gaining access to groundwater underlying the Project site, to date it has not acquired any groundwater or access rights in the property. Instead, the property was acquired by NRP for purposes of developing the Project.
The CON Planning Department staff also evaluated local groundwater supplies in 2007 in a negative declaration adopted under CEQA for a proposed groundwater well to be located adjacent to the Project site and used for purposes of a bottled water operation by Triton Naturals, LLC. CON staff determined in an initial study that the project, which proposed the extraction of approximately 140 AFY of groundwater from the Sonoma Volcanics, would not have a
89 Id. at 1, 6, 21-22; 2050 Study, Tech. Memo No. 6, at 10-11. 90 2050 Study, Tech. Memo No. 3, at 18. 91 Id. at 7, 15-17. 92 Id. at 21. 93 2050 Study, Tech. Memo No. 5, at 16. 94 West Yost & Associates, Technical Memorandum: Feasibility Level Evaluation of the Groundwater Supply Available from the Napa Pipe Corporation Facility for Use as a Municipal Supply, Project No. 424-02-05-03.01 (August 16, 2005) (“City Feasibility Study”) [Exhibit E]. 95 Id. at 16. 96 See Section 4.1.3.
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significant impact on groundwater resources.97 Ultimately, the CON City Council disapproved the project based on concerns about truck traffic, plastic bottle waste and exporting groundwater out of the area.98
4.1.5 Investigation for the Project
For purposes of this WSA, a hydrogeological investigation of groundwater resources underlying the Project site was conducted by Stetson, the report from which is attached as Exhibit C to this WSA.99
Relying on the Stetson Report, this WSA evaluates the availability and reliability of groundwater resources primarily in the southern Napa Valley Subbasin, referred to as the Suscol area. As noted above, according to DWR the Napa Valley Subbasin is not generally experiencing overdraft conditions. However, declining groundwater levels have been documented over several decades in portions of the MST area, which indicates that groundwater extractions exceed long-term groundwater recharge in that area. While the Project site is not located within the MST area, and the MST area only partially overlaps the Napa Valley Subbasin, this WSA evaluates potential hydraulic communication between the Sonoma Volcanics aquifer in the vicinity of the Project site and the water-bearing formations in the MST area, including the effect that groundwater extractions for the Project would have on groundwater availability in the MST area. In addition, this WSA evaluates the effects that groundwater extractions for the Project would have on the southern Napa Valley Subbasin in the Suscol area and on other currently existing and potential future groundwater users in the surrounding Suscol area.
The Stetson Report based its evaluation of groundwater underlying the Project site on a review of all previously published studies and data related to the Napa Valley Subbasin, the Suscol area and the MST area.100 In addition, Stetson performed three field investigations to gather additional information about the characteristics of the Sonoma Volcanics aquifer and groundwater underlying the Project site: a passive groundwater level monitoring program and water quality analysis performed in 2007;101 construction and testing of a new deep well (NRP-01) in 2008;102 and measuring of groundwater levels in 2009.103 Based on information contained in prior reports and the new field data, Stetson: (i) analyzed the connection between groundwater underlying the Project site and the Napa River; (ii) estimated the quantity of groundwater available in the Suscol area of the southern Napa Valley Subbasin on a sustainable long-term basis, and (iii) estimated the impacts of groundwater extractions for the Project on groundwater levels at several locations chosen to represent other groundwater users and the boundary of the MST area.
97 City of Napa Planning Department, Initial Study of Environmental Significance, at 7 (January 24, 2007), contained in Appendix C to Stetson Report [Exhibit C]. 98 See “Crystal Geyser loses bid to pump mineral water from Napa,” Napa Valley Register (September 7, 2007). 99 See generally Stetson Report [Exhibit C]. 100 Id. at 1-2, 1-3. Stetson Engineers also conducted analyses suggested by WYA in their 2005 feasibility study on behalf of the City. Id. at 1-3; City Feasibility Study, at 16 [Exhibit E]. 101 Stetson Report, at v, Appendix A [Exhibit C]. 102 Id. at v, vi, Appendix B. 103 Id. at v. 40 AUGUST 25, 2011
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4.2 Local Groundwater Conditions
4.2.1 Occurrence of Groundwater
Groundwater beneath the Project site exists in two distinct water-bearing aquifer systems: a shallow, unconfined alluvial aquifer and a deeper, confined volcanics aquifer.104 The top of an unconfined aquifer is the water table, which is the plane where groundwater pressures are equal to atmospheric pressure. The lower boundary of an unconfined aquifer is a layer of much less permeable material than the aquifer itself. For comparison, a confined aquifer is a layer of water-bearing permeable material that is sandwiched between two confining layers of much less permeable material. Confined aquifers are completely filled with groundwater, and they do not have a free water table. If the upper confining layer is penetrated by a well, groundwater will rise above the top of the aquifer. If the groundwater rises above the ground surface, the confined aquifer will yield a free-flowing well.
On the Project site, the shallow aquifer system is comprised of a thin veneer of younger alluvium underlain by older alluvium. These alluvial deposits consist of similar unconsolidated clay, silt, sand and gravel. The transition from younger alluvium to older alluvium is noted on the well log of only one of the on-site wells; this is probably due to the similar composition of these geologic units. Borehole lithologic data suggest that the alluvial deposits extend from the ground surface to depths ranging between 50 and 354 feet below ground surface (“bgs”) at the Project site, indicating substantial spatial variability. In addition, based on the lithologic data, a clay layer was identified within the alluvial deposits that ranges in thickness and depth from 15 feet at NRP-01 to 354 feet at the Suscol Well.
The alluvial deposits are underlain by a highly heterogeneous assemblage of tuff, pumice, tuff breccia, interbedded flows of andesite and basalt, rhyolotic flows, welded rhyolotic tuff, and massive diatomaceous clay known as the Sonoma Volcanics.105 The Sonoma Volcanics are also present at depth beneath the alluvial deposits throughout much of the Napa Valley. Based on available on-site borehole lithologic information, the transition from alluvial deposits to Sonoma Volcanics occurs at depths ranging from 50 to 354 feet bgs. As shown in Table 8, the deep wells on the Project site were drilled to depths ranging from 450 to 860 feet bgs; none of these wells fully penetrate the Sonoma Volcanics. Based on available data, the minimum thickness of the Sonoma Volcanics aquifer at the Project site ranges from 400 to 681 feet.
The deepest known well in the Suscol area—known by its state well number, 5/4-26B1—is located about one-half mile east of the Project site and was drilled to a depth of 1,440 feet bgs. The depth to the top of the Sonoma Volcanics in that well is 380 feet bgs, so that the thickness of the aquifer in that location is over 1,000 feet.
The predominant source of fresh water in the Sonoma Volcanics is infiltration of precipitation on the exposed tuff and pumice beds in the hills bordering the valley.106 Groundwater may also enter the Sonoma Volcanics from overlying alluvial materials on the valley floor, but this
104 Id. at 2-2, 2-3. 105 Id. at 2-2. 106 Id. at 2-10 to 2-11.
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Table 8. Lithology of Deep Wells on the Project Site
State Well Total Formations (feet bgs) ID Altitude Depth Younger Older Sonoma Name T5N/R4W- (feet msl) (feet) Alluvium Alluvium Volcanics NRP-01 26E2 8.55 766 n/a 0-120 120-766 Suscol 27H2 8.17 860 3-20 20-354 354-860 Syar 26E1 7.15 806 n/a 4-125 125-806 No. 3 27A1 9.65 795 n/a 10-130 130-795 Bio Cell 26N1 8.55 450 n/a 2-50 50-450 Source: Stetson Report, at 2-3, Table 2 [Exhibit C]. Note: “msl” = mean sea level; “bgs” = below ground surface.
recharge component is believed to be small based on the low permeability of the overlying materials. The majority of groundwater available at the Project site and its vicinity is derived from subsurface flow, i.e., groundwater flowing southward along the longitudinal valley axis from northern Napa Valley toward San Pablo Bay. A smaller amount is derived from recharge of rainfall in the Howell Mountains east of the Project site, in an area separate from the source area recharging the MST area.107 This inflow of groundwater from the north and east is demonstrated by the conceptual groundwater flow direction arrows in Figure 3 in this WSA and in Figures 7 and 11 to the Stetson Report. Once inflows from the north and east enter the Sonoma Volcanics aquifer in the Suscol area, they are commingled and form a single groundwater source from which the Project and other local groundwater users may draw.
On a regional scale, groundwater that reaches the Suscol area eventually flows south toward San Pablo Bay.108 There are no known groundwater users south of the Project site that would be impacted by groundwater extracted to serve the Project.
4.2.2 Historical and Existing Wells
There are currently five groundwater wells located on the Project site that penetrate the Sonoma Volcanics aquifer, as listed in Table 8.109 Well No. 3 was drilled in 1920 to a depth of 795 feet and is no longer used. The Bio Cell well was drilled in 1930 to a total depth of 450 feet and is also not used currently.110 The two wells that have been used in recent years to supply water for industrial uses on the Project site are the Suscol Well, which was drilled in 1923 to 860 feet, and the Syar Well, which was drilled in 1932 to a depth of 806 feet.111 In September 2008, Stetson oversaw the drilling to 766 feet of a test well on the Project site, labeled NRP-01. The deep wells listed in Table 8 are exclusively completed in the confined aquifer of the Sonoma Volcanics. Since this is the target aquifer for groundwater resources development for the Project, these wells are of particular interest in the context of this WSA. With the exception of
107 Id. at 2-5 to 2-6, 2-10 to 2-13. 108 Id. at 2-11. 109 Id. at 2-4. 110 Id. 111 Id. 42 AUGUST 25, 2011
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NRP-01, these wells are very old, i.e., between about 75 and 90 years, and damage to the casing in wells of this age is quite common. Such damage can provide preferential flow paths and facilitate groundwater exchange between the shallow alluvial aquifer and the deeper aquifer in the Sonoma Volcanics. To prevent this, the Project envisions proper destruction of these wells, other than NRP-01.112
In 1993, the consulting engineering firm Montgomery Watson conducted a 24-hour constant rate aquifer test of the Suscol Well. The well was pumped at an average rate of 672 gpm, resulting in a specific capacity of 22.4 gpm/ft of drawdown.113
In addition to the deep production wells penetrating the Sonoma Volcanics, there are numerous (over 70) shallow observation and extraction wells located on the Project site.114 These wells are involved in extensive site cleanup operations and corrective action monitoring. Since these wells are exclusively completed in the unconfined alluvial aquifer, they are of limited relevance to the objectives of this WSA and, consequently, they are not discussed in detail in this WSA.
4.2.3 Historical Pumping and Water Levels
Owners of the Napa Pipe property have extracted groundwater from the Sonoma Volcanics aquifer beneath the site for many years. For example, in the early 1900s, a well-field was developed on the property for extraction of groundwater that was then piped to Vallejo, Crockett and Benicia, California for beneficial uses.115 As shown in Table 9, at least 14 wells were drilled in the Suscol area by 1933, of which 13 were located on or immediately adjacent to the Project site (all except Smith Brown No. 1). Limited water level data from that period reported that wells drilled in the Sonoma Volcanics were free-flowing above the land surface, including McKee Nos. 1, 2 and 3, Stanley No. 1 and Smith Brown No. 1.116
Wells located on the Project site have consistently produced large quantities of groundwater. There are, however, sparse historical records regarding the amount of water produced from wells in the Suscol area and on the Project site. USGS estimated that in 1949-1950, when industrial activity was roughly representative of that by Napa Pipe during the period following World War II, groundwater production was approximately 1,230 AFY.117 This is roughly double the projected groundwater demands of the Project. Groundwater withdrawal in the Suscol area was substantially reduced between 1949-50 and 1951-52.
112 See HSE Report, at §§ 2.4.1, 5.1 [Exhibit A]. The one exception is the Syar Well, which is owned by Syar Industries and will not be destroyed without that company’s agreement. 113 Montgomery Watson, Suscol Production Well and Deep Aquifer Characterization Report, Napa Pipe Corporation, Napa, California (October 1993) (“MW Report”) [Exhibit H], summarized in Stetson Report, at 3-1 [Exhibit C]. 114 Id. at 1-3. 115 Id. at 1-4, 2-6. 116 Id. 117 Id. at 1-4, 6-1.
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Table 9. Groundwater Production Wells Drilled in the Suscol Area State Well ID Well Names Depth Date Drilled Active? 27K1 McKee No. 1 276 1919 No 27K2 McKee No. 2 456 1919 No 27A1 McKee No. 3; Well No. 3 795 1920 No 27Q1 Stanley No. 1 600 1920 No 27H1 McKee No. 4 1,226 1923 Unknown 27H2 Suscol 860 1923 Yes 26N1 C&H No. 1; Bio Cell 450 1930 No 27R2 Stanley No. 2 331 1930 No 26M1 C&H No. 6 939 1931 No 26M2 C&H No. 2 682 1931 No 27R1 Stanley No. 3 485 1931 Unknown 23C2 Smith Brown No. 1 323 Before 1932 Unknown 26E1 C&H No. 7; Syar 806 1932 Yes 26B1 Unknown 1,440 1933 Unknown Unknown East Vineyards Unknown Unknown Yes Unknown SPP Vineyards Unknown Unknown Yes Unknown Syar Quarry Unknown Unknown Yes 26E2 NRP-01 766 2008 No Source: Stetson Report, at 1-5, 2-3, 4-5 [Exhibit C].
Although industrial use of the Project site and adjacent properties in the Suscol area continued from 1950 through the 1980s, no groundwater production or level data was discovered during the preparation of this WSA and the Stetson Report.118 During the period from 1989 through 2005, when industrial activity on the Project site had slowed considerably, groundwater production was measured and recorded as set forth in Table 10. During that recent 17-year period, groundwater production ranged from 67 to 228 AFY and averaged 146 AFY.119 The 146 AFY average excludes 2005, since available data only covers the period from January through May 2005. In any event, the 146 AFY figure is undoubtedly low, due to incomplete data in several other years as well. If the incomplete years are excluded, the average production was 150 AFY. For purposes of this WSA, recent historical groundwater use is estimated to have been at least 150 AFY.
118 See id. at 1-5. 119 Id. at 2-7, 2-8. 44 AUGUST 25, 2011
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Table 10. Groundwater Production at the Project Site (1989-2005) Year Pumping Year Pumping 1989 87 1998 204 1990 141 1999 226 1991 228 2000 104 1992 182 2001 176 1993 116 2002 *190 1994 152 2003 *109 1995 113 2004 67 1996 *127 2005 *45 1997 *119 Average 146 Source: Stetson Report, at 2-8, Table 5 [Exhibit C]. * Incomplete data available for these years, thus the pumping figures are minimums.
Specific groundwater production data for other wells in the Suscol area in recent years is unavailable. Stetson estimated that groundwater production may have been approximately 714 AFY during at least the past seven years, based on the acreage of vineyards planted to the east of the Project site multiplied by the typical crop water requirement for vineyards in the area.120 In addition, Stetson estimated that approximately 50 AFY is used at the Syar Industries rock quarry located one mile northeast of the Project site.121 When combined with groundwater production of 150 AFY on the Project site, recent baseline groundwater production from the Sonoma Volcanics in the Suscol area is best estimated at approximately 910 AFY.
The USGS reported January 1950 groundwater levels in on-site and vicinity wells, which ranged from 2.17 to 72.72 feet bgs and from 1.10 feet above mean sea level (“msl”) to 60.79 below msl.122 A groundwater level contour map for the alluvial and volcanic aquifers in the Suscol area for December 1949 and January 1950, as created by USGS, is attached as Figure 8 to the Stetson Report and shows a generalized groundwater depression to 50 feet below msl in the vicinity of the Project site. While these groundwater levels were related to annual extraction volumes, they also reflected a seven-year period (1944-50) of distinctly below-average precipitation. Subsequent water level measurements in Sonoma Volcanics aquifer wells showed an almost 27- foot rise from December 1949 to March 1952. This water level recovery coincided with a substantial decrease in pumping in the Suscol area and also slightly above average annual precipitation.123
120 Id. 121 Id. at 4-5, 6-3. 122 Id. at 2-6, 2-7, Table 4. 123 Id. at 2-6, Figure 8.
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Recorded groundwater levels are not available for the 1989-2004 period, but during observations made by Stetson in 2007, 2008 and 2009, groundwater levels at all wells on the Project site were at or above the ground surface.124
Overall, historical groundwater extraction and level data demonstrate that the Sonoma Volcanics constitute a high-yielding confined aquifer in the Suscol area that has reliably satisfied groundwater demands even during times of prolonged below-average precipitation.
4.2.4 Recent Field Investigations
As part of its investigation, Stetson designed, implemented and reported on a passive monitoring program in 2007 and conducted a pumping test in 2008. Previously collected data was deemed incomplete and could not provide sufficient accuracy when evaluating the Sonoma Volcanics aquifer as a water supply source. The 2008 pumping test was designed specifically to address the data gaps, and the information provided by that test allowed Stetson to analyze the Sonoma Volcanics aquifer in the Suscol area with a reasonable degree of certainty.
4.2.4.1 2007 Monitoring Program
In 2007, Stetson designed and implemented a comprehensive monitoring program to assess groundwater conditions beneath the Project site.125 The program consisted of both groundwater level and groundwater quality data collection, and included the deployment of six data loggers in four existing wells, one new observation well and the Napa River to measure and record water levels and temperatures.126 Based on analysis of the collected data, Stetson formulated the following key findings and conclusions:
• Groundwater levels in the shallow alluvial aquifer system and the deeper Sonoma Volcanics aquifer system were distinctly different from each other, indicating a high degree of hydraulic separation between the aquifer systems.127
• The hydraulic head in the Sonoma Volcanics was consistently greater than in the alluvial aquifer system (and two of the deep wells [the Suscol and the Syar wells] were observed to be free-flowing) indicating both an upward hydraulic gradient and highly confined conditions in the Sonoma Volcanics.128
• Groundwater in the alluvial aquifer was high in dissolved mineral content (brackish) and similar to surface water in the Napa River. Groundwater from the Sonoma Volcanics was of very good quality and low in general mineral content. This also indicates hydraulic separation between the shallow and deep aquifer systems.129
124 Id. at 2-8. 125 Id. at Appendix A, p.1. 126 Id. 127 Id. at Appendix A, p.3. 128 Id. at Appendix A, pp.4-6. 129 Id. at Appendix A, p.10. 46 AUGUST 25, 2011
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• Based on both water level and quality data, it was concluded that the Sonoma Volcanics are hydraulically separated from both the Napa River and the shallow alluvial Aquifer system.130
4.2.4.2 The 2008 Test
In the 2008 aquifer test, Stetson drilled and constructed a new groundwater production well on the Project site, known as NRP-01. Well NRP-01 was drilled to a depth of 766 feet bgs, of which the top 120 feet penetrated the alluvium and the bottom 646 feet penetrated the Sonoma Volcanics. The well was fitted with a 10-inch diameter casing and sealed to 132 feet bgs to ensure that the well draws groundwater exclusively from the Sonoma Volcanics aquifer. The well was developed at pumping rates up to 1,300 gpm and exhibited free-flowing conditions once developed.131
Elements of the 2008 aquifer testing program included pre-test monitoring, step drawdown testing, constant rate testing and water level recovery data collection. Well NRP-01 was used as the pumping well, and observation data were collected from the Napa River, the younger and older alluvium (Wells DW-1 and MW-2) and the Sonoma Volcanics (Syar, Bio Cell and No. 3 Wells). Observation data were collected before, during and after the pumping test, and were adjusted to correct for barometric pressure and tidal influence.132
A step drawdown test was performed on October 29, 2008. Stetson pumped Well NRP-01 at successively increasing rates of 533, 706, 894 and 1,106 gpm for approximately three hours each. Maximum drawdown in NRP-01 was recorded at approximately 56 feet during pumping at the highest rate.133 Based on these results, the rate for the constant rate test was set at approximately 1,000 gpm.
A constant rate test was performed between October 30 and November 1, 2008 and involved pumping Well NRP-01 at an average of 1,021 gpm for 50 hours.134 The impact on all observation points is shown in Table 11. There was no drawdown in the Napa River or shallow Wells MW-2 and DW-1, which was the expected result based on the lack of hydraulic connection between the Napa River and the younger and older alluvium on one hand, and the Sonoma Volcanics aquifer on the other.135 The maximum drawdown in Well NRP-01 was 52.50 feet. The maximum drawdown at the Syar Well and Well No. 3 was 4.16 and 3.39 feet, respectively. Pumping of Well NRP-01 had no measurable effect on the Bio Cell Well, located approximately 2,754 feet south of Well NRP-01. Thus, groundwater levels were not affected at the southern boundary of the Project site. Water levels recovered almost instantaneously after the conclusion of the constant rate test.136
Using the data collected in the constant rate test, Stetson estimated that the hydraulic conductivity of the Sonoma Volcanics in the vicinity of Well NRP-01 is 66 feet per day, and the
130 Id. 131 Id. at 3-2. 132 Id. at 3-3, 3-4, 3-5. 133 Id. at 3-4. 134 Id. at 3-6 135 Id. at 3-7. 136 Id. at Figure 17.
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storativity is 0.00045, using Theis analysis. Stetson also performed a Moench analysis that applies to relatively impermeable fractured rock and determined that the hydraulic conductivity of fractures would be 38 feet per day, and the storativity would be 5.6E-7.137
Table 11. Impact on Observation Points During Constant Rate Aquifer Test Distance from Maximum NRP-01 Drawdown Observation Point Location (feet) (feet) Napa River Napa River 1,554 0 MW-2 Younger Alluvium 419 0 DW-1 Older Alluvium 661 0 NRP-01 Sonoma Volcanics 0 52.50 Syar Sonoma Volcanics 287 4.16 Well No. 3 Sonoma Volcanics 1,207 3.39 Bio Cell Sonoma Volcanics 2,754 0 Source: Stetson Report, at 3-6, Table 9 [Exhibit C].
4.2.5 Groundwater Quality
The evaluation of groundwater underlying the Project site in the Sonoma Volcanics aquifer by Stetson showed that the water quality is sufficient to be a source of drinking water. In May 2007, water samples from the Suscol Well, the Napa River and an observation well on the Project site were sent to a California State Certified laboratory for a general chemistry analysis. An additional seven water samples were collected in November 2008 and analyzed for a number of metals, pH, hardness, total solids, TDS, salinity and chlorides.138
Samples show that groundwater from the Sonoma Volcanics aquifer on the Project site meet all primary drinking water standards.139 Removal of iron and manganese may be required to meet national secondary standards for drinking water, and treatment technology for those minerals is widely used within the water utility industry.140 Iron and manganese present aesthetic issues, but neither poses a health hazard.141 Water quality data collected by Stetson are generally consistent with prior studies that have been conducted in the Suscol area.142
Only basic disinfection is required to meet the standards for all constituents that are regulated under the federal Safe Drinking Water Act and by the California Department of Health Services. HSE has designed the potable water system for the Project to include a 500-gpm iron and manganese water treatment system to be constructed after completion of water quality testing for
137 Id. at 3-7. 138 Id. at 2-14. 139 Id. at 2-15, Table 6. 140 Id. at 2-16, Table 6; HSE Report, §§ 2.4.1, 5.1 [Exhibit A]. Secondary standards are recommended but not required for human consumption, since they are not health-based but typically cover aesthetic issues. 141 HSE Report, § 2.4.1 [Exhibit A]. 142 Stetson Report, at 2-14 [Exhibit C]. 48 AUGUST 25, 2011
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the new wells to be used as potable water sources.143 Detailed information regarding the proposed water treatment facility, including the proposed design and construction of treatment facilities, is found in Exhibit A.144 Based on the data collected by Stetson and the water system designed by HSE, water quality will not restrict the use of groundwater from the Sonoma Volcanics aquifer for purposes of the Project.145
There has been extensive groundwater quality monitoring and remediation in the younger and older alluvium on the Project site due to historical industrial activities. Groundwater contamination is located in the northwest, central and southeast portions of the site, and an extraction system for volatile organic compounds was in operation from January through June 2008. As noted elsewhere in the Stetson Report and this WSA, the occurrence of laterally extensive clay hydraulically separates the deeper confined Sonoma Volcanics aquifer from the alluvial aquifer system. It appears that this clay has effectively restricted the movement of groundwater and contaminants from the shallow alluvium to the Sonoma Volcanics aquifer. No contaminants have been detected in the lower aquifer. Nevertheless, care will be taken when siting groundwater production wells to avoid any possibility of contamination.146
4.3 Groundwater Rights
4.3.1 Legal Classification of Groundwater
In California, waters found beneath the surface of the ground may be legally classified as either “percolating groundwater” or “subterranean streams flowing through known and definite channels,” which are legally classified as surface waters because of their stream-like characteristics.147 Surface waters, including subterranean streams, lie within the permitting jurisdiction of the State Water Resources Control Board (“SWRCB”), but percolating groundwater is not subject to any statewide permitting system or management program to regulate the appropriation or use of water.
4.3.2 Groundwater Rights
In order for the Project to rely on groundwater, the water purveyor for the Project will need to possess a legal right to access that groundwater. In addition, it is important that the groundwater basin be properly managed for groundwater to serve as a reliable long-term supply, and groundwater rights serve as the basis for most management of groundwater resources. For these reasons, this section analyzes the groundwater rights that will be relied upon for the Project. Groundwater rights in California may be of two basic types: overlying and appropriative. The Project will rely on overlying rights, but could also establish appropriative rights if needed in future. The following two sections discuss the two types of right and the manner in which the Project will rely upon each type.
143 See HSE Report, § 5.1 [Exhibit A]. 144 See HSE Report, § 2.4.1 [Exhibit A]. 145 CON UWMP, at 3-7 [Exhibit B]. 146 Stetson Report, at 1-3, 2-16 to 2-18. 147 See CAL. WATER CODE § 1200.
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4.3.3 Overlying Groundwater Rights
The owner of real property overlying a groundwater aquifer possesses a right as part and parcel of the land to extract groundwater from beneath the property for use on overlying land within the watershed.148 An overlying owner may extract water from one point on the property and use it anywhere on the same parcel so long as the use occurs within the watershed or drainage area of the basin.149 Additionally, so long as the property owner’s land actually overlies a portion of the aquifer, there is no legal requirement that the extraction well be located within the four corners of the property.150 There is no requirement that an overlying landowner continuously use the water to maintain a vested right, because the right is part and parcel of the land.151 The overlying right consists of a present right to use water for existing and prospective uses.152 Thus, the right may remain unexercised or dormant, unless a court adjudication provides otherwise.153 Because water rights in the Sonoma Volcanics aquifer remain unadjudicated, the right of a party to pump water from the Basin is not governed by any court order or agreement, but rather by the common law, as set forth here.
An overlying owner’s groundwater right is correlative with all other overlying users’ rights, which means that the overlying owner is entitled to extract and use a proportional and reasonable share of the common supply.154 Absent a court adjudication of groundwater rights, the overlying owner is not limited to any specific quantity of water because, by definition, the amount of water to which the overlying owner is entitled fluctuates with the present need of the landowner.155 Instead of a quantified right, the correlative right is a right to a proportional share of the total water supply in the aquifer, which is limited by the equal and mutual rights of the other overlying landowners.156
An overlying owner enjoys the paramount status and benefit of the overlying right only as long as the water is used for proper overlying uses. Overlying owners, like all water users, are subject to the constitutional prohibition against waste and unreasonable use of water.157 Therefore, all overlying uses must be reasonable, e.g., the manner and method of the use must not be wasteful, and for beneficial purposes, e.g., domestic, irrigation or municipal and industrial use.
Due to the nature of the Project, the occupants of the completed residential and commercial units will not own the lands underlying their units. Instead, ownership will vest in a property owners association (“POA”) or other common interest organization formed to hold and manage the property. Accordingly, the POA will possess the overlying groundwater rights associated with the Napa Pipe property. The POA will have the legal right to drill wells on the property and extract water from the Sonoma Volcanics aquifer for reasonable and beneficial water uses on the
148 See City of Barstow v. Mojave Water Agency, 23 Cal.4th 1224, 1240 (2000). 149 See Scott S. Slater, California Water Law and Policy, at § 3.02 (2006). 150 See Hildreth v. Montecito Creek Water Co., 139 Cal. 22, 29 (1903). 151 City of Pasadena v. City of Alhambra, 33 Cal.2d 908, 925 (1949). 152 See Peabody v. City of Vallejo, 2 Cal.2d 351 (1935). 153 In an adjudication, a court officially determines the rights of all parties claiming an interest in the supply and enters an injunction against any party’s pumping in excess of their rights. 154 See Katz v. Walkinshaw, 141 Cal. 116 (1903). 155 See Prather v. Hoberg, 24 Cal.2d 549, 559-60 (1944). 156 See Barstow, supra, 23 Cal.4th at 1241. 157 CAL. CONST., ART. X, § 2. 50 AUGUST 25, 2011
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property. The POA’s overlying right will entitle it to extract and use groundwater anywhere on the property, since the entire Project site overlies the aquifer. The POA’s proposed uses of groundwater—for residential, commercial and industrial uses and landscape irrigation—all constitute beneficial uses.158 As noted above, the actual point of extraction of groundwater does not have to be located on a particular parcel in order for that landowner to successfully claim the use to be overlying. Thus, as the owner of several overlying parcels, the POA may use a well on one parcel to supply water to all Project parcels based on the exercise of overlying rights.159
In addition, the POA will appoint the water purveyor as its agent for exercise of overlying groundwater rights through what is known as a “groundwater agency agreement.” Under such an arrangement, the water purveyor will exercise the overlying rights of the POA on its behalf on a permanent, irrevocable basis.160 The type of water purveyor ultimately selected for the Project—public utility, mutual water company, special public district or CON—is inconsequential, since each type of entity may act pursuant to a valid groundwater agency agreement. Because overlying rights are paramount over appropriative rights, such an agreement will insulate the POA from the risk of having its rights subordinated to appropriators from the groundwater basin. Such an arrangement will provide the Project with a firm, reliable entitlement to extract and use groundwater for the Project.
The owners of the Project site have been using groundwater pursuant to overlying rights since the early 1900s. Thus, those overlying rights are well established and cannot be argued to have been lost through prescription to any other overlyer or appropriator. If in future there is an overpumping of groundwater in the Napa Valley generally, the Project will be entitled to participate in management or adjudication of the groundwater resource on an equal basis with other landowners, such as agriculturalists and rural residents.
4.3.4 Appropriative Groundwater Rights
An alternative method for the Project to gain groundwater rights would be for the water purveyor to commence pumping and delivering groundwater to its customers for use on the Project site and thereby establish an appropriative right.
Appropriative rights, unlike overlying rights, are not based on ownership of land, but are created by the extraction and use—together called “appropriation”—of groundwater. Formation of an appropriative groundwater right requires that three elements be satisfied: (1) an intent to appropriate water; (2) actual extraction of groundwater; and (3) application of the extracted water to reasonable and beneficial use.161 Unlike overlying rights, appropriative rights are quantified, based upon the amount of extraction and use that has been established. Appropriative rights are more flexible in the place of use than overlying rights, but are subordinate in priority in case of shortage of the water supply, so that appropriative groundwater rights may be used only if there is surplus water available in a basin after satisfaction of all overlying groundwater
158 See CAL. WATER CODE § 106. 159 See Burr v. Maclay Rancho Water Co., 154 Cal. 428, 434 (1908). 160 For cases upholding agency agreements, see Hildreth v. Montecito Creek Water Co., 139 Cal. 22, 29 (1903), Stratton v. Railroad Commission, 186 Cal. 119 (1921), and Rancho California Water District v. Gomez, slip opin., Case No. E025699 (4th App. Dist. 2000) (unpublished decision). 161 See Slater, supra, at Part E, § 2.09.
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rights.162 The one exception to this latter rule is that appropriative rights may move their priority in front of unexercised overlying rights, if the appropriative rights develop into prescriptive rights.163
The formation and use of appropriative groundwater rights is not preferred for the Project because those appropriative rights would be subordinate to overlying rights in the Basin and junior to other previously-formed appropriative water rights. Nonetheless, because there has not been extensive historical appropriation of groundwater within the Basin, and overdraft conditions have not been determined to exist, there is water available in the Basin in which a water supplier may form appropriative rights. The Project will only rely on appropriative rights to the extent that it is necessary after exercising overlying rights.
It should be noted that if either CON or AmCan decided to begin withdrawing groundwater, as discussed in Section 4.6, it would do so through the development and exercise of appropriative rights. Those rights would be subordinate to the overlying rights of the Project, agriculturalists and rural residents who pump and use groundwater on their own parcels.
4.3.5 Basin Management
California has not implemented a comprehensive statewide program to regulate or manage groundwater resources. As a result, the regulation of groundwater has largely been left to local authorities. Local agencies that want to preserve and manage groundwater in their region may establish their own groundwater management programs.164 These management programs do not displace groundwater rights, but simply add a resource management overlay to the existing water rights framework. Because no two groundwater basins are identical, local basin management programs differ in purpose and scope. Typically, local groundwater management strategies include monitoring groundwater levels and production amounts, cooperative arrangements among pumpers to minimize or eliminate problem conditions, and, where applicable, conjunctive use of groundwater and surface water supplies.
162 See City of San Fernando v. City of Los Angeles, 14 Cal.3d 199, 285-86 (1975); City of Pasadena, supra, 33 Cal.2d at 928-32. 163 In order for an appropriator to establish a prescriptive right, the appropriator must establish that it appropriated water in excess of the basin’s safe yield for at least five years pre-dating the filing of any action to determine the parties’ rights in the basin, and that overlying owners had notice (actual or constructive) of the adverse taking. See generally Barstow, supra, 23 Cal.4th 1224; City of Los Angeles v. City of San Fernando, 14 Cal.3d 199 (1975). The primary indication of a groundwater basin that may be subject to the acquisition of prescriptive rights is the existence of overdraft, a condition that results from groundwater extractions that exceed the basin’s safe yield. There is no indication that the Sonoma Volcanics aquifer in the Suscol area, the Napa Valley Subbasin or the Napa- Sonoma Valley Groundwater Basin is experiencing or ever has experienced overdraft. See Stetson Report, at 1-1 [Exhibit C]. 164 Cities and counties are imbued with the “police power,” which authorizes them to make and enforce within their limits all local, police, sanitary and other ordinances and regulations not in conflict with the general laws of the state. See CAL. CONST., ART. XI, § 7. Generally, cities and counties have been held to possess some police power authority relating to regulation of groundwater. See In re Maas, 219 Cal. 222 (1933); Baldwin v. Tehama County, 31 Cal.App.4th 166 (1994) (upholding a county ordinance prohibiting the export of groundwater from the county). 52 AUGUST 25, 2011
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Groundwater rights in the Suscol area have not been the subject of a court adjudication, and no groundwater management plan has been adopted by any agency with proper authority.165 Thus, the basin is currently unmanaged in a comprehensive system.
4.3.6 County Groundwater Policies and Ordinances
The County has addressed groundwater resources in two ways. First, the County has adopted an ordinance that provides limited regulation of groundwater withdrawals. Second, the Napa County General Plan includes two provisions related to conservation and use of groundwater.
In 1999, the Napa County Board of Supervisors approved a groundwater management ordinance that requires a person to obtain a permit before extracting any groundwater within the County, under certain circumstances that will apply to the Project.166 A permit cannot be issued if substantial evidence exists showing that the proposed project will adversely impact the basin in which it is located. Some of the factors that the Director of Environmental Management will consider are: “impact on the affected groundwater table; adverse effects on the reasonable and beneficial uses of groundwater; interference with surface water flows; implementation of Best Management Practices; or other adverse changes to the physical environment.”167
A groundwater permit will be acquired for the Project pursuant to the Napa County groundwater ordinance. Based on technical studies conducted to date and discussed in this Section 4, no evidence exists to show that the extraction of groundwater for the Project would cause any of the adverse impacts listed above. Therefore, there is no significant reason to believe that Napa County would not issue a groundwater permit for the Project. In fact, not only will the Napa County groundwater ordinance not impair the ability of the Project to rely upon local groundwater resources, it will tend to support the reliability of that water supply by regulating other uses that might interfere with the Project’s paramount overlying rights.
In discussions related to the Project, some members of the public have referenced the “fair share” allotment of groundwater pursuant to the Napa County groundwater ordinance. The ordinance does not limit the quantity of groundwater that may be extracted by an overlying landowner, but as set forth above simply requires a new water system that proposes to use groundwater to obtain a groundwater permit from the County.168 Such a permit may be ministerial or discretionary. A water system may obtain a ministerial permit based on an application for a minor modification of an existing groundwater permit, if the requested quantity does not exceed the fair share standard for the parcel as established in the Department of Public Works Water Availability Policy Report.169 The current standard for the Suscol area is 1.0 AFY per acre. Another example is that an agricultural user may obtain a ministerial permit within the MST area if the quantity requested does not exceed 0.30 AFY per acre.170 In either area, an applicant may file a request with the County for a discretionary permit in any amount, i.e., not limited by the 1.0 AFY or 0.30 AFY
165 See CAL. WATER CODE §§ 10750 et seq. (providing authority for adoption of groundwater management plans). 166 See NAPA COUNTY CODE §§ 13.15.020(A)-(C), 13.15.010(C). Napa County also enacted special guidelines for the MST area, which is considered to be near or in overdraft. As noted above, the Project is not located within the MST area. 167 See NAPA COUNTY CODE § 13.15.070(C). 168 See NAPA COUNTY CODE § 13.15.020. 169 NAPA COUNTY CODE § 13.15.030.D. 170 NAPA COUNTY CODE § 13.15.030.C.2.
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quantities.171 The purpose of the fair share allotment is to provide for a minimum amount of groundwater that a landowner may withdraw without undertaking costly technical review. The allotment is not intended, however, to limit the withdrawals of a landowner who is willing to undertake a significant technical review of available groundwater, such as has been completed by the Project. As discussed above, the Project will extract groundwater pursuant to a discretionary permit, and therefore the fair share standard has no application to the Project.
In addition to the groundwater management ordinance, the County has adopted two groundwater-related policies in its General Plan, Conservation Goal CON-11 and Policy CON-51. Those provisions read as follows:
Goal CON-11: Prioritize the use of available groundwater for agricultural and rural residential uses rather than for urbanized areas and ensure that land use decisions recognize the long-term availability and value of water resources in Napa County.
Policy CON-51: Recognizing that groundwater best supports agricultural and rural uses, the County discourages urbanization requiring net increases in groundwater use and discourages incorporated jurisdictions from using groundwater except in emergencies or as part of conjunctive-use programs that do not cause or exacerbate conditions of overdraft or otherwise adversely affect the County’s groundwater resources.172
These policies evince a desire by the County to maintain the historical balance of groundwater use between agricultural, rural residential and urban citizens and preserve adequate groundwater resources for use by future vineyards that contribute to the County’s character and economy. The use of groundwater for the Project is consistent with these policies because it involves reuse of a previously urbanized site with a long history of substantial groundwater use. The site does not contain existing or former agricultural uses, and as discussed in Sections 4.5, 4.6 and 4.7, the withdrawal and use of groundwater for the Project is not anticipated to have any significant impact on existing or planned future agricultural or rural residential uses of groundwater in the Suscol area. Even with withdrawals of groundwater for the Project, significant surplus groundwater will exist in the Sonoma Volcanics aquifer in the Suscol area. Thus, the Project will both maintain the historical balance of groundwater uses in the County and preserve the resource to support future agricultural growth.
Following the language of the County policies, approval of the Project would “recognize the long-term availability and value of water resources in Napa County” and not constitute “urbanization requiring net increases in groundwater use.” Although the Project would not be located in an incorporated jurisdiction, it would “not cause or exacerbate conditions of overdraft or otherwise adversely affect the County’s groundwater resources.”
The Project applicant has proposed limited amendments to Goal CON-11 and Policy CON-51 in order to clarify the consistency between the Project and these policies. The amendments are
171 NAPA COUNTY CODE § 13.15.060. 172 Napa County General Plan (June 23, 2009) [http://www.countyofnapa.org/GeneralPlan/]. 54 AUGUST 25, 2011
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useful to establish that the Project is consistent with County policies in a manner that would not be broadly applicable to other parcels that may be subject to development applications in the future. As discussed in this Section 4 generally and Sections 3.1 and 4.2.3 specifically, the Project site is unique within Napa County for its location overlying a productive groundwater aquifer and long history of groundwater extraction and use.
County General Plan provisions Goal CON-11 and Policy CON-51 must be understood in the context of California state policy on water use. The California Constitution, article X, section 2, which was adopted by the voters in 1928, provides that: “[i]t is hereby declared that because of the conditions prevailing in this State the general welfare requires that the water resources of the State be put to beneficial use to the fullest extent of which they are capable, and that the waste … of water be prevented, and that the conservation of such waters is to be exercised with a view to the reasonable and beneficial use thereof in the interest of the people and for the public welfare.” As described by a well-respected commentator, “[t]he policy inherent in the State water law is to utilize all water available; … and to require the greatest number of beneficial uses that the water supply can yield.”173 Thus, the County General Plan cannot be interpreted to adopt a policy favoring non-utilization of the state’s valuable groundwater resources, but instead the protection of beneficial groundwater uses. Given the abundance of renewable groundwater underlying the Project site, it is consistent with the fundamental state water policy to allow the Project to use that groundwater.
4.4 Hydraulic Separation of the Sonoma Volcanics Aquifer
Pertinent literature, borehole lithologic data, data collected during the 2007 passive monitoring program, the results of the aquifer test in 2008 and more recent water level measurements demonstrate that the Sonoma Volcanics aquifer system below the Project site is highly confined and hydraulically separated from both the shallow alluvial aquifer system and the Napa River. The hydraulic separation is important for the Project for two primary reasons. First, because groundwater found in the Sonoma Volcanics aquifer is not connected to the subflow of the Napa River or any subterranean stream, it is legally classified as percolating groundwater and is not subject to the water rights permitting system administered by the SWRCB.174 Second, use of the Sonoma Volcanics groundwater for municipal and industrial purposes is not subject to the treatment requirements of the U.S. Environmental Protection Agency’s Surface Water Treatment Rule for groundwater under the influence of surface water.175 Due to the significance of the finding of hydraulic separation, specific evidence is summarized below.
First, on-site and off-site lithologic information obtained from well logs strongly indicates the existence of laterally extensive fine-grained materials, including clay in the alluvial deposits of the Suscol area. These materials have been discovered in the borings for every well in the Suscol area for which a well log is available, which demonstrates their lateral extensiveness.176
173 Wells A. Hutchins, The California Law of Water Rights, at 11 (1956), citing City of Pasadena v. City of Alhambra, 33 Cal.2d 908, 925 (1949); Allen v. California Water & Telephone Co., 29 Cal.2d 466, 488 (1946). 174 See CAL. WATER CODE § 1200 (extending jurisdiction to “surface water, and to subterranean streams flowing through known and definite channels”). 175 See 40 C.F.R. §§ 141.71-141.76 (2005). 176 Id. at 1-2 (citing Kunkel & Upson), 1-3, 2-2, 2-3, 3-2.
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Second, groundwater levels in the shallow alluvial aquifer system and the deeper Sonoma Volcanics aquifer system have been documented to be distinctly different from each other, indicating a high degree of hydraulic separation between the aquifer systems. Specifically, groundwater levels, as measured by hydraulic heads, in the Sonoma Volcanics aquifer have been documented to be consistently greater than in the alluvial aquifer system. Historical and recent observations document groundwater levels in the Sonoma Volcanics aquifer that are above the ground surface, yielding free-flowing wells, i.e., wells that yield water to the surface without pumping. These observations provide evidence for highly confined conditions in the Sonoma Volcanics aquifer and the existence of an effective, laterally continuous, aquitard in the Suscol area.177
Third, as described in Section 4.2.4.2 of this WSA, the aquifer test performed in 2008 by Stetson demonstrated that groundwater pumping at Well NRP-01 in the Sonoma Volcanics did not have any impact on groundwater levels in the alluvial deposits. During the 50-hour constant rate pumping test performed in October 2008, there was no drawdown in the shallow alluvial wells MW-2 and DW-1.178 As noted in the Stetson Report, “[b]oth DW-1 and MW-2, completed in the older alluvium and younger alluvium, respectively, showed no change in water levels due to aquifer test pumping. The data from these wells indicate there is no communication between the Sonoma Volcanics and the overlying alluvial basin fill.”179
Lastly, groundwater quality data indicate that the Sonoma Volcanics are isolated from the Napa River and the younger and older alluvium.180 Table 6 of the Stetson Report compares the general groundwater chemistry of the Napa River, the younger alluvium (Well DW-7), the older alluvium (Well Obs-OA1) and the Sonoma Volcanics (the Suscol and NRP-01 wells).181 In addition, Figure 14 to the Stetson Report is a Piper Diagram that presents a graphical relationship between common anions and cations in surface water from the Napa River and groundwater underlying the Project site. Based on those comparisons, the water samples fall into three distinct groups—from the Napa River, older alluvium and Sonoma Volcanics—with separate quality characteristics for each group. For example, groundwater in the Napa River (8,110 mg/L total dissolved solids) and older alluvium (9,070 mg/L) are brackish when compared to the Sonoma Volcanics (450 mg/L). Specific conductance in the Napa River (10,100 umhos/cm) and older alluvium (12,800 umhos/cm) are high when compared to the Sonoma Volcanics (650 umhos/cm). There are also differences in calcium levels between the Napa River (120 mg/L), older alluvium (920 mg/L) and Sonoma Volcanics (40 mg/L), and differences in other constituents such as magnesium, potassium, sodium, chloride and sulfate. These significant water quality differences provide additional evidence for hydraulic separation of the deep confined Sonoma Volcanics aquifer from both the shallow unconfined alluvial aquifer system and the Napa River.182
177 Id. at 2-4, 2-5. 178 Id. at 3-6. 179 Id. at 3-7. 180 Id. at 2-5, 2-14. 181 Id. at 2-15, Table 6. 182 Id. at 2-15, 2-16. 56 AUGUST 25, 2011
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4.5 Groundwater Supply Estimate
The Sonoma Volcanics aquifer in the Suscol area is supplied with groundwater via two mechanisms: subsurface inflow from the north and rainfall-recharge in the Howell Mountains east of the Project site. To estimate available groundwater supplies in the Suscol area for the Project and other water users, Stetson approximated these quantities as follows.
The potential groundwater inflow into the Suscol area was estimated based on (i) aquifer characteristics derived from the 2008 aquifer test, (ii) a cross-sectional area assuming an average aquifer thickness of 500 feet between the West Napa Fault (located just west of the Napa River) and the nearest outcrop of the Sonoma Volcanics in the hills on the eastern side of the Suscol area, and (iii) historical groundwater gradients observed in this area when pumping stresses were likely comparable to Project pumping stresses. It was estimated that 2,700 AFY of groundwater inflow to the Suscol area can be expected under these conditions. While uncertainty regarding the assumptions is recognized, this estimate appears reasonable, and it is possibly low, as the average thickness of the Sonoma Volcanics aquifer used for the calculation was purposefully conservative.183
Local recharge originating as rainfall in the Howell Mountains east of the Project site was estimated based on a 3,300-acre drainage area, most of which is composed of exposed volcanic rock. Recognizing similarities to the Howell Mountains northeast of the Project site, i.e., the source area for rainfall-recharge to the MST area, such as rock types, slopes and drainage patterns, infiltration characteristics were assumed to be similar. Using the actual average annual precipitation in the area east of the Project site, which is 28 inches per year, and a rainfall-to- recharge relationship (10.5 percent) derived from a prior study, Stetson calculated the average rainfall-recharge for this area to be 800 AFY. To avoid potential methodological overestimation, recharge from the east was reduced 50 percent from 800 AFY to 400 AFY.184
Based on the calculations above, the combined amount of groundwater from both subsurface inflows and local recharge available in the Sonoma Volcanics aquifer in the vicinity of the Project site is estimated to be at least 3,100 AFY. As reported in the 2050 Study based on hydrographs in the Napa Valley from 1930 through 2002, groundwater levels in the Napa Valley Subbasin have historically been steady and have not varied significantly from year to year across wetter and drier periods. Thus, the 3,100 AFY should be available as a long-term average supply under varied hydrologic conditions, i.e., in normal, single dry and multiple dry years.
4.6 Other Local Groundwater Users
This section describes the use of local groundwater supplies from the Sonoma Volcanics aquifer in the Suscol area by others. The Sonoma Volcanics aquifer is tapped by a relatively small number of current groundwater users in the Project vicinity. In the future, there is one planned expansion by a vineyard located east of the Project site.185 Also, the Syar Industries Quarry plans to expand its mining operations. A map showing the various groundwater users is attached
183 Stetson Report, at 2-11, 2-12 [Exhibit C]. 184 Id. at 2-11, 2-12. 185 See County of Napa, Napa County Baseline Data Report, “Groundwater Hydrology”, at 16-3 (November 2005) [http://www.napawatersheds.org/docs.php?oid=13358&ogid=10112].
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as Figure 19 to the Stetson Report. Baseline and projected increases in pumping by all landowners from the Sonoma Volcanics aquifer in the Suscol area are shown in Table 12. The water use by each entity other than the Project is also described in the following sections.
Table 12. Baseline and Projected Future Increased Pumping, Suscol Area Projected Baseline Increase in Entity Pumping Pumping Total Napa Pipe Project 150 470 620 CON 0 0 0 AmCan 0 0 0 Vineyards 714 273 987 Syar Industries Quarry 50 0 50 Kennedy Park Golf Course 0 0 0 Total 910 740 1,660 Source: Stetson Report, at 4-4 to 4-6, Table 11 [Exhibit C]. All figures expressed in AFY. Totals rounded to the nearest 10 AFY.
4.6.1 City of Napa
As described in Section 7.3 of this WSA, CON meets its water demands from three major sources: Milliken Reservoir; Lake Hennessey; and SWP water delivered through the North Bay Aqueduct. According to the most recent urban water management plan adopted by CON in 2011, the “City of Napa currently relies on surface water supplies exclusively and has no programs in place involving groundwater or conjunctive use.”186 CON did, however, identify potential groundwater options that it may consider in future:
One involves handling excess SWP entitlements by storing the water in groundwater wells along the [North Bay Aqueduct] pipeline in Solano County. The others involve the use of new or existing wells in the local groundwater basin. Potential new wells would include a municipal well to be used exclusively for dry year or emergency supplies and on-site wells to provide non-potable water for schools and parks.187
The CON UWMP in 2005 added that:
There are a number of large wells on the former Napa Pipe industrial site. If this site is developed in the future, the existing wells could potentially meet the site’s water demands.188
186 City of Napa, Urban Water Management Plan 2010 Update, at 3-7 (June 2011). 187 Id. 188 CON UWMP, at 3-7 [Exhibit B]; 2050 Study, Tech. Memo No. 7 at 12 [Exhibit D]. See also West Yost & Associates, Technical Memorandum: Feasibility Level Evaluation of the Groundwater Supply Available from the 58 AUGUST 25, 2011
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In addition, in 2005 CON commissioned WYA to perform a study of the feasibility of supplementing its surface water supplies with groundwater from the Napa Pipe Project site. As described in Section 4.1 of this WSA, WYA did not find any reason that such groundwater use would be infeasible and recommended that CON consider acquiring groundwater rights for the site, but CON did not make any such acquisition or take other steps toward the use of groundwater.189
Based on the representation by CON in its UWMP, there is no currently planned competition for groundwater supplies with CON. Groundwater usage by the Project will not have any negative impact on CON’s water utility operations, and CON’s operations will not have any adverse effect on the ability of the Project to meet its water demands with local groundwater.190
4.6.2 City of American Canyon
The City of American Canyon (“AmCan”) is located to the south of the Project site and operates its own water and wastewater utility systems. Like CON, AmCan meets its water supply needs exclusively with surface water, in the case of AmCan through: (i) imported SWP supplies; (ii) raw and treated water purchases from the City of Vallejo; (iii) treated water purchases from CON; (iv) recycled water from AmCan’s wastewater treatment plant; and (v) recycled water from the NSD wastewater treatment plant.191 To meet future demands, AmCan plans to expand its delivery of recycled water to customers within its service area.192 AmCan is in the early stages of studying construction of a new reservoir, named the Garden Bar Project. According to the AmCan 2010 UWMP, “[t]his project is very preliminary at this stage and no definitive information is available at this time.”193
AmCan does not currently utilize groundwater as a source of supply.194 In its planning processes, AmCan has conducted a preliminary groundwater analysis to consider the potential for groundwater as a source of water.195 It found that the shallow groundwater beneath the valley floor within the city is derived from mostly older alluvial floodplain and fan deposits, and as such the shallow wells drilled in the alluvium are under-producing and not reliable water sources during dry months.196 The few deep wells in the area (approximately 400 feet deep) have been found to be brackish and not sustainable. AmCan does not have access to the Sonoma Volcanics aquifer within its water service area.
As stated in its most recent planning document, “[a]t this time, the City does not intend to explore groundwater as a viable municipal water source.”197 Although AmCan has identified the possibility of using groundwater for raw water irrigation and as an emergency supply, its
Napa Pipe Corporation Facility for Use as a Municipal Supply, Project No. 424-02-05-03.01 (August 16, 2005) [Exhibit E]. 189 See footnotes 94-95 and accompanying text, supra. 190 Stetson Report, at 4-4 to 4-5 [Exhibit C]. 191 AmCan 2010 UWMP, at 4-1; AmCan 2005 UWMP, at 4-1. 192 AmCan 2010 UWMP, at 4-7 through 4-14; AmCan 2005 UWMP, at E-6. 193 AmCan 2010 UWMP, at 4-14. 194 AmCan 2010 UWMP, at 4-1; AmCan 2005 UWMP, at E-2. 195 AmCan 2010 UWMP, at 4-6; AmCan 2005 UWMP, at 4-7. 196 AmCan 2010 UWMP, at 4-6; AmCan 2005 UWMP at 4-7. 197 AmCan 2010 UWMP, at 4-6; AmCan 2005 UWMP at 4-7.
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investigation is preliminary, no definitive information is available and such use would be speculative for purposes of this WSA. In its most recent planning document, AmCan did not identify any quantity of groundwater in its future water supplies.198 Accordingly, AmCan will not likely be competing with the Project for groundwater supplies.199
AmCan has claimed in the past that it possesses groundwater rights in supplies underlying the Suscol area as the result of being the successor in interest of a private water company acquired by the American Canyon County Water District. This WSA does not include an opinion regarding whether such groundwater rights ever existed or whether AmCan has maintained, forfeited or abandoned any such groundwater rights that may have existed in the Suscol area, since these questions are irrelevant for purposes of this WSA and local groundwater supplies for the Project. Whether AmCan were to exercise previously existing or new appropriative groundwater rights for any future groundwater production would not matter, because any such appropriative rights would be subordinate to the paramount overlying groundwater rights being exercised for the Project. The cumulative needs of all overlying owners (such as agriculture and the Project) must be satisfied before an appropriator (such as AmCan or CON) may take any water surplus to the needs of the overlying owners.200
AmCan has also publicly stated that groundwater rights for the Project are uncertain in light of the fact that groundwater rights in the Suscol area have not been adjudicated. The fact that local groundwater supplies are unadjudicated, however, does not mean that the Project has insufficient rights to groundwater. An adjudication is a useful legal technique for defining the safe yield of a basin and determining whether the basin is in a state of overdraft.201 The two concepts combine to establish an overall maximum amount of water that can be extracted, and an adjudication typically establishes the proportionate share of each user to the common water supply. As explained above, the existence of overlying groundwater rights does not depend upon the occurrence of an adjudication, but such rights are part and parcel of the land whether an adjudication has occurred or not. Any future adjudication would be required to respect the Project’s overlying rights.202 Thus, speculation that groundwater supplies in the Suscol area may someday be subject to adjudication does not eliminate or cause uncertainty regarding the Project’s overlying rights.
4.6.3 Vineyards
There are approximately 593 acres of existing vineyards east of the Project site and State Road 221 against the hills of Napa Valley. These vineyards rely on groundwater for irrigation supplies and are estimated to use approximately 714 AFY based on the average irrigation water use of 1.2 AFY per acre for vineyards in Napa County during 2001.203
198 AmCan 2010 UWMP, at 4-14, Table 4.11. 199 See Stetson Report, at 4-5 [Exhibit C]. 200 See City of Los Angeles v. City of San Fernando, 14 Cal.3d 199, 282-86 (1975); City of Pasadena v. City of Alhambra, 33 Cal.2d 908, 925-26 (1949). See also Scott S. Slater, California Water Law and Policy § 9.02.3 (2010); Wells A. Hutchins, The California Law of Water Rights 455 (1956). 201 See generally City of Pasadena, supra. 202 See City of Barstow v. Mojave Water Agency, 23 Cal.4th 1224, 1242, 1247 (2000). 203 Id., citing MST Report [Exhibit G]. 60 AUGUST 25, 2011
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In addition, Stetson accounted for groundwater use on future vineyards in its evaluation. Based on information obtained from Napa County, SPP Napa Vineyards LLC has plans to plant and irrigate approximately 455 acres of new grapes within the Suscol area. The planned groundwater use for that project is expected to be 273 AFY.204
4.6.4 Syar Industries Quarry
The Syar Industries Quarry is located approximately one mile northeast of the Project site.205 It operates a well for on-site operations. No water use records were available for the preparation of this WSA, but Stetson estimated that annual water use is approximately 50 AFY.206 These demands are included in the analysis of cumulative impacts below. In June 2009, a Notice of Preparation was issued identifying the County of Napa as the lead agency for development of an EIR addressing a 291-acre expansion of the Syar Industries Quarry. Changes in existing and future groundwater requirements, and their related impacts, will be addressed in the Syar Quarry EIR and incorporated in future Syar site-related monitoring plans.
4.6.5 Kennedy Park Golf Course
The Kennedy Park Golf Course is located 0.25 miles north of the Project site. The 126-acre course was historically irrigated with groundwater, but is now irrigated with recycled water supplied by NSD. The course uses approximately 504 AFY of recycled water. There are no plans to stop using recycled water in favor of higher quality potable water supplies, and such a conversion would be contrary to public policy, as described in Section 3.3 of this WSA.207 Because no groundwater is used on the golf course, its operations do not affect the availability of groundwater in the Sonoma Volcanics aquifer for the Project or other groundwater users. Likewise, groundwater extractions for the Project can have no impact on the golf course and its operations.
4.6.6 Summary of Groundwater Users
In summary, the Sonoma Volcanics aquifer is currently tapped by a relatively small number of groundwater users in the Project vicinity. Beyond present use of approximately 150 AFY on the Project site, only one area of existing vineyards east of the Project site and the Syar Industries Quarry north of the Project site were identified, for total current (baseline) groundwater use of 910 AFY. In addition, SPP Napa Vineyards LLC plans new vineyard acreage farther east. The combined increase in groundwater demands—470 AFY due to the Project plus 273 AFY due to new vineyards—is estimated to be 740 AFY, yielding future total groundwater production of 1,660 AFY.
As described in Section 4.3, the long-term groundwater supply of the Sonoma Volcanics aquifer in the Suscol area is at least 3,100 AFY. Due to the long-term nature of groundwater inflow and
204 Id. Since issuance of the Stetson Report, this project has been renamed the Suscol Mountain Vineyards and is projected to use up to 266 AFY of groundwater. The figures in the Stetson Report were not revised based on this decrease in projected groundwater use because the two projections are substantially similar. See County of Napa Website, “Suscol Mountain Vineyards Project” [http://www.countyofnapa.org/SMV/]. 205 Id. 206 Id. at 4-5, 4-6. 207 Id. at 4-5.
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recharge to the Sonoma Volcanics aquifer in the Suscol area, that supply is available in normal, single dry and multiple dry years. The combined water demands of current groundwater users within that area (910 AFY) create a present surplus of approximately 2,190 AFY. Under future pumping projections (1,660 AFY), there is projected to be a surplus of approximately 1,440 AFY. Thus, groundwater pumping within the Suscol area is not expected to exceed 55 percent of the available groundwater supply.208
4.7 Groundwater Level Impact Analysis
Stetson performed an analysis of the potential impacts on groundwater levels in the Sonoma Volcanics aquifer of the baseline and projected increases in groundwater pumping from the Suscol area, as described above.209 This analysis was conducted to determine what impact groundwater pumping at the Project site would have on neighboring pumpers, and in turn what impacts pumping by neighbors would have on the availability of groundwater at the Project site. Projected declines in groundwater levels were calculated using aquifer characteristics as determined by the 2008 aquifer test and were based on a projected five-year period of pumping.210 Table 13 shows the results of Stetson’s analysis. The projected Project pumping of 620 AFY is estimated to cause 1.0 to 1.2 feet of drawdown at neighboring properties, while pumping at those locations was estimated to impact groundwater levels at the Project site by a range from less than 0.1 to 1.3 feet.
Table 13. Groundwater Level Impact from Pumping of Sonoma Volcanics Aquifer Drawdown at Neighbor Site Drawdown at Project Site from Project from Neighbor Pumping Drawdown Pumping Drawdown Neighboring Pumper (AFY) (ft) (AFY) (ft) East Vineyards 620 1.2 714 1.3 SPP Vineyards 620 1.0 273 0.5 Syar Industries Quarry 620 1.2 50 <0.1 Source: Stetson Report, at 4-6, Table 11 [Exhibit C].
These projected drawdowns are very small and considered insignificant. This is especially true since these estimated drawdowns represent conditions after five years of continuous pumping assuming no groundwater recharge. The modeling approach was deliberately chosen to tend to overestimate Project impacts on neighboring groundwater users.
4.8 Interaction with Milliken-Sarco-Tulucay Basin
In addition to the analysis in Section 4.7 of the impacts of groundwater pumping by the Project and other water users in the Suscol area on each other, the Stetson Report and this WSA address a special concern in Napa County, namely, groundwater conditions in the MST area. While the MST area is not located within the Napa Valley Subbasin (except for a small area of overlap not
208 Id. at 5-1, 5-2. 209 Id. at 4-6 to 4-7. 210 Id. at 4-6. 62 AUGUST 25, 2011
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within the Suscol area), Napa County requires that all new developments of groundwater in the general vicinity of the MST area address the potential for impacts to and by groundwater users in the MST area.
The MST area, as shown on Figure 3, is located off the eastern side of the Napa Valley in a topographic depression that is enclosed on the north, east and south by the Howell Mountains and bounded on the west by the Napa River.211 The MST area is made up of alluvium underlain by the Sonoma Volcanics under variably confined conditions. The principal source of groundwater replenishment to the MST area is lateral flow of groundwater that is recharged in the Howell Mountains to the east of the MST area.212 Groundwater flows in the Sonoma Volcanics formation in the main Napa Valley provide a much smaller amount of recharge to the northwestern edge of the MST area.213
A small amount of groundwater also flows out of the MST area on the southwestern side.214 USGS calculated groundwater flow into and out of the MST area using a cross-sectional analysis and Darcy’s equation, the same analytical method used by Stetson to calculate subsurface inflow into the Sonoma Volcanics aquifer in the Suscol area.215 Based on that method, USGS estimated that inflows in 2000-2001 were approximately 530 AFY and outflows were approximately 1,130 AFY, for a net outflow of 600 AFY leaving the MST area. This value is about 2,050 AFY less than the amount USGS had estimated for 1975. The 2,050 AFY decrease closely matches the estimated increase in groundwater pumpage between 1975 and 2000 for the MST area.216
Groundwater from the MST area is the main source of water supplies for about 4,800 residents living in the lower MST Creeks area, as well as irrigated vineyards and a golf course.217 USGS estimated that groundwater extractions in 2000 were approximately 5,350 AFY, which represented an 80 percent increase over pumping in 1975. That extensive pumping in the area has caused groundwater levels to decline by 25 to 125 feet in three large pumping depressions in the northern and east-central areas of the MST area.218 USGS has recommended that those pumping depressions could best be resolved through reductions in groundwater pumping in the MST area. Nevertheless, groundwater levels have risen over the 1975-2001 period in the southern MST area between Imola Avenue, near Napa State Hospital, and at First Avenue south of North Avenue.219 That is the portion of the MST area that is closest to the Suscol area of the Napa Valley Subbasin.
In summary, the primary source of groundwater replenishment to the MST area is lateral flow of groundwater that is recharged in the Howell Mountains to the east. A much smaller amount of additional groundwater enters the MST area via inflow from the Napa Valley Subbasin along its northwestern boundary. In contrast, the principal source of groundwater replenishment to the Suscol area and Project site is groundwater inflow from the upgradient portion of the Napa
211 MST Report, at 4 [Exhibit G]. 212 Id. at 1, 14, 17. 213 Id. at 19, 21, 59. 214 Id. at 24. 215 Id. at 29. See Section 4.5 of this WSA. 216 Id. 217 Id. at 1. 218 Id. 219 Id. at 44.
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Valley Subbasin in the north. The Suscol area also receives lateral flow of groundwater that is recharged in the Howell Mountains to the east. This recharge area is different and independent of the Howell Mountains recharge area for the MST area.220
In order to evaluate the impact that groundwater extractions in the Suscol area, including for the Project, might have on the MST area, two nearby wells were chosen to represent the areas of interest regarding potential impacts—one located at the Project Site and one located south of the MST area at the location of the Smith Brown Well No. 1, which is approximately 4,700 feet northeast of Well NRP-01.221
Stetson used the Theis method and pumping for the Project of 620 AFY for five years without any recharge to the Suscol area to determine groundwater drawdowns. In addition, because of uncertainties regarding the impact of potential faults in the area, Stetson assumed the greatest possible impact and doubled Project pumping to 1,240 AFY. The result was that Project pumping could impact groundwater levels at Smith Brown Well No. 1 by between 1.3 feet and 2.6 feet. The anticipated decline due to the incremental increase in pumping from recent extractions of 150 AFY to the full Project demands of 620 AFY is between 1.0 and 2.0 feet.222 Based on the Moench analysis, groundwater declines were estimated to range from 1.7 to 3.4 feet. Thus, pumping at the Project site for purposes of meeting the potable water demands of the Project will likely have minimal impact on groundwater levels at the Smith Brown Well No. 1, which is located south of the MST area. Stetson concluded that “[b]ased on the sufficiency of water beneath the [Project site] in the Sonoma Volcanics, distance between the wells, and the occurrence and movement of groundwater in the Sonoma Volcanics, future pumping at the [Project site] should not have significant effects on groundwater availability in the MST area.”223
Stetson also analyzed the impacts on the Smith Brown Well No. 1 due to cumulative pumping of 1,660 AFY over a five-year period in the Suscol area (Theis analysis), which represents the total existing and projected future pumping of all groundwater users in the Suscol area as described in Section 4.6. That analysis estimated that the impact on the Smith Brown Well No. 1 will likely result in drawdown of about 3.1 feet. Drawdowns at the Syar Well on the Project site under the same conditions would be approximately 4 feet. Using Moench analysis, drawdowns were estimated to be 4.0 feet at the Smith Brown Well No. 1 and 5.3 feet at the Syar Well.224
In summary, effects of Project pumping on groundwater levels in the MST area were evaluated based on the same analytical methods employed during the 2008 aquifer test analysis. Groundwater level impacts were calculated at a location of an existing groundwater well located south of the southern boundary of the MST area, i.e., the Smith Brown Well No. 1. Project pumping was estimated to cause up to approximately 3.4 feet of drawdown at the Smith Brown Well No. 1 using the most conservative modeling approach. Therefore, this is likely an overestimate of pumping impacts. Project pumping is expected to have no measurable effect on groundwater levels in the MST area for two additional reasons. First, the MST area is farther away from the Project site than the Smith Brown Well No. 1, and any potential groundwater
220 Stetson Report, at 2-10 [Exhibit C]. 221 Id. at 4-1, 4-2. 222 Id. at 4-3. 223 Id. at 4-4. 224 Id. at 4-7. 64 AUGUST 25, 2011
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level impacts diminish with distance. Second, less confined aquifer conditions have been reported in parts of the MST area, and this translates into smaller groundwater level impacts.
4.9 Groundwater Monitoring and Mitigation Plan
The groundwater investigation performed by Stetson for this WSA, including the field work conducted in 2007, 2008 and 2009, gathered sufficient information to conclude that the Sonoma Volcanics aquifer in the Suscol area can serve as a feasible groundwater supply for the Project. Ongoing groundwater monitoring, however, is useful to allow evaluation of long-term groundwater level and quality trends. A concern particular to the Suscol area pertains to a pumping-induced reversal of the regional gradient in the southern Napa Valley Subbasin potentially causing saltwater intrusion. Creation of a groundwater monitoring and mitigation plan (“GMMP”) will facilitate systematic collection of data that may be used to establish baseline conditions, monitor groundwater trends, assist with long-term management of groundwater resources and detect potential adverse impacts on other groundwater users or the Project. A GMMP will be developed by NRP and the water purveyor at the time of development, although data gathered for purposes of this WSA will begin to support baseline conditions.225
The GMMP developed for use by the water purveyor and local and regional water managers will include:
• The installation of monitoring wells on and off the Project site as determined necessary to track the effects of groundwater withdrawals by the Project or by others, such as groundwater users in the MST area;
• Groundwater elevation and water quality hydrographs to develop climatic trend analysis and seasonal fluctuations;
• Sharing of available water level data with neighboring groundwater users to develop groundwater elevation contours from which to better understand the regional gradient that affects the recharge and groundwater inflow of water towards the Project site;
• Investigation of potential effects of faulting on groundwater levels that may influence groundwater flow at the Project site;
• Monitoring wells screened in different geologic units to verify there is no hydraulic connection between the shallow alluvium and deep Sonoma Volcanics aquifer;
• Collection of water level and quality data from surface water near the Project site to assure there is no connection between the Sonoma Volcanics and the Napa River that might compromise water quality beneath the site; and
• Other monitoring elements that are determined to be appropriate and useful.226
225 Id. at 6-4. 226 Id. at 6-5.
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In order to gather information, the GMMP would set up a network of monitoring wells on and surrounding the Project site and a monitoring station on the Napa River. As data is collected, it will be analyzed and the results incorporated into Best Management Practices (“BMPs”) for management of groundwater resources in the Sonoma Volcanics aquifer. In particular, groundwater data will be evaluated following each development phase for the Project. If observed data differ from the results predicted in this WSA, the Stetson Report and the HSE Report, groundwater pumping may be adjusted by drilling of new wells in different locations on the Project site, greater use of recycled water where possible, or acquisition of supplemental water supplies. Development and use of iterative groundwater management plans is part of normal BMPs for water utilities.227
4.10 Impact of Climate Change on Local Groundwater
This section of the WSA includes a survey of current scientific and policy literature on climate change and a summary of the potential impacts on water resources in California. To address the potential impacts of climate change on Project water supplies, this section reviews the most recent reports that address the potential effects of climate change in the West, and more specifically, in California. For a summary of the specific reports reviewing climate change impacts on water resources as a whole, see Exhibit N.228
Recent climate change reports recognize that impacts on water resources largely depend on the degree of warming and concede there are significant uncertainties regarding the impact of climate change on local and regional climates. There is a great deal of uncertainty surrounding predictions of temperature increases and the resulting impacts on local and regional climates because it is difficult to predict future greenhouse gas emissions and the resulting feedback processes in the climate system and hydrological cycle. Existing climate change models are imperfect and become increasingly imprecise when used to predict changes on a watershed level. Therefore, it is not possible to specifically quantify the impacts of climate change on water supplies in the western United States or California, let alone in Napa Valley or the Project site.229
Although climate change impacts are uncertain and cannot be precisely modeled, existing evidence, including the effects of warming in the West over the last century, demonstrate that climate change will likely affect future snowpack accumulation, water supply, runoff patterns, sea level, incidents of flooding and droughts, evapotranspiration rates, water requirements, water temperature, water quality and invasive species that threaten water supply infrastructure. Water supplies will be directly affected by temperature changes, precipitation, humidity and wind speed. Recent reports are largely in agreement that climate change will produce hydrologic
227 Id. at 6-5, 6-6. 228 It is impracticable for the County or any other preparer of a water supply assessment to produce a new analysis of climate change for a water supply assessment. As noted by David Yates, Project Scientist for the National Center for Atmospheric Research (“NCAR”), at a presentation before the National Association of Water Companies on October 1, 2007, the NCAR climate model has been under construction since the early 1970s and requires approximately 100 days to complete a single run. When compared with the 90-day time limit imposed on the preparation of a water supply assessment, see CAL. WATER CODE § 10910(g)(1), it is clear that the only available option for a water supplier is to rely on published reports from technical experts. 229 This approach to analyzing climate change has been approved by the Los Angeles County Superior Court in a case that addressed the sufficiency of a water supply assessment in an EIR. See Santa Clarita Oak Conservancy, California Oak Foundation, and Santa Clarita Organization for Planning the Environment v. City of Santa Clarita, Statement of Decision, Case No. BS 084677 (Los Angeles Sup. Ct. August 15, 2007). 66 AUGUST 25, 2011
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conditions and variations of a different nature than current systems were originally designed to manage.
While several studies have examined the impact of climate change on California’s surface water resources, very little research has been conducted on the impacts of climate change on groundwater, namely “for specific groundwater basins, or for general groundwater recharge characteristics or water quality.”230 In fact, while “historic patterns of groundwater recharge may change considerably,”231 it is unknown whether recharge rates will increase or decrease.232 There are some indicators that climate change may, in fact, increase groundwater recharge in many basins. For example, warmer, wetter winters, leading to an increase in the amount and timing of runoff, could increase groundwater recharge.233 Increased temperatures, which cause precipitation to fall as rain instead of snow, could increase the intensity of storm runoff that may overflow stream channels and recharge aquifers. In contrast, the intensity of the runoff could result in additional losses to the oceans.234 Alternatively, decreases in spring runoff and increases in evapotranspiration due to higher temperature could reduce the amount of water available for groundwater recharge.235 Some of that effect would only apply in areas where winter precipitation tends to fall as snow rather than rain. Experts also report that climate change may cause increased salinity intrusions and loss of water storage in coastal aquifers.
One recent report analyzed the effects of climate change on groundwater in California’s Central and West Coast basins in Los Angeles County.236 The report identifies the oft-cited impacts to the state’s surface water supply: reduction of annual snowpack, changes in the timing and intensity of precipitation, and sea level rise, but concedes that with regard to groundwater, “[v]ery simply, no one knows for sure, but close monitoring, planning, and responses to changes will likely be necessary.”237
In light of these conclusions, both governmental agencies and nongovernmental organizations recommend that water decision-makers operate existing water systems to allow for increased flexibility. Other recommendations include incorporating climate change research into infrastructure design, conjunctively managing surface water and groundwater supplies, and integrating water and land use practices. As implemented in the GMMP set forth in Section 4.9, close monitoring of groundwater levels in the Sonoma Volcanics and adaptive management techniques will allow for optimal decision making in the face of uncertainty. Climate change may worsen droughts, so more efficient groundwater basin management may be necessary to
230 Pacific Institute for Studies in Development, Climate Change and California Water Resources: A Survey and Summary of the Literature, prepared for the California Energy Commission, Public Interest Energy Research Program (July 2003), republished in California Water Plan Update (2005), at 20 (“Pacific Institute Survey”) [http://www.waterplan.water.ca.gov/docs/cwpu2005/vol4/vol4-globalclimate-climatechangeandcaliforniawater.pdf]. 231 California Department of Water Resources, Managing an Uncertain Future: Climate Change Adaptation Strategies for California’s Water, at 23 (October 2008) [http://www.water.ca.gov/climatechange/docs/Climate- ChangeWhitePaper.pdf]. 232 Pacific Institute Survey. 233 Id. 234 Id. 235 Id. 236 Water Replenishment District of Southern California, Will Climate Change Affect Groundwater in the Central and West Coast Basins?, Technical Bulletin Volume 10 (Winter 2007) [http://www.wrd.org/engineering/reports/- TB10_Winter_2007_Climate_Change.pdf]. 237 Id. at 2.
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avoid overdraft and to take advantage of opportunities to store water underground. Because the Sonoma Volcanics aquifer is not a coastal aquifer, it will not be subject to seawater intrusion.
In summary, while climate change is likely to have some impact on groundwater supplies underlying the Project site on a long-term basis, the direction and magnitude of that impact is unknown to the scientific community. Compared to surface water supplies, groundwater is likely to be more reliable in the face of climate change. The Sonoma Volcanics aquifer in particular contains a large quantity of water and is actively recharged on a regional scale at a rate much greater than proposed extractions to serve the Project. Thus, there is no evidence to suggest that climate change will adversely affect the reliability of local groundwater supplies for the Project.
4.11 Reliability Assessment
Due to the nature of groundwater, it is a highly reliable source of water. Groundwater is stored in aquifers, which act as natural long-term storage reservoirs, making water available year-round and during both wet and dry hydrological conditions. As described above, groundwater in the Suscol area has not been identified by DWR as being in an overdraft condition, where withdrawals are greater than recharge on a long-term basis. Reliability is increased due to the regional nature of the Sonoma Volcanics aquifer, which is evidenced by the area of recharge, direction of groundwater flow, confining clay layer, artesian condition, and historical water level recovery following decreased groundwater extractions at the Project site.238 As discussed above, the long-term available groundwater supply of the aquifer underlying the Project site is at least 3,100 AFY, which is almost double the projected water demands of the Project and other groundwater users.
Therefore, the Project’s reliance on the Sonoma Volcanics aquifer is reasonable, and groundwater underlying the Project site has a high likelihood of being available for the first 20 years of the Project and beyond. If groundwater resources underlying the Project site were to become subject to greater use pressures, the Project would be well-positioned to preserve its use of groundwater based on paramount overlying rights. In the event that rights in and to the Sonoma Volcanics aquifer in the Suscol area are ever adjudicated in a court, overlying rights will be granted a priority over non-overlying users. Generally, established water right users—users with established and demonstrated reasonable and beneficial use of water—will be protected in the event of an adjudication that fixes the rights of all parties. In addition, Stetson has concluded that groundwater extractions off-site are unlikely to have any significant impact on the availability of groundwater for the Project.239 Accordingly, the entire analysis for this WSA demonstrates the sufficiency of groundwater from the basin to meet the projected water demand associated with the Project.
Currently, NRP plans to provide the water purveyor with at least two wells located on the Project site and with a collective production capacity sufficient to meet all Project water demands on a sustained basis.
238 Id. at 6-1, 6-2. 239 Id. at 4-6, 4-7, 6-1, 6-2. 68 AUGUST 25, 2011
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There are a number of factors that lead to the conclusion that the groundwater resources of the Sonoma Volcanics aquifer in the Suscol area will be sufficient to meet the potable water demands of the Project over a 20-year planning horizon, in normal, single dry and multiple dry years.
• Groundwater has been extracted from the Sonoma Volcanics aquifer underlying the Project site since the early 1900s without negative impacts on groundwater levels or other users.
• Historical data indicate that as much as 1,230 AFY of groundwater was produced from the Project site, which is approximately double the groundwater production required for the Project.240
• From 1989 through 2005, groundwater production at the Project site averaged approximately 150 AFY, and groundwater levels remained artesian and approximately at the ground surface.241
• The Sonoma Volcanics aquifer in the Suscol area received subsurface inflow from the north at a rate of at least 2,700 AFY, and direct recharge from the east at a rate of at least 400 AFY, for a combined supply of at least 3,100 AFY. Both of these sources are dependent on long-term multi-year trends rather than short term hydrologic conditions.242
• Projected groundwater pumping from all landowners and users in the Suscol area (including existing uses, the Project and anticipated future uses by others) equals approximately 1,660 AFY, which is less than 55 percent of the total annual recharge rate.243
• The impact of groundwater production at the Project site on the closest other groundwater user would be at most 1.2 feet, which is insignificant and will not cause any lack of available groundwater.244
• The hydrogeology of the MST area varies from that of the Suscol area because of the different sources of recharge, smaller degree of confinement of the Sonoma Volcanics in some areas and historical overpumping of the MST area, none of which affect the Suscol area.245
• Increased groundwater extractions for the Project are projected to lower groundwater levels in the Smith Brown Well No. 1 between 1.0 and 2.0 feet. That well is located south of the boundary of the MST area, and such an impact on groundwater levels would not be significant. Cumulative groundwater extractions for the Project and all other
240 Id. at 6-1. 241 Id. 242 Id. at 6-2, 6-3. 243 Id. at 6-3. 244 Id. at 4-6. 245 Id. at 6-3.
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groundwater users in the Suscol area are projected to lower groundwater levels in that well of at most 3.1 feet.246
Based on these factors, local groundwater from the Sonoma Volcanics aquifer underlying the Project site is determined to be available to meet all potable water demands (620 AFY), in addition to other existing and future uses of groundwater, including agricultural and manufacturing uses. This conclusion applies for the 20-year planning horizon of this WSA, in normal, single dry and multiple dry years.
246 Id. at 6-2. 70 AUGUST 25, 2011
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SECTION 5 IMPORTED SURFACE WATER
This section of the WSA describes imported surface water supplies that may be utilized to meet all or part of potable water demands for the Project in order to reduce reliance on local groundwater supplies. All non-potable water demands will be met with recycled water.
5.1 Imported Surface Water
Currently, several urban water purveyors within Napa County, including CON and AmCan, utilize imported surface water supplies. Most of those supplies are derived from the SWP based on a contract between NCFCWD and DWR. As described in Section 7.3.3.1 of this WSA, that contract entitles NCFCWD to take delivery of SWP water supplies based on a Table A allocation, plus certain other supplies that may be available in some years, such as carryover water, Article 21 water and water from the turn-back pool. In addition, NCFCWD or the urban purveyors can acquire non-SWP water supplies for conveyance to Napa County using SWP facilities. This section of the WSA analyzes the availability of such imported, non-SWP water supplies for the Project.
There are three components to successful surface water importation for the Project: (i) source of the water, including water rights, addressed in Section 5.3 below; (ii) diversion of transferred water from the Sacramento-San Joaquin Delta via SWP facilities, addressed in Section 5.4; and (iii) conveyance of the water through SWP and local water distribution facilities to the Project site, addressed in Section 5.5.
5.2 Laws Affecting Water Right Assignment and Change
In order to implement an assignment or transfer of water from one owner, point of diversion, place of use and purpose of use to another, the parties (assignor and assignee or transferor and transferee) must follow the requirements of California law. The Mill Creek water right being evaluated in this WSA as a potential source of water for the Project is an appropriative surface water right in the Sacramento River system, as described below.
For assignments or changes involving appropriative surface water rights that were initiated prior to December 19, 1914—such as the Mill Creek right—parties must implement the assignment or change so that other water users are not injured by the change.247 No prior approval is needed from any federal, state or local regulatory agency.
The method for changing pre-1914 rights is in contrast to that for changing post-1914 rights. For assignments or transfers involving appropriative surface water rights that were initiated on or after December 19, 1914, the parties must obtain the prior approval of the State Water Resources Control Board (“SWRCB”), which must determine that the change would not result in substantial injury to any legal user of water and would not unreasonably affect fish, wildlife or other instream beneficial uses.248 A change is subject to environmental review under CEQA, and the petition to the SWRCB should include all project features or mitigation measures required to
247 CAL. WATER CODE § 1706. 248 CAL. WATER CODE §§ 1702, 1736.
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avoid significant environmental effects.249 The SWRCB process typically requires between 24 and 36 months to complete, and includes filing of a transfer petition, opportunity for protests by other water users and interested parties, submission of written and oral testimony, an evidentiary hearing, written briefing and a final, written decision by the SWRCB.250
Assignment or transfer of an appropriative water right does not require prior approval from any federal, state or local regulatory agency other than the SWRCB. There is no federal law of water resources. Additionally, state laws regarding surface water, including transfers, have preempted local regulations of the same subject matter. The only exception is that local jurisdictions may regulate surface water transfers that rely upon increased groundwater extractions. Since the proposed Mill Creek surface water supply is not being made available to the Project based on groundwater substitution, that supply would not be impacted by local regulations in Tehama County.251
5.3 The Mill Creek Water Source
The first component of successful surface water importation is source water, including water rights and the ability to implement a permanent assignment and change from existing to proposed water diversion patterns. For purposes of importation for the Project, surface water should have the following characteristics: the source of the water should be the same as for the SWP, i.e., the Sacramento River system; the source water should be of a sufficient quantity that it meets the demands of the Project, as well as potentially providing additional water supplies to meet Napa County needs; potential for the surface water to be diverted at the SWP facilities due to a cessation or reduction in use by the assignor; and the water rights involved should be relatively senior, so that they are not subject to undue restrictions in normal, single dry or multiple dry years.
This section analyzes a potential surface water supply for the Project based on the Mill Creek water right within the Sacramento River system. It concludes that the criteria above would be met by the Mill Creek water right, and that importation of Mill Creek water to the Project is feasible.
5.3.1 Background Information and Description of Water Source
Orange Cove Irrigation District is an irrigation district formed under Division 11 of the California Water Code, with a five-member governing board. OCID encompasses approximately 28,000 acres (44 square miles) in southeastern Fresno County and northwestern Tulare County. It provides retail water service to agricultural users and operates small hydroelectric facilities at Friant Dam on the San Joaquin River and on the Friant-Kern Canal immediately upstream of the Kings River Siphon Structure.
OCID possesses a pre-1914 appropriative water right outside of its service area on Mill Creek, a tributary to the Sacramento River. As shown on Figure 4 , Mill Creek, formerly known as Los
249 CAL. PUB. RES. CODE § 21002. 250 See 23 CODE OF CAL. REGS. §§ 648 et seq. 251 For local regulations, see TEHAMA COUNTY CHARTER, Art. VI, §§ 1, 2 (limiting off-parcel use of groundwater); TEHAMA COUNTY CODE, Ch. 9.40 (requiring permit for off-parcel use or sale of groundwater, and limiting radius of influence for groundwater extraction wells). 72 AUGUST 25, 2011
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Molinos Creek,252 joins the main stem of the Sacramento River in Tehama County south of the Red Bluff Diversion Dam. The main stem of Mill Creek is approximately 58 miles in length from its spring sources in Lassen Volcanic National Park to its confluence with the Sacramento River.
Prior to December 19, 1914, a Californian could form an appropriative right to the use of surface water by simply diverting water and placing it to beneficial use.253 No statewide administrative registration or permitting system existed like the one managed by the SWRCB today. Common historical materials that are useful for establishing pre-1914 rights include testimony of witnesses (although there are few witnesses alive in 2011 who can testify to events prior to 1914), records of testimony in prior court cases or other proceedings, maps, photographs, records of water diversions or use, records of crops grown through irrigation, deeds to water rights for which consideration was paid and any other reliable materials. Because the Los Molinos Colony built up around Mill Creek was a “planned development” of its day, there is a rich, documented history of land and water use dating back to subdivisions for agricultural use based on maps filed between 1907 and 1914.
OCID’s pre-1914 water right originated as a diversion and appropriation from Mill Creek that can be traced back to Joseph Cone, a significant wheat farmer in the region. The right was developed by continuous beneficial use since prior to 1914 by Mary Runyon, a successor to Joseph Cone, who later allocated portions of her adjudicated pre-1914 rights to a group of individuals, including John Patrick and Wood Orchards. OCID acquired its interest in the water right from successors in interest of Patrick and Wood.
In 1868, Joseph Cone purchased portions of an original Mexican land grant known as the 1844 Dye Land Grant, through which Mill Creek flows. In 1882, Cone purchased additional land, known as the Toomes Estate, lying north of Mill Creek.254 Cone was not satisfied that the acreage he had accumulated by 1882 was sufficient for growing wheat. Early in 1884 he purchased two additional parcels of land from the owners of Rancho Molinos, lying south of Mill Creek. These parcels of land became known as the 10,000-acre Cone Ranch.
At the time, Rancho Molinos was owned by Isabella Butler. When Cone purchased Rancho Molinos, he granted Mrs. Butler the right to the use of a ditch through his new lands to bring water from Mill Creek to her remaining property south of the portions just sold. A year later Isabella Butler and Cone signed an agreement defining the exact amount of water that was to come through the ditch.255 The amount was 218 miner’s inches, and notation was made that the
252 For clarity, this Supplement consistently refers to the waterway as Mill Creek, even during periods of time when the historical records use the name Los Molinos Creek. 253 See Utt v. Frey, 106 Cal. 392, 395 (1895); Nevada County & Sacramento Canal Co. v. Kidd, 37 Cal. 282, 311 (1869). See also Wells Hutchins, The California Law of Water Rights, at 88 (1956). 254 Margaret Bauer, History of the Los Molinos Land Company and of Early Los Molinos, at 14 (1970). This history report was prepared as a thesis while the author was a student. 255 Id. at 14.
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Figure 4. Mill Creek General Location
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water right was to go with the land. For years the ditch was known as the Butler Ditch, and was so designated on some of the older maps.256
By the turn of the century, the Cone family and the Cone/Ward Company owned vast acres of land, extending north from Mill Creek to the southern banks of Antelope Creek (the next watershed north) and south to the north side of Deer Creek (the next watershed south) and into the foothills. The Sierra Lumber Company acquired most forested lands within the upper Antelope Creek watershed and the Central Pacific Railroad Company owned forested lands in the upper watersheds of Mill and Deer Creeks. Extensive water diversion projects which included diversion dams, canals and flumes were constructed at this time to bring water to the valley floor for agricultural purposes, subdivisions and towns.257 There are three diversion dams on Mill Creek. Two are operated by Los Molinos Mutual Water Company (“LMMWC”) and one by the Clough and Owens ranches.
Cone also purchased various sections of public land adjacent to his property. The first group of these parcels lay along Mill Creek to the east of the Toomes grant line, thus further protecting Cone’s interest in the waters of the creek. The second group lay along the eastern boundary of the same grant where it approached the Dye Grant, thus straightening out the boundary line and including the base of the foothills.258 When Cone died in 1894, the property was split amongst five family members, and various portions were eventually acquired by the Los Molinos Colony (later the Los Molinos Land Company) and Mary Runyon, one of Mr. Cone’s daughters.259 Mary Runyon acquired 2,643 acres of the Cone Ranch, including appurtenant water and ditch rights.
In the fall of 1906, the Los Molinos Land Company decided to form a subsidiary water company, the Coneland Water Company. This water company would contract with the Land Company for water on the entire project, which could be divided among the tracts as they were put on the market. Contracts already issued to settlers could then be cancelled and new ones substituted under the new company. This water company was in existence until it was reorganized into a mutual water company—LMMWC—in 1948.260 LMMWC is the current owner of water rights related to the Los Molinos Colony, is the most significant diverter from Mill Creek and serves as the court-appointed Watermaster for the stream.
Before any considerable amount of irrigation was undertaken and when water supplies appeared to be abundant, the flow of water into diversion ditches was not as carefully measured as later became necessary. In his report to the Los Molinos Land Company in 1911 on the distribution of the Cone lands, Harold Wheeler, Mary Runyon’s property manager, made an effort to estimate the actual amounts of water to which Mary Cone Runyon and others were entitled.261 Such an estimate was vital because the Mill ditch had prior diversion rights to all others when it came to the waters of Mill Creek. The Los Molinos Land Company conducted extensive studies
256 Id. at 15. 257 Id. at 15, 22. 258 Id. at 15, 22. 259 Id. at 23-24. 260 Id. at 60. 261 Id. at 21.
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on the rights to Mill Creek, and the Los Molinos Land Company eventually went to court to quantify the rights to the water of Mill Creek.262
Although Mary Cone Runyon was not associated with the Land Company at any time, the water rights which came to her through her father’s estate affected the progress of the Land Company. She had received an undivided four-fifths interest in the so-called Runyon Ditch and in the water which it carried, to be used on her lands south of Mill Creek, plus the other half of the “remaining waters” which she shared with her sister.263 To further complicate the situation, before 1905 she had already conveyed parts of her property to the E. Clemens Horst Company and to W. E. Gerber with water and ditch rights commensurate with their holdings.264 It was 1917 before a final settlement of all claims and interests in Mill Creek could be achieved, and it required court action to accomplish it in 1920, as discussed further below.
5.3.1.1 Adjudication Decree
The Runyon water right was adjudicated in an August 16, 1920 court decree in the case of Los Molinos Land Company v. Cloughs, Tehama County Superior Court, Action No. 3811 (“Decree”), after the Los Molinos Land Company, a predecessor of the LMMWC, sued the other water users, including Mary Cone Runyon, in an attempt to settle the water rights on Mill Creek and use of the Runyon ditch. The court undertook an intensive study of the claims and reached a decision in 1920. Pursuant to this Decree, the Runyon right was allocated 13 percent of the water flowing past the point of diversion, junior to certain prior adjudicated rights, in flows of up to 203 cubic feet per second (“cfs”).265 The Decree does not make any adjudication with regard to any rights to water which may be flowing at any time in excess of 203 cfs.266 Accordingly, other parties conceivably may obtain a right beyond those adjudicated in the Decree when the flows in Mill Creek are more than 203 cfs. A copy of the Decree is attached as Exhibit I.
Under the Decree, the rights overlap with all riparian rights claims of the various parties. Under Article VII of the Decree, the quantities to which the parties are entitled under the Decree “include whatever quantities of water such parties are entitled to divert from said river by virtue of owning land riparian thereto.” Thus, the Decree fixes riparian rights on Mill Creek and creates a level of certainty that is not available for most streams in California. Although the OCID rights are appropriative in character and not riparian, this provision provides greater certainty to the OCID rights because it obviates any riparian rights from being considered paramount. As further stated in Article VII, “Except as herein expressly declared, no priority of right in respect to the waters of said river exists as between said parties, the right of each of them in respect to said water being on a parity with the rights of all of the others of said parties, and all of them being entitled to exercise simultaneously and continuously their several rights as herein defined.” Thus, OCID currently possesses the right to a continuous percentage of the flow of Mill Creek, and that right is not subject to the priority of other rights and is only subject to restriction based on natural variability in the flows of Mill Creek, which are discussed in Section 5.3.3.
262 Id. at 21. 263 Id. at 51. 264 Id. at 51. 265 Decree, at § II. 266 Id. 76 AUGUST 25, 2011
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According to the terms of the Decree, each of the parties “is and will be at all times entitled to use or dispose of the share allotted to such party of the water of said river in any manner, at any place, or for any purpose which such party may desire in accordance with whatever agreement or arrangement such party may make with any other person or corporation.”267 Thus, the decree recognized the transferability of the OCID water right and the fact that the assignee of the right can change the place and purpose of use as a matter of right, without needing the approval of any entity.
The Decree also appointed Los Molinos Land Company (now LMMWC) to be the Watermaster of the Los Molinos River and the Runyon Ditch charged with ditch maintenance and delivery of water to all who were entitled to it.268 As Watermaster, LMMWC is to make the apportionments of water under the terms of the original Decree. It controls any and all diversions of water from the river by ditches and canals, and all parties and their successors to the Decree are required to comply with any and all reasonable rules and regulations of the Watermaster that relate to the distribution of the water among canals and ditches.269 LMMWC continues to exercise its authority as Watermaster over water allocations in Mill Creek.
Figure 5 and Figure 6 depict the facilities that are in place to divert and convey water pursuant to the OCID water right.270 The historical and current point of diversion from Mill Creek is the Runyon Dam on Mill Creek in Tehama County, in the vicinity of the unincorporated community of Los Molinos. The Runyon Dam is located approximately 2.5 miles upstream from the confluence of Mill Creek and the Sacramento River and is equipped with a ladder for fish passage and a fish screen that prevents fish from entering the Runyon Ditch. From the Runyon Dam, water is diverted through the Runyon Ditch on the south bank of Mill Creek to a number of properties, including the Wood Orchard property on which the OCID water right was previously used. The Buena Vista Ditch is a spur off the Runyon Ditch and delivers water to lands including the Patrick property on which the OCID right was also previously used. All of these facilities are operated by LMMWC for the benefit of its shareholders and other parties with rights on Mill Creek.
In addition to the Runyon Dam and Ditch facilities, LMMWC owns and operates larger diversion facilities on the north bank of Mill Creek. Those facilities are used exclusively by LMMWC and are not connected to the OCID water right, except insofar as LMMWC coordinates the operation of all diversions from Mill Creek in its capacity as Watermaster.
5.3.1.2 OCID Purchase of Right
The Runyon right was allocated among successor owners such that 2.07 percent of the net flow of Mill Creek came to be owned by John A. Patrick, and 3.5 percent of the net flow of Mill Creek came to be owned by Wood Orchard, who subsequently transferred the entire Wood Orchard portion of the Runyon right to Tim Smith. Pursuant to separate sale agreements
267 Id. at § VII. 268 Id. at §§ X, XIV. 269 Id. at §§ X, XIV. 270 The Runyon Dam and Ditch photographs were taken on October 27, 2010 and depict the current condition of the water diversion facilities.
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Figure 5. Mill Creek Water Diversion and Conveyance Facilities
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Figure 6. Photos of Runyon Dam and Ditch
Runyon Diversion Dam Runyon Ditch Fish Screen
Upper Runyon Ditch Lower Runyon Ditch
Former Wood Orchard Property Former Patrick Property
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executed on October 19, 2000 with John A. Patrick and Tim Smith and the related recorded deeds, OCID became the owner of the Patrick and Wood Orchard portions of the Runyon right, together aggregating 5.57 percent of the designated net flow in Mill Creek. The remaining percentage of the original 13 percent Runyon right allocation is in the possession of various parties other than OCID.
Pursuant to the Decree, the OCID right is not limited to seasonal diversion, and water can be diverted year-round.271 Since the initial diversion by Joseph Cone in the late 1800s through its acquisition by OCID, the Runyon water right was continuously put to beneficial use for agricultural irrigation on the Patrick and Wood Orchard properties. When OCID acquired the water right in 2000, the right was separated from the Patrick and Wood Orchard lands, which had converted to use of groundwater based on the water quality needed to irrigate walnuts with sprinklers. Since 2000, the OCID water right has been put to use by various parties on the Mill Creek ditch system pursuant to a Water Transfer License between OCID and LMMWC acting as the Watermaster dated April 1, 2005, as discussed further below.
5.3.1.3 Mill Creek Conservation/Restoration Effort
OCID originally acquired the water right with the intent to dedicate the water to a specific environmental restoration project, in part to offset OCID’s restoration charges under its Central Valley Project service contract, pursuant to the Central Valley Project Improvement Act of 1992. The concept was that by making an investment to support a conservation and restoration effort to protect spring run salmon habitat, OCID would benefit fish and demonstrate benefits to the restoration program. OCID intended to dedicate water arising under its right to support the proposed Mill Creek Anadromous Fish Adaptive Management Plan. By late 2009, the project was not approved by the U.S. Bureau of Reclamation, and thus OCID determined to sell the water right as unnecessary to its future operations.
5.3.1.4 Water Transfer License with Mutual Water Company
During the period of OCID’s ownership, the water arising under the right has been put to continuous beneficial use for agricultural irrigation, substantiated in the records of OCID and LMMWC acting as the Mill Creek Watermaster. Recent beneficial use has been pursuant to a Water Transfer License between OCID and the Watermaster, dated April 1, 2005. OCID may at any time terminate the license agreement and direct the use of its Mill Creek rights elsewhere.
The 2005 Water Transfer License states that LMMWC and OCID are jointly responsible for allocable shares of Watermaster costs, routine operations and maintenance expenses and capital expenses on various sections of the Runyon and Buena Vista Ditches. OCID states that it is desirous of effecting a transfer of its water supply to LMMWC, yet LMMWC is “willing to accept the water and to relinquish all right, title and interest to any flows of said water upon due
271 The Decree states at section VII: “Each of said parties is and will be at all times entitled to take and divert from said river the quantity of water herein and hereby allotted to such party at such point or points on said river as such party may see fit, and by such means as such party may see fit to adopt…. Except as herein expressly declared, no priority of right in respect to the waters of said river exists as between said parties, the right of each of them in respect to said water being on a parity with the rights of all of the others of said parties, and all of them being entitled to exercise simultaneously and continuously their several rights as herein defined.” 80 AUGUST 25, 2011
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notice from OCID.”272 In exchange for providing water to LMMWC, LMMWC will pay OCID’s costs of Watermaster. If OCID decides to provide LMMWC with notice that it intends to revoke or suspend the license, OCID must pay the normal costs of Watermaster.273
5.3.2 Option Agreement
On December 15, 2010, NRP and OCID entered into an Option and Agreement for Assignment of Water Right (“Agreement”), pursuant to which OCID granted NRP an option to purchase 2.00 percent of the 5.57 percent water right currently owned by OCID. (That percentage would equal a maximum of 3.8 cfs out of the first 203 cfs of Mill Creek flows.) According to the Agreement, “[n]o further grant, instrument, deed or agreement shall be necessary to make the Option effective.” The option may be exercised by NRP in its discretion for use at the Project or any other location. Upon NRP exercising the option and paying the purchase price, OCID will deed the water right to NRP or its designee, which might be the water purveyor for the Project or a local agency such as NCFCWD, CON or AmCan.
Under the Agreement, NRP is responsible for conducting environmental review for the assignment and change of the water right from OCID to the Project. NRP is conducting that environmental review through this WSA and the preparation of the EIR to which this WSA is attached. In addition, NRP is responsible for arranging all conveyance of the water supplies to the Project site. Such conveyance is described in Section 5.5.
The parties to the Agreement recognize that exercise of the water right will need to be implemented by LMMWC acting as the Watermaster for Mill Creek. LMMWC does not have discretion to deny the assignment or change of the water right, but because LMMWC has significant water rights of its own on Mill Creek, there may be opportunities to enhance the reliability of the assigned water right for purposes of the Project by working with LMMWC on the timing of diversions. NRP and OCID have agreed to jointly work with LMMWC to seek optimal diversions from Mill Creek for the benefit of the Project, OCID’s retained water right and the water operations of LMMWC.
5.3.3 Mill Creek Water Resources
The Almanor Ranger District in Lassen National Forest prepared a Watershed Analysis report for Mill Creek in 1999. Appendix H of the report examined stream discharge. The report characterized the geomorphic, ecologic and hydrologic context of the Mill Creek watershed, and identified uses in the watershed.274 The watershed is relatively long and narrow, with moderate to steep slopes. Extended low gradient channel types are uncommon on the mainstems, restricted to Upper Mill Creek and reaches in the valley floor near the Sacramento River.275 Steep slopes adjacent to the main channels served as historic barriers to human activity, and recent land use allocations have protected these areas such that the main stem near stream environments are essentially undisturbed.276
272 2005 Water Transfer License, at 1. 273 2005 Water Transfer License, Art. 5. 274 Almanor Ranger District, Watershed Analysis for Mill, Deer, and Antelope Creeks, at 1 (1999). 275 Id. at 3. 276 Id. at 3.
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The headwaters of Mill Creek, located in Lassen Volcanic National Park, cut through an ancient andesitic stratocone (layered andesitic lavas and pyroclastic deposits that were erupted at 600- 400 ka). The hydrothermal system associated with this ancient volcano has altered the more permeable pyroclastic rocks in the center of it to mostly clay. This has locally enhanced runoff by glacial and fluvial processes. Morgan and Growler Hot Springs are located along Mill and Canyon Creeks just north of Highway 36. The last additional geothermal input into Mill Creek occurs just north of the town of Mill Creek. These springs have a seasonal and diurnal variation but contribute about 10 to 15 percent of the stream flow.277
Appendix H of the report reviewed stream discharge historically. Discharge was measured from September 1909 to September 1913 and has been measured on a daily basis by the USGS since October 1928 at USGS Site 11381500 MILL C NR LOS MOLINOS CA, which is located at about 5 miles above the mouth and 5 miles northeast of Los Molinos. Discharge was also measured from 1929-1932 and 1985-1988 at the Highway 36 bridge about 10 miles east of Mineral. The majority of annual large flow events occur in December, January and February when snow could be expected to be present in the transient snow zone (above about 3,000 feet in elevation).278 Earlier flow peaks in September through November are most likely rain events with little snow influence. Later peaks (mid- March through May) indicate snowmelt-generated peaks. Evidence of rain and snow events is also provided by the period of record maximum events for each watershed.279
Mean monthly flows over the period of record display a pattern of wet December to March periods. Mill Creek has both high elevations and a large percentage of its watershed in high elevation (snow zone). This is reflected in high flows during the typical snow melt period of April through June. Mill Creek produces total flows on average of 215,000 AFY.280 The peak discharge on Mill Creek, with more than twice the discharge of the second largest (December 1964) storm, occurred on December 11, 1937.281 This storm was far above the gauge height (maximum at that time of 14,000 cfs), and was first calculated by USGS at 23,000 cfs. This estimate was later revised to 36,400 cfs.282 This is an enormous flow relative to the size of the watershed and stream channel, especially when compared to the Decree which allocates only the first 203 cfs of stream flow.
Regarding low flows, four periods of low precipitation over the period of record stand out. These are periods when there were at least two consecutive years when precipitation was less than 60 percent of the long-term average. These periods are: 1916-19, 1924-25, 1976-77, and 1990-92.283 Overall, the Watershed Analysis report concluded that there is sufficient water available to satisfy all currently existing diversions on Mill Creek.
277 Id. at A-2. 278 Id. at H-2. 279 Id. at H-2. 280 Id. at H-4. 281 Id. at H-4. 282 Id. at H-4. 283 Id. at H-5. 82 AUGUST 25, 2011
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5.3.4 Mill Creek Biological Resources
Mill Creek, along with Antelope and Deer Creeks to the north and south, is of great importance for anadromous fisheries in California, including spring and fall run chinook salmon (Oncorhynchus tshawytscha) and steelhead (Onchorhynchus mykiss). It is believed that the spring-run chinook salmon in the three watersheds may be the last remaining wild populations in the Central Valley. The whole length of Mill Creek is usable as habitat. Although there are water diversions from the three creeks, there are no major impoundments or barriers to fish passage, which is very rare in the Sacramento River tributaries. The anadromous fish habitats on the creeks are probably the best remaining habitats in the Central Valley and serve as important anchors for species health. Studies have found that protection, maintenance and improvement of this habitat is essential to conserving wild anadromous fish stocks considered “at-risk” of extinction.284
Historically, water diversions had the potential to dewater the lower reaches of Mill Creek.285 Instream or downstream transfers of water provide a benefit to fisheries preservation efforts by allowing the relevant quantity of water to remain in and support base stream flows in Mill Creek and the Sacramento River. The Watershed Analysis report recognized this benefit by observing that prior studies of water diversions in lower Mill Creek—which include the OCID right— “have consistently identified limited flows in the reaches as one factor limiting anadromous fish production in the watersheds.”286 This would especially be true since the migration of spring-run chinook salmon on lower Mill Creek is typically between April 15 and June 30 of each year, during the normal irrigation season.287
The stakeholders on Mill Creek, including the U.S. Forest Service (“USFS”), California Department of Fish and Game (“DFG”), DWR, Mill Creek Conservancy (“Conservancy”) and LMMWC, have worked to develop a long-term strategy to manage Mill Creek since approximately 1990. The Conservancy is an organization formed in 1994 to represent the interests of certain local landowners and water right holders in that effort.
The U.S. Forest Service adopted a long term strategy for management of aquatic habitats within the watershed of Mill Creek. Elements of the strategy are: restoration; riparian habitat conservation areas; monitoring; collaboration; and watershed conservation practices.288 One recommendation is for “[m]aintaining and restoring in-stream flows such that riparian, aquatic and wetland habitats are sustained, and patterns of sediment, nutrient and wood routing and channel dynamics are sufficient to sustain aquatic and riparian species.”289 The proposed change of part of the OCID water right to use at the Project would further than recommendation by providing additional flows in lower Mill Creek downstream of Runyon Dam.
In 1920, the Tehama County Superior Court of the State of California adjudicated entitlements to all Mill Creek flow below 203 cubic feet per second (cfs). As such, water right holders on Mill Creek legally divert a significant portion of the surface water flow for agricultural beneficial use.
284 Id. at 4, 11, 14, E-1. 285 Id. at E-5, E-6. 286 Id. at 22. 287 Id. at E-3. 288 Id. at 28. 289 Id. at 33.
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During certain times of the year, especially during dry or critically dry years, the agricultural demand for surface water can reduce Mill Creek flow and expose in-stream barriers to fish migration.290 Fishery experts recognize Mill Creek as a high priority stream for the protection and enhancement of Chinook salmon spawning habitat.291 Mill Creek surface water diverters currently participate in a long-term cooperative management plan to help provide sufficient flow for fish migration while also maintaining irrigation supplies and the recognition of surface water rights.
5.3.4.1 Instream Flow Requirements for Fish Passage
In July of 2009, DFG, in cooperation with the Conservancy and LMMWC, prepared a report as part of its Upper Sacramento River Salmon and Steelhead Assessment Project, entitled, Surface Flow Criteria for Salmon Passage Lower Mill Creek Watershed Restoration Project.292 A four- year salmon passage study was completed on Mill Creek to refine minimum instream flow requirements to successfully transport adult Chinook salmon upstream of water diversion points in dry water years. Habitat parameters for unimpaired passage based on real-time instream flow, water temperature and channel passage conditions was established based on fish observations during pulsed flow events and fish counts during upstream migration.293
The Conservancy was awarded a grant by USBR to implement a Lower Mill Creek Watershed Restoration Program. The objective of this Program is to develop and implement a plan for the improvement and restoration of fishery habitat on the lower reach of Mill Creek by addressing the following four components:
• Investigate and develop a long term Water Management Plan; • Complete an irrigation system efficiency assessment; • Investigate the potential for additional conjunctive use by characterizing existing groundwater resources; and • Develop and test surface flow criteria for unimpaired passage of salmonids.
DFG’s Anadromous Fish Monitoring Component of the Lower Mill Creek Watershed Restoration project satisfies the fourth component of this Program. Salmonids present in Mill Creek that benefit from this program include: upstream migrating adult spring- and fall-run Chinook salmon and steelhead, and downstream migrating juvenile Chinook and steelhead.294 The study reported that flows of 34 cfs and a minimum passage depth of 0.4 ft could potentially transport adult salmon with careful monitoring and selective riffle modifications.295 A study design was developed to determine the following:
• Minimum surface flow for unimpaired passage over critical riffles for all life stages of salmonids;
290 California Department of Water Resources, Lower Mill Creek Watershed Project, Conjunctive Use Study at 1 (November 2008) (“Conjunctive Use Study”). 291 Conjunctive Use Study at 1. 292 California Department of Fish and Game, Surface Flow Criteria for Salmon Passage Lower Mill Creek Watershed Restoration Project at 4 (July 2009). 293 Id. 294 Id. at 4-5. 295 Id. at 5. 84 AUGUST 25, 2011
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• The timing and duration of spring pulse flows and fall flow releases to trigger fish migration; • Upper water temperature thresholds to signal the end of seasonal salmon migrations.296
The study concluded that hallow riffles upstream of Highway 99 were always passable, without modification, once conditions in the lower 0.6 miles of creek had improved either by flow augmentation or riffle modification.297 Beaver dams and dammed swimming holes are annual occurrences that could impede salmon migration. Each spring, when flow drops below 100 cfs and in the fall as instream flow is released back into Mill Creek, a walking survey needs to be completed from Runyon Dam to the Sacramento River. In addition to measuring water depth at low flow riffles and preparing for riffle modification, beaver dams and swimming holes will be manually breached to allow for fish passage.298
The most critical passage area in Mill Creek is the lower 0.6 miles of creek, i.e., starting approximately 2 miles downstream from Runyon Dam. Two transverse riffles in this lower reach require manual excavation in dry water years to provide passage for adult Chinook salmon. One critical riffle consistently was the shallowest and widest riffle in lower Mill Creek. Wetted widths ranged from 108 ft to 226 ft when flows ranged between 33 cfs and 106 cfs, respectively. Without riffle modification, even at flows near 100 cfs, riffle depths may cause fish stranding.299
Two geologists from DWR were invited to the mouth of Mill Creek to assess the current conditions and describe the creek dynamics influencing the confluence of the creek and the formation of the long transverse riffles. Their recommendation was to assess lower Mill Creek on an annual basis and commit to minor riffle modifications for fish passage.300 DFG noted that since the creek is heavily influenced by the management of Sacramento River flows, major riffle modification or channel reconfiguring would be counter-productive.301 DFG concluded that the following set of riffle modification criteria was necessary for unimpaired adult salmon passage (the larger depth was chosen to avoid potential stranding in longer corridors):
• Width: At least 12 feet wide • Depth: At least 6.7 inches deep • Length: Position the excavated channel in the shortest reach that can maintain average velocities of 2.2 ft/sec.302
DFG noted, “If time and labor permit, excavations should be made deeper to allow for reductions in flow and provide sufficient passage for [salmon runs].”303
The pattern of water discharge in Mill Creek has a clear effect on spring Chinook run timing, as each mode of passage appears to occur during a period if increasing daily discharge.304 Almost
296 Id. at 5-6. 297 Id. at 10. 298 Id. 299 Id. at 11. 300 Id. 301 Id. 302 Id. at 12. 303 Id. 304 Id. at 14.
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all natural increases in discharge during spring months (May 1 through June 15) coincide with increases in Chinook passage. The intent of pulse flows initiated by increasing irrigation bypass is to mimic this natural daily discharge and attract later arriving spring run Chinook into Mill Creek. For DFG’s spring pulse flows, “the pulse did not attract additional adult salmon into Mill Creek.”305 The pulse flow did not have a measurable effect on water temperatures.
The most successful component of DFG’s fish passage study in determining minimum bypass flows to effectively pass fish was the incremental addition of water in the fall to a dry creek channel.306 Each fall from October 15 through November 30, from 2005 through 2008, DFG requested LMMWC to incrementally release bypass flows. Flows were requested once the maximum daily water temperature dropped below the 57°F threshold for successful spawning. Adult salmon migration monitoring in 2006 thru 2008 showed that 99 percent of salmon migration into Mill Creek occurs by the time instantaneous water temperatures reach 67°F.307 Ultimately, DFG concluded that “in the future, additional refinement needs to be made with the timing of pulse flows… When minimum daily water temperatures, measured at the MCH gage, exceed 66 of for a multi-day period, then it is presumed migration is over for the season. If the juvenile salmonids are also not encountered at the rotary screw trap, bypass flows for adult spring migrating salmon can be terminated.”308
The United States Fish and Wildlife Service (“USFWS”) prepared a restoration plan for Central Valley anadromous fish dated January 9, 2001, entitled Restoration Plan for Anadromous Fish Restoration Plan. The Anadromous Fish Restoration Program (“AFRP”) was created pursuant to section 3406(b)(1) of the Central Valley Project Improvement Act of 1992 and directs the United States Secretary of the Interior to develop and implement a program to double the natural production of anadromous fish, such as salmon and steelhead, in Central Valley streams. The AFRP prioritizes contributions to natural production, improving species status, restoring natural habitat values, modifying CVP operations and implementing supporting measures. Listing Mill Creek as a “high priority,” USFWS identified four actions that would directly benefit anadromous fish on Mill Creek:
• Action 1: Continue to provide instream flows in the valley reach of Mill Creek to facilitate the passage of adult and juvenile spring-, fall- and late-fall-run chinook salmon and steelhead. • Action 2: Preserve the habitat productivity of Mill Creek through cooperative watershed management and development of a watershed strategy. • Action 3: Improve spawning habitats in lower Mill Creek for fall-run chinook salmon. • Action 4: Establish, restore, and maintain riparian habitat along the lower reaches of Mill Creek.309
Although the plan listed the above actions to implement the plan, the details on accomplishing each action item were not elaborated upon in the USFWS document.
305 Id. 306 Id. at 16. 307 Id. at 13. 308 Id. at 18. 309 U.S. Fish and Wildlife Service, Restoration Plan for Anadromous Fish Restoration Plan at 53 (January 9, 2001). 86 AUGUST 25, 2011
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5.3.4.2 Increasing Lower Mill Creek Flows
Since 1990, DFG, DWR, and LMMWC have participated in various programs designed to increase instream flows during critical fish migration periods, while maintaining agricultural supplies and surface water rights.310 As part of these efforts, Mill Creek water users participate in voluntary water lease and groundwater exchange programs designed to increase instream flows during critical spring and fall fish migration periods.311 Along with other entities, DWR in 2008 conducted a study to help establish methods of monitoring and studying fish passage, assessing agricultural water use efficiency and examining the potential for additional use of groundwater, as opposed to use of surface water diversions, in the lower Mill Creek watershed. Data currently on file with DWR, along with published and unpublished reports, contributed to the majority of information provided in the 2008 report. DWR also used data it collected and analyzed as part of the 2003 Tehama County Water Inventory and Analysis, which was conducted in cooperation with Camp Dresser & McKee, Inc. under the direction of the Tehama County Flood Control and Water Conservation District.312
Reviewing the geology and hydrology of Mill Creek and surrounding areas, DWR concluded that the potential for conjunctive use in the lower Mill Creek watershed area is high. “The Tuscan Formation has sufficient groundwater in storage in this area to allow for additional groundwater extraction while maintaining long-term sustainability. LMMWC should be able to use groundwater substitution to supplement surface water supplies during dry or below normal water years, while in-lieu recharge should be used for aquifer recovery during normal, wet, or above normal water years.”313 While the Conjunctive Use Study did not specifically address the effects of a conjunctive use program on Chinook salmon spawning habitat, the report concluded that any loss of surface water supplies may be substituted with groundwater.314
After several earlier short-term agreements, LMMWC, DWR, DFG and the Conservancy entered into a 2007 Agreement for the Implementation of a Long-Term Cooperative Management Plan for Mill Creek (“Implementation Agreement”). The parties formed a managing body (“Management Committee”) for the implementation of a long-term cooperative management plan for Mill Creek in a joint effort to provide spring flows (May 1 through June 15) and fall flows (October 15 through November 30) for spring- and fall-run Chinook salmon, respectively.315
As recited in the Implementation Agreement, “Upper Mill Creek currently provides sufficient habitat for spring-run Chinook Salmon holding, spawning, and early life stage development. Augmenting instream flows at certain times will result in improved passage, however, which may benefit migrating juvenile and adult salmon during late spring months (May 1 through June 15). During the Spring, low flows may cause in-stream barriers, particularly in dry and critically dry years.”316 In addition, improved passage may also benefit migrating adult fall-run Chinook
310 California Department of Fish and Game, Surface Flow Criteria for Salmon Passage Lower Mill Creek Watershed Restoration Project (July 2009), p.4. (“Surface Flow Criteria”). 311 Conjunctive Use Study, at 1. 312 Id. 313 Id. at 29. 314 Id. 315 Implementation Agreement, at 1. 316 Id. at Recital D.
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salmon from October 15 through November 30 when low flows may cause in-stream barriers.317 The Implementation Agreement expressly protected the free exercise of all water rights on Mill Creek.318
There are two basic mechanisms by which instream flows may be increased for fishery protection purposes in lower Mill Creek under the Implementation Agreement. Together, these mechanisms are called the Mill Creek Water Exchange Program (“MCWEP”). First, one or more parties may enter into “water use agreements,” under which DFG will lease or permanently purchase water rights on Mill Creek for the purpose of enhancing instream flows.319 Such agreements must be voluntary arrangements between the parties. Second, DFG may “call” on Mill Creek flows through groundwater substitution. DWR has drilled wells within the LMMWC service area that can extract groundwater for discharge into the LMMWC distribution canals. If additional flows are needed to meet minimum instream flow requirements for salmon or steelhead passage, DFG may call for LMMWC to reduce its diversions in exchange for groundwater pumped from the DWR wells. DFG is responsible for establishing the times and amounts of water that are desirable to remain in lower Mill Creek for salmon flows during the spring and fall.320 The Parties are not required to provide or forego Mill Creek surface water for salmon flows beyond the amount of instantaneous flow from groundwater sources available for replacement irrigation water.321
5.3.4.3 Impact of the Project on Instream Flows
As proposed, the assignment and change of the OCID water right for the supply of imported surface water to the Project would consist of several elements: a change in the point of diversion from Runyon Dam on Mill Creek to Barker Slough Pumping Plant in Barker Slough, downstream from the original point of diversion; change in the place of use from the Patrick and Wood Orchard parcels and LMMWC service area to the Project site in Napa County; and change in the purpose of use from irrigation to municipal and industrial use. Water that would be available from the OCID water right would not be diverted from Mill Creek at Runyon Dam, but would be allowed to flow down lower Mill Creek to the Sacramento River, thence the Delta and Barker Slough. As a physical matter, the assignment and change of the water right would mean less diversions at Runyon Dam, more water in Mill Creek, the Sacramento River, the Delta and Barker Slough, and more diversions from Barker Slough Pumping Plant. More information on the diversion of water at Barker Slough is described in Section 5.4.
As described in Section 5.3.4.1, lower Mill Creek is considered to be critical habitat for spring and fall-run chinook salmon and steelhead. The resource agencies (DFG, USFWS) have determined several actions that would be important to preserving or enhancing Mill Creek’s value as habitat. These actions include monitoring, altering the streambed for improved fish passage, and increasing instream flows. Section 5.3.4.2 describes efforts of those agencies and local stakeholders to increase streamflows in lower Mill Creek, culminating in the MCWEP. The primary goal of that program is to increase streamflows in lower Mill Creek during the
317 Id. 318 Id. at Recital A. 319 Id. at § II.E. 320 Id. (12) 321 Id. (12) 88 AUGUST 25, 2011
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spring (May 1 through June 15) and fall (October 15 through November 30), particularly during dry or critically dry years.
The proposed assignment and change of the OCID water right for the benefit of the Project will have incidental benefits to salmon and steelhead habitat on lower Mill Creek generally and the MCWEP specifically. The Project would result in increased flows in Mill Creek, as water available under the OCID water right is allowed to flow past Runyon Dam to the Sacramento River. The water right would provide valuable instream flows, as it would constitute approximately 3.8 cfs or 11 percent of the 34 cfs needed for successful passage of adult salmon down lower Mill Creek. The water would be available during the critical periods of May 1 through June 15 and October 15 through November 30, as well as other times during the year. The water would be available for instream flows during all hydrologic year types, including dry and critically dry years when it would be particularly beneficial for maintaining instream flows.
The Project imported surface water supplies would directly benefit the MCWEP because it would provide water to DFG and DWR without requiring LMMWC or other water right holders on Mill Creek to reduce any of their water right diversions for irrigation purposes. The parties to the Implementation Agreement agreed to work together to find financial resources to fund the MCWEP, and the Project would be helpful by supplying instream flows at no cost to those parties, preserving their financial resources to take additional actions. The proposed assignment of water rights from OCID to the Project is consistent with the voluntary approach of the MCWEP and its express goal of respecting water rights on Mill Creek. There is no aspect of the Project that would be inconsistent with the MCWEP or other actions on Mill Creek to enhance salmon and steelhead habitat.
5.3.5 Yield of the NRP Water Right
The amount of water yielded by the OCID water right varies, due to the fact that OCID is allocated a percentage of the designated net flow in Mill Creek, which changes on a daily basis, although flows exceed 203 cfs on many days. Based on review of USGS daily data, the average yield for the 2.00 percent of the OCID right that would be assigned to NRP for the Project was 2,163 AFY during the period from 1929 through 2009. The minimum annual yield was recorded in 1977, at 1,338 AFY, and the maximum annual yield was recorded in 1983 at 2,636 AFY. The annual historical yields of the water right are shown in Figure 7 and listed in Table 14.
While the average yield of the water right is 2,163 AFY, for purposes of water supply planning a better measure is the yield which is exceeded in a given percentage of years. As seen in Figure 8, the yield curve for the Mill Creek water right is relatively flat, meaning that it may be characterized as highly reliable.322 The median yield of the water right is 2,226 acre-feet (“AF”), which is higher than the average yield. There is a gentle downslope of yield through 96 percent of years (or 79 out of 81 historical years), when yield is still 1,703 AFY. The water right had a
322 By comparison, the yield curve of the SWP for agencies within Napa County declines more steeply across all years, and drops quickly after the 55th percentile to almost zero yield during the driest of years. Thus, addition of the Mill Creek water right to the existing portfolio of Napa County imported water supplies would likely increase the overall reliability of those combined supplies. See California Department of Water Resources, The State Water Project Delivery Reliability Report 2009, at 46 (August 2010) [http://baydeltaoffice.water.ca.gov/swpreliability/- Reliability2010final101210.pdf].
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Figure 7. Historical Yield of the Mill Creek Water Right
3,000
2,500
2,000
1,500 AF
1,000
500
0
7 9 6 8 35 38 74 950 953 962 965 989 992 001 1929 1932 19 19 1941 1944 194 1 1 1956 195 1 1 1968 1971 19 1977 1980 1983 198 1 1 1995 199 2 2004 2007 Historical Year
Figure 8. Exceedance Curve for the Mill Creek Water Right
3,000
2,500
2,000
1,500 AF
1,000
500
0
1% 8% 1% 5% 9% 12% 16% 20% 23% 27% 30% 34% 38% 4 45% 49% 52% 56% 60% 63% 67% 71% 74% 7 82% 85% 89% 93% 96% Percentage
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Table 14. Historical Annual Yields of the Mill Creek Water Right (AF) Year Yield Year Yield Year Yield Year Yield 1929 1,714 1950 2,272 1971 2,367 1992 1,703 1930 1,990 1951 2,277 1972 2,224 1993 2,343 1931 1,519 1952 2,442 1973 2,369 1994 1,890 1932 1,851 1953 2,407 1974 2,429 1995 2,433 1933 1,736 1954 2,322 1975 2,397 1996 2,348 1934 1,778 1955 2,068 1976 1,764 1997 2,334 1935 2,008 1956 2,355 1977 1,338 1998 2,599 1936 1,998 1957 2,222 1978 2,241 1999 2,379 1937 2,055 1958 2,358 1979 2,113 2000 2,247 1938 2,403 1959 2,017 1980 2,258 2001 2,050 1939 1,720 1960 2,118 1981 2,094 2002 2,103 1940 2,226 1961 2,094 1982 2,510 2003 2,392 1941 2,477 1962 2,252 1983 2,636 2004 2,311 1942 2,426 1963 2,260 1984 2,486 2005 2,342 1943 2,293 1964 2,055 1985 2,039 2006 2,519 1944 2,119 1965 2,354 1986 2,251 2007 2,016 1945 2,296 1966 2,137 1987 1,922 2008 2,034 1946 2,171 1967 2,313 1988 2,009 2009 1,959 1947 1,916 1968 2,277 1989 2,090 Average 2,163 1948 2,165 1969 2,383 1990 1,852 Minimum 1,338 1949 1,803 1970 2,370 1991 1,768 Maximum 2,636 Data Source: Daily stream flow records from USGS. lower yield in the two historical years of 1931 (1,519 AF) and 1977 (1,338 AF), although such lower yield is present in only less than 4 percent of all years over a long historical record. In the recent three-year drought from 2007 through 2009, the lowest yield would have been 1,959 AF in 2009.
Overall, this analysis demonstrates that the Mill Creek water right is highly reliable. The water right can meet all potable water demands of the Project (620 AFY) in all years, with a minimum of 1,338 AFY and average of 2,163 AFY. Without considering the availability of conveyance losses (which is discussed in Section 5.4.6) or infrastructure capacity (which is discussed in Section 5.5), the Mill Creek water right would provide the Project with an average excess supply of 1,543 AFY and a minimum of 718 AFY.
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5.3.6 Approach to Making Water Available
In order to make water available for the Project, OCID would notify LMMWC that the Water Transfer License agreement of April 1, 2005 is terminated for 2.00 percent of its 5.57 percent water right. As provided in that agreement, LMMWC is required to “relinquish all right, title and interest to any flows of said water upon due notice from OCID.”323 LMMWC would reduce its diversions into the Runyon Ditch system and allow the water to flow down lower Mill Creek into the Sacramento River. From the original point of diversion, the undiverted water would flow down the Sacramento River into the Delta to be diverted at Barker Slough.
OCID is entitled to assign or sell the water right to any person pursuant to Section VII of the Decree, which provides that:
Each of said parties is and will be at all times entitled to use or dispose of the share allotted to such party of the water of said river in any manner, at any place, or for any purpose which such party may desire, or in accordance with whatever agreement or arrangement such party may make with any other person or corporation.
Section VII makes clear that a party, such as OCID, may dispose of its water rights in its own discretion, without the need for any approval from any third party on Mill Creek. This is consistent with the history of ownership of the OCID water right, since as discussed in Section 5.3.1, the water right has been owned by several parties over the years, before it was purchased by OCID.
Although NRP holds the option to purchase the Mill Creek water right from OCID, NRP would assign the water right to an entity in Napa County for future use at the Project. The water right would most likely be assigned to NCFCWD for the benefit of the Project water purveyor, but depending on the institutional arrangement, the assignment might also include the local entity conveying imported surface water to the Project site, i.e., the City of American Canyon or City of Napa.
Any excess imported surface water above the needs of the Project could be used for multiple purposes in Napa County, including deliveries to the City of St. Helena (which would allow that city to reduce its groundwater withdrawals from the Napa Valley Subbasin) or the MST area (to provide supplemental water supplies to that area of localized groundwater stress). NRP intends that Project water supplies, including water yielded from the surface water right on Mill Creek, will be used for the limited purposes of: (i) providing water to the Project; (ii) providing water to Napa County water purveyors as replacement for water supplies that are currently available to those purveyors, but are less reliable or more expensive than imported surface water supplies yielded from Mill Creek; or (iii) providing water to Napa County water purveyors as replacement for groundwater supplies. Furthermore, NRP intends that water supplies yielded from the water right will not be used to support development of previously undeveloped lands, and it is on that basis that NRP would assign the Mill Creek water right to a Napa County water purveyor.
323 2005 Water Transfer License, at 1. 92 AUGUST 25, 2011
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Since the original place of use for the OCID water right was converted to walnut production and groundwater irrigation because of water quality approximately 10 years ago, there would be no need for additional actions to be taken to make water available for the Project. LMMWC would have less water available for its operations, but that company has never established any permanent entitlement to the OCID water rights; it only enjoyed a license that was terminable at any time. Thus, LMMWC members have not planted additional acreage or permanent crops based on access to the inherently uncertain OCID water rights.
A large percentage of the lands irrigated by LMMWC currently are in pasturage, e.g., 49 percent in 2004,324 and although LMMWC members may have enjoyed fewer restrictions on their water use since 2005 as a result of temporarily using the OCID water rights, common irrigation practices for pastures allow a wide range of applied water without significant differences in pasture conditions. For example, in DWR’s drought water transfer programs for 2009, 2010 and 2011, pastures “are not eligible for idling or shifting transfers because it [is] too difficult to determine the real water savings from a lack of authoritative ETAW values, substantial variability in cultural practices, and other crop specific reasons.”325 Similarly, the reduction in water use within the LMMWC service area based on the assignment and change of 2.00 percent of the OCID water right for the Project would be “difficult to determine” at most.
The impact of reduced diversions by LMMWC would never be greater than 2 percent of Mill Creek diversions, since the Project water right would be set at that amount during periods of low flow. In an average year, the Project would reduce diversions in Los Molinos by 2,163 AF, compared to LMMWC’s average right to about 79,300 AF and total streamflow of 215,000 AF. Given total diversions by LMMWC, the lack of identifiable lands that would be impacted, the indeterminate impact of reduced water supplies for pasturage lands and the temporary nature of LMMWC’s license to use the OCID water right, there would not be any identifiable impact on water supplies within the Los Molinos area as a result of the assignment and change of 2.00 percent of the OCID water right for the Project. This would also mean there would not be an identifiable impact on local agriculture or the local economy.
The same conclusion is true for riparian habitat within the LMMWC service area, particularly along its irrigation canals and ditches. LMMWC would not cease conveyance of water through any irrigation canals as a result of the assignment and change of the OCID water right to the Project. The only historical canal that would be dry following the assignment of the OCID water rights to the Project would be the lower Runyon Ditch, but that canal was abandoned as a result of the shift to groundwater on the Patrick and Wood Orchard parcels in the late 1990s, and not as a result of the Project. While less water would flow through the remaining LMMWC canals, the relatively small percentage reduction described above would not be expected to cause any measurable impact to riparian habitat.
324 See Irrigation Training and Research Center, Los Molinos Mutual Water Company Modernization Recommendations – Final Report at Tables A3, A4 (February 2008). 325 California Department of Water Resources, DRAFT Technical Information for Water Transfers in 2010, Information to Parties Interested In Making Water Available for 2010 Water Transfers, at 12 (November 2009) [http://www.water.ca.gov/drought/docs/TransferTechInfo-110609.pdf]. See also California Department of Water Resources, DRAFT Technical Information for Water Transfers in 2011, Information to Parties Interested In Making Water Available for 2011 Water Transfers, at 14-15 (January 2011) [http://www.water.ca.gov/drought/docs/- TechInfoDoc-WaterTransfers-2011.pdf].
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The Mill Creek Decree constitutes the final determination of all water rights on the Mill Creek stream system. As provided in Section XVIII:
From and after the entry of this decree each and every one of the parties to this action, and each and every person claiming or to claim under any such party, and each and every employee, agent or successor in interest of such party, is hereby perpetually enjoined and restrained from ever at any time taking or attempting to take or divert from said [Mill Creek] any quantity of water in excess of the share or quantity of water allotted to such party by this decree, or from asserting any right or claim in respect to the waters of said river … inconsistent with the provisions of this decree, or from interfering with or obstructing any other party to this action in the exercise of any right herein or hereby declared, established or adjudged.
Accordingly, other parties with water rights on Mill Creek do not have a legal basis for claiming they would be injured by the proposed assignment to the Project. The relative rights of all the water users on Mill Creek have already been evaluated and determined by the superior court in the Decree, and no party may seek to re-litigate those claims. As long as the Mill Creek water right proposed for the Project is used within its definition under the Decree (which is defined by a percentage of flow, and can be used “in any manner, at any place, or for any purpose”), it cannot be held to injure another water used on Mill Creek. As an adjudicated right, the water right that would be acquired by NRP is considered legally secure.
The next question is whether an assignment and change of the OCID water right would injure any water user on the Sacramento River downstream from the confluence with Mill Creek. Because the assignment and change would increase flows in the Sacramento River, there is no manner in which a water user on the Sacramento River or in the Delta could be injured. This includes both individual water right holders and contractors of the CVP and SWP.
5.3.7 Other Sources of Water
In addition to the water that is available from the OCID water right that would be permanently acquired for the Project, NRP or the retail water purveyor for the Project could acquire other water rights from the Sacramento River system for temporary transfer to the Project. Such transfers could be used to increase imported water supplies in the driest 4 percent of years that were identified in Section 5.3.5.
There is a functioning market for water rights in the Sacramento River system, with rights being purchased and sold on feasible economic terms on a regular basis, especially for temporary (less than one year) periods. Vested water rights currently are available for purchase on the Sacramento River, if NRP decided to pursue the acquisition of additional supplies over one or more years. Examples of recent transactions in the Sacramento River system include:
• Temporary transfers from several water right holders, including South Sutter Water District, Garden Highway Mutual Water Company, Tule Basin Farms, City of Sacramento and Sacramento Suburban Water District, to a group of SWP contractors,
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including Antelope Valley-East Kern Water Agency, Dudley Ridge Water District, Kern County Water Agency, Metropolitan Water District of Southern California, Napa County Flood Control and Water Conservation District, Oak Flat Water District, Palmdale Water District, and San Bernardino Valley Municipal Water District for a total of up to 23,699 acre-feet during 2010.326
• Temporary transfers from numerous water right holders to DWR in 2009 pursuant to the 2009 Drought Water Bank program, for a total of up to 52,773 acre-feet.327
• Permanent transfer in 2010 from several water right holders to the Woodland-Davis Clean Water Agency as part of the Woodland-Davis Water Supply Project.328
• Permanent transfer from Natomas Central Mutual Water Company to South Folsom Properties, LLC of between 8,000 and 15,000 AFY, pursuant to a 2007 agreement, for purposes of meeting the demands of a development project.
In the past few years, there have been a greater number of transfers of water on the Sacramento River system than are listed above, such that temporary transfers have become largely routine. A transfer of water from vested, historically exercised rights on the Sacramento River system to the Project would be subject to the same conditions as the water rights change described above, i.e., it could not cause injury to any legal user of water or have an unreasonable effect on fish, wildlife or instream beneficial uses. Based on historical practices, it is expected that a transfer could be arranged that would meet those conditions and gain SWRCB approval, such as the transfers described above. Although such water sources would each have their own respective points of diversion, places and use and purposes of use, transfers of such sources would all be substantially similar in that they would all derive from the Sacramento River system, they would all be diverted at the same new point of diversion for SWP facilities, subject to the same legal and physical restrictions, and have the same off-site environmental impacts. Any on-site environmental impacts would need to be identified at the time and would be subject to the requirements of CEQA, if applicable.329
326 See In the Matter Of License 11118 (Application 14804) Petition for Temporary Change Involving the Transfer of up to 10,000 Acre-Feet of Water from the South Sutter Water District to Eight State Water Contractor Agencies, SWRCB Order 2010-0022-DWR (July 1, 2010); In the Matter Of License 2033 (Application 1699) Petition for Temporary Change Involving the Transfer of up to 5,802 Acre-Feet of Water from the Garden Highway Mutual Water Company to Eight State Water Contractor Agencies, SWRCB Order 2010-0023-DWR (July 2, 2010); In the Matter Of License 2840 (Application 10030) Petition for Temporary Change Involving the Transfer of up to 3,520 Acre-Feet of Water from Tule Basin Farms to Eight State Water Contractor Agencies, SWRCB Order 2010-0024- DWR (July 2, 2010); In the Matter Of Permit 11360 (Application 12622) Petition for Temporary Change Involving the Transfer of up to 4,377 Acre-Feet of Water from the City of Sacramento and Sacramento Suburban Water District to Eight State Water Contractor Agencies, SWRCB Order 2010-0025-DWR (July 2, 2010). 327 See SWRCB Orders 2009-0038-DWR, 2009-0040-DWR, 2009-0041-DWR, 2009-0042-DWR, 2009-0043- DWR, 2009-0044-DWR, 2009-0045-DWR, 2009-0046-DWR, 2009-0047-DWR, 2009-0048-DWR, 2009-0053- DWR, 2009-0054-DWR and 2009-0055-DWR [all online at http://www.waterboards.ca.gov/waterrights/water_- issues/programs/applications/transfers_tu_orders/]. 328 See Woodland-Davis Clean Water Agency Website [http://www.wdcwa.com/documents]. 329 Note that temporary water transfers are typically exempt from CEQA. See CAL. WATER CODE § 1729.
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5.4 Diversion of Water at SWP Facilities
5.4.1 Introduction to the Delta
The Delta is located at the confluence of the Sacramento, Cosumnes, Mokelumne, Calaveras and San Joaquin Rivers, just before the combined rivers flow into Suisun Bay, leading to San Francisco Bay and the Pacific Ocean. The Delta watershed occupies more than 40 percent of the land area of California. The Delta itself consists of several hundred miles of interconnected waterways, separated by levees and islands. A map depicting the Delta is shown in Figure 9.
Water flows in the Delta are tidal, so that the brackish water/freshwater interface flows outward toward Suisun Bay and inward toward the river sources on a diurnal basis. Water flows through Delta channels in changing patterns based principally upon inflows from the Sacramento and San Joaquin Rivers, tidal inflows and outflows, and water pumping in the Delta region. Water enters the Delta from the Sacramento River at Freeport, just south of Sacramento, and from the San Joaquin River at Vernalis.330 The Sacramento River contributes between 77 and 85 percent of freshwater inflows to the Delta, the San Joaquin River contributes between 10 and 15 percent, and the combined flows of the Cosumnes, Mokelumne and Calaveras Rivers contribute most of the remainder. Total Delta inflows average 21 million AFY, with a range between 6 and 70 million AFY. Dry and critical dry year Delta inflows average about 12 million AFY.331
The Delta is at the core of California’s two main water distribution systems—the federal Central Valley Project (“CVP”) and the SWP. The Delta provides water to more than 25 million people, including more than 500,000 people who live in the Delta, an area which spans five counties (Sacramento, San Joaquin, Contra Costa, Yolo and Solano), 27 cities and two ports. The Delta supports more than 300,000 acres of in-Delta agriculture, as well as four million irrigated agricultural acres throughout California.
5.4.2 Delta Water Infrastructure and Barker Slough Diversions
Both the CVP and SWP utilize the Delta as an integral part of their water supply systems. Both systems store water in upstream reservoirs, e.g., Lake Shasta for the CVP and Lake Oroville for the SWP, release stored water into the natural channels that are tributary to the Delta, and pump the water out of the southern Delta for delivery to federal and state contractors in central and southern California. Since 1951, the CVP has owned and operated the C.W. “Bill” Jones Pumping Plant (formerly known as the Tracy Pumping Plant) with a maximum capacity of 4,600 cfs. As part of the SWP, DWR has owned and operated the Harvey O. Banks Pumping Plant with a maximum capacity of 10,300 cfs since 1968. Both facilities are shown in Figure 9.
In addition to the large diversion pumps at the Jones and Banks pumping plants, there exist other water diversions in the Delta. The SWP operates the Barker Slough Pumping Plant in the northern Delta, as shown in Figure 9 under the name of North Bay Pumping Station, with a capacity of 140 cfs. That pumping plant is the headworks for the North Bay Aqueduct (“NBA”)
330 See CAL. WATER CODE § 12220 (defining the Delta for purposes of the State Water Resources Development System). 331 CALFED Bay-Delta Program, Final Programmatic Environmental Impact Statement/Environmental Impact Report (July 2000) [http://calwater.ca.gov/calfed/library/Archive_EIS.html]. 96 AUGUST 25, 2011
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Figure 9. Sacramento-San Joaquin Delta Area Map
Source: City of Davis, Davis-Woodland Water Supply Project Draft Environmental Impact Report, State Clearinghouse No. 2006042175 (April 2007).
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that delivers water to Napa and Solano Counties. The Contra Costa Water District operates two diversions originating in the southern Delta from Rock Slough and the Old River. There are numerous smaller public and private water diversions from the Delta for agricultural, residential and recreational purposes.
In order to convey water from the point of diversion of the Mill Creek water right described in Section 5.3 to Barker Slough, the Project would rely on natural flows of Mill Creek, the Sacramento River and the Delta. Such use of natural channels for conveyance of water is authorized by state law.332 The transferred water would be diverted from the Delta at the Barker Slough Pumping Plant and would originate predominantly from the Sacramento River, although there are local runoff flows from Yolo Bypass and from various creeks that drain into the Cache Slough complex during certain periods. Sutter Slough diverts about 25 percent of the Sacramento River flow, and most of this water flows down Sutter Slough into Miner Slough and to Cache Slough, near the downstream end of the Sacramento Deep Water Ship Channel (“DWSC”). Cache Slough connects with the Sacramento River downstream at Rio Vista. The SWP diverts water at Barker Slough which originated on the Feather River and then was released down the Sacramento River via the same pathway. The diversions for the Project would be identical to those of existing SWP operations.333
Upstream, i.e., flood tide, flow in Cache Slough moves into five channels: Miner Slough, the DWSC, Prospect Slough, Cache Slough and Lindsey Slough. Barker Slough is located upstream on Lindsey Slough. The tidal exchange into these five channels is quite large, especially since 1998 when Liberty Island (about 5,000 acres between Prospect Slough and Cache Slough) flooded when the levees breached during high winter flood flows.
Figure 10 shows the simulated tidal flows and calculated tidal volumes for Lindsey Slough (and Barker Slough) just upstream of Cache Slough for a representative month of tidal cycles (March 2001). These tidal flows were simulated with the DWR Delta Simulation Model Version 2 (“DSM2”). The tidal flows in Lindsey Slough are shown in the top panel of Figure 10. The upstream tidal flows vary during the month between spring (maximum) tides with about -4,000 cfs and neap (minimum) tides with about -3,000 cfs. The bottom panel of Figure 10 shows the tidal flow volumes, moving downstream (positive volume) during ebb tide and upstream (negative) during flood tide. The Delta tide cycle is characterized as semi-diurnal with a higher- high tide followed by a lower-low tide, and then an intermediate lower-high followed by the higher-low tide. The flood tide volumes are more uniform, while the ebb tide volumes are more unequal. The simulated upstream flood tide “exchange” volume is about 600 to 800 AF, occurring about twice each day.
The average flood tide also can be approximated by the upstream water surface area times the tidal range of about 3 feet. The simulated tidal flows shown in Figure 10 are about 1 mile upstream from Cache Slough. The average tidal flow for all of Lindsey and Barker Sloughs can
332 See CAL. WATER CODE §§ 7044, 7075. 333 California Department of Water Resources, Management of the California State Water Project, Bulletin 132-07, at 4 (2008) [http://www.water.ca.gov/swpao/docs/bulletin/07/Bulletin132-07.pdf]; California Department of Water Resources, Management of the California State Water Project, Appendix E: 2002 Water Operations in the Sacramento-San Joaquin Delta, Bulletin 132-03, at 42 (2005) [http://www.water.ca.gov/swpao/docs/bulletin/03/- Appendix_E.pdf]. 98 AUGUST 25, 2011
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Figure 10. DSM2-Simulated Tidal Flows (cfs) and Tidal Volumes (AF) for Lindsey Slough Upstream of Cache Slough for March 2001
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be estimated from the surface area of about 300 acres. The average tidal exchange would be about 900 AF, occurring twice each day. The upstream channel volume (estimated from the DSM2 model geometry) is about 3,500 AF at low tide (0 feet msl), so the tidal volume exchange is about 25 percent of the minimum volume. These tidal exchange flows occur twice each day and dominate the water movement in Lindsey and Barker Sloughs. The cumulative effects of the maximum Barker Slough Pumping Plant diversion of 140 cfs, or 275 AF per day, is about 15 percent of the total water exchange volume into Lindsey Slough of about 1,800 AF each day.
In order to implement the water transfer for the Project, DWR will need to pump a maximum of 714,600 gallons per day (peak day demand), which equals 2.2 AF per day at a rate of approximately 1.1 cfs. The incremental effects of pumping 1.1 cfs (2.2 AF) per day for the proposed water transfer will be very small (roughly 0.12 percent) compared to the normal tidal exchange of water into Lindsey Slough.
The potential effects of this additional pumping on water supplies in Barker Slough will not result in substantial injury to any legal user of water. In the case of water supplies from Mill Creek, the water will not be diverted at the original point of diversion, but will be allowed to flow down Mill Creek, the Sacramento River into the Delta and to Barker Slough before being diverted. Mill Creek, the Sacramento River and Delta waterways leading to Barker Slough will not be dewatered in any reach that could have a negative impact on the availability of water for other legal users of water; rather, those water users would have a generally positive impact on the availability of water to satisfy their rights (albeit extremely small and insignificant other than on Mill Creek).
The additional pumping also will not unreasonably affect fish, wildlife or other instream beneficial uses, since the transferred water will remain in Mill Creek, the Sacramento River and Delta waterways downstream of the original point of diversion. Allowing the water to remain in these stream reaches for an additional distance below the original point of diversion will have an insignificant, yet positive, impact on fish, wildlife and other instream beneficial uses. The impact on fish from increased pumping at the Barker Slough Pumping Plant is analyzed in the following sections of this WSA, with the same conclusion that the proposed transfer would not have an adverse impact. In addition, the impacts of the proposed change on environmental resources will be analyzed in the environmental impact report being prepared for the Project.
5.4.3 General Condition of the Delta and Various Threats
Due to use of Delta waterways for conveyance of water in the SWP system to the NBA and for a potential imported surface water supply for the Project, this section discusses the general condition and threats to use of the Delta for water supply purposes.
5.4.3.1 Endangered and Threatened Species
Many fish species reside in or pass through the Delta. Currently, six species that are affected by the Delta are listed under the federal and state Endangered Species Acts (“ESAs”): winter-run and spring-run Chinook salmon, delta smelt, North American green sturgeon, Central Valley steelhead and southern resident orca whales. Recent decline in the population of these species has led to wide-spread concern that the Delta is facing a crisis. Several species, including delta smelt, are at their lowest recorded population levels in over 40 years of recordkeeping.
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According to the theory of some scientists and environmental advocates, the present fish crisis originated in the large water projects that diverted more and more water from the rivers, culminating in the completion of Oroville Dam as part of the SWP in 1967. The diked channels of the Delta have been treated as canals to convey water to Central Valley’s agriculture and to southern and central California and Bay Area cities. In response, estuary-dependent fish such as delta smelt, longfin smelt and striped bass declined, while freshwater lake species such as largemouth bass, bluegill and catfish increased. Other theories propounded by scientists and water management agencies are that the present fish crisis was caused by growing discharges of ammonia from the Sacramento Regional Wastewater Treatment Plant, the invasion of non-native species into the Delta ecosystem and a general decline in food sources for the endangered fish species.
Regardless of the cause of these deteriorating conditions, federal agencies have issued multiple biological opinions under federal and state ESAs in recent years to address the decline in abundance of the endangered fish species. In June 2004, the U.S. Bureau of Reclamation (“USBR”) issued a new joint operating plan for the SWP and the CVP, known as the “Long- Term Central Valley Project Operations Criteria and Plan” (“2004 OCAP”) that was to govern operations for the next 25 to 40 years.334 The 2004 OCAP formed the basis for long-term CVP water supply renewal contracts with a number of farmers and irrigation districts in the Central Valley. Related to the 2004 OCAP, the USFWS and National Marine Fisheries Service (“NMFS”) issued two separate biological opinions that govern operations of the SWP and the federal CVP to protect endangered species. The USFWS biological opinion addressed delta smelt, while the NMFS opinion addressed anadromous species including winter-run and spring- run Chinook salmon and Central Valley steelhead. As a result of litigation challenging those biological opinions, in July 2006 the USBR reinitiated consultation with the USFWS and NMFS with respect to the 2004 biological opinions (with the addition of the North American green sturgeon, which was listed in April 2006). The current status of each of these biological opinions and the potential impact of each on water diversions for the Project is described below.
5.4.3.2 Current USFWS Biological Opinion
A new biological assessment for the delta smelt was issued on May 16, 2008, followed by a new biological opinion from USFWS on the 2004 OCAP on December 15, 2008 (“2008 BiOp”). The 2008 BiOp concluded that “the coordinated operations of the CVP and the SWP, as proposed, are likely to jeopardize the continued existence of the delta smelt.” The BiOp also concluded that “the coordinated operations of the CVP and SWP, as proposed, are likely to adversely modify delta smelt critical habitat.” The 2008 BiOp included Reasonable and Prudent Alternatives (“RPA”) and measures it deemed necessary to minimize the effect of the proposed actions on the delta smelt. For example, the alternatives seek to reduce entrainment of pre- spawning adult delta smelt during December to March by controlling flows and to prevent direct mortality of delta smelt larvae and juveniles by entrainment by improving flow conditions in the central and southern Delta. A host of governmental and non-governmental organizations representing water users have challenged various features of the 2008 BiOp, and that litigation is
334 California Department of Water Resources, Long-Term Central Valley Project Operations Criteria and Plan, for U.S. Bureau of Reclamation (March 2004) [http://www.usbr.gov/mp/cvo/OCAP/OCAP_BA_STATE.pdf].
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continuing in federal court today.335 The court issued a ruling on December 14, 2010 that invalidated much of the 2008 BiOp, based on findings that the document failed to use best available science and that “the analyses supporting the specific flow prescriptions set forth in the RPA are fatally flawed and predominantly unsupported.”336
Although the focus of the 2008 BiOp and other fisheries studies has been on the relatively large pumps in the southern Delta, the 2008 BiOp also examined the impact of NBA operations on delta smelt. Delta smelt migrate up into the Delta during the winter months and could be entrained into Barker Slough Pumping Plant if delta smelt are present in this region.337 DWR has been monitoring delta smelt in the vicinity of Barker Slough and surrounding areas since 1995 to estimate and analyze larval delta smelt loss at the NBA due to entrainment, and to monitor the quantity and spread of larval delta smelt in the Cache Slough complex in which Barker Slough is located. Estimated annual entrainment of delta smelt at the NBA ranges from approximately 8,000 to 32,000 annually. The NBA is equipped with a fish barrier screen that was installed in Horseshoe Bend and was designed to prevent threatened and endangered fish species from being entrained in the pumps. This fish screen that was installed to protect the delta smelt larvae excluded 99.7 percent of fish from entrainment and so actual entrainment at the NBA is probably much lower.338
Additional studies were conducted during 2010 to determine how many delta smelt are entrained at the NBA annually. The 2008 BiOp reported that “it may be low so long as the screen is maintained properly. There may be years … that large numbers of delta smelt are in the Cache Slough complex and could be subject [to] entrainment at the NBA,” however “the fish screen at NBA may protect many, if not most, of the delta smelt larvae that do hatch and rear in Barker slough.”339 The 2008 BiOp concluded that during the fall there are no expected direct effects from the NBA on delta smelt because the delta smelt do not reside in Barker Slough during this period.
Based on restrictions imposed by the California Department of Fish and Game under the California Endangered Species Act (“CESA”) to protect longfin smelt, water diversions at the Barker Slough Pumping Plant are limited to a seven-day average of 50 cfs from January 15 through March 31 during dry and critically dry years in the Sacramento River system.340
335 San Luis & Delta-Mendota Water Authority et al., v. Salazar, et al., Case No. 1:09-CV-00407-OWW-DLB; State Water Contractors v. Salazar, et al., Case No. 1:09-CV-00422-OWW-GSA; Coalition for a Sustainable Delta, et al. v. United States Fish and Wildlife Service, et al., Case No. :09-CV-00480-OWW-GSA; Metropolitan Water District of Southern California v. United States Fish and Wildlife Service, et al., Case No. 1:09-CV-00631-OWW-DLB; Stewart & Jasper Orchards v. United States Fish and Wildlife Service, United States Eastern District Court, No. 1:09-CV-00892-OWW-DLB. 336 Delta Smelt Consolidated Cases, Case No. 1:09-CV-00407-OWW-DLB, “Memorandum Decision re Cross Motions for Summary Judgment (December 14, 2010). 337 U.S. Fish and Wildlife Service, Formal Endangered Species Act Consultation on the Proposed Coordinated Operations of the Central Valley Project (CVP) and State Water Project (SWP), at 170-171, 216-217, 231-232 (2008) [http://www.fws.gov/sfbaydelta/ocap/]. 338 Id. at 171. 339 Id. 340 See California Department of Water Resources, Notice of Preparation, Environmental Impact Report for the North Bay Aqueduct Alternative Intake Project, at 2 (November 2009) [http://www.water.ca.gov/pubs/planning/- nba_aip_nop__department_of_water_resources__north_bay_aqueduct__alternative_intake_project__notice_of_prep aration_/dwr_nba_aip_nop-11-24-09.pdf]; California Department of Fish and Game, California Endangered Species 102 AUGUST 25, 2011
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Diversions are typically much smaller during that period because of lower water demands in Napa and Solano Counties, so that this restriction is not expected to have a significant impact on the ability of the NBA to meet all regional water demands, including the Project.
5.4.3.3 Current NMFS Biological Opinion
On June 4, 2009, NMFS issued its current biological opinion (“2009 BiOp”) for spring-run and winter-run Chinook salmon, Central Valley and California Central Coast steelhead, North American green sturgeon and Southern Resident killer whales. The 2009 BiOp addressed the continued, coordinated operation of the CVP and the SWP and impacts on the applicable species.341 Like the 2008 BiOp from USFWS, the validity of numerous aspects of the 2009 BiOp is currently the subject of litigation in federal court.
The 2009 BiOp concluded that CVP and SWP operations in the southern Delta will jeopardize the covered species, and destroy or adversely modify critical habitat, unless significant additional restrictions are imposed on water exports. Accordingly, the 2009 BiOp contained additional restrictions on SWP and CVP operations. NMFS calculated that these restrictions will further reduce the amount of water the SWP and CVP combined will be able to export from the southern Delta by five to seven percent (about 330,000 AFY). DWR has estimated a 10 percent average water loss expected to begin in 2010, pursuant to the 2009 BiOp. The 2009 BiOp also delineated water-temperature and flow guidelines that NMFS asserted are necessary for protecting these species. The flow guidelines could mean even more reductions to SWP exports from the southern Delta. Since the SWP allocates water to contract-holders under their base Table A entitlements at a consistent rate, without regard to whether their water deliveries are from the southern Delta or NBA facilities, this restriction does affect Table A water deliveries to NCFCWD. The restriction does not, however, affect other diversions using the NBA, such as a non-SWP imported surface water supply.
The 2009 BiOp also directly examined the impact of operation of the Barker Slough Pumping Plant which diverts water from Barker Slough into the NBA for deliveries to Napa and Solano counties.342 First, the 2009 BiOp assessed salmon exposure. It reported that endangered salmon may be present “in the waterways adjacent to the Barker Slough Pumping Plant, however several years of monitoring have failed to consistently capture any salmonids during the winter delta smelt surveys (1996 to 2004) in Lindsey Slough or Barker Slough.”343 Captured Chinook salmon come from Miners Slough, a direct tributary to the Sacramento River, but no steelhead have been captured in the Barker Slough monitoring surveys between 1996 and 2004. The location of the Barker Slough Pumping Plant is “substantially removed from the expected emigrational corridors utilized by emigrating Chinook salmon and steelhead smolts in the North Delta System.” The 2009 BiOp concluded:
Act, Longfin Smelt Incidental Take Permit No. 2081-2009-001-03, at 12 (February 2009) [http://www.dfg.ca.gov/- DCBBC415-AEFD-4F61-B106-E2C042871313/FinalDownload/DownloadId-07B694824CE997620726BEB94B3- 87C8B/DCBBC415-AEFD-4F61-B106-E2C042871313/delta/data/longfinsmelt/documents/ITP-Longfin-1a.pdf]. 341 National Marine Fisheries Service, Biological Opinion and Conference Opinion on the Long-Term Operations of the Central Valley Project and State Water Project (June 4, 2009) [http://swr.nmfs.noaa.gov/ocap/NMFS_- Biological_and_Conference_Opinion_on_the_Long-Term_Operations_of_the_CVP_and_SWP.pdf]. 342 Id. at 332. 343 Id.
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There is no discernable effect to the populations of winter-run or spring-run due to the operations of the Barker Slough Pumping Facility. The infrequent presence of Chinook salmon in the monitoring surveys indicates that Chinook salmon are at low risk of entrainment. Density appears to be quite low, and those Chinook salmon that have been captured in the monitoring surveys have tended to be in the Miners Slough, a waterway to the east of the Barker Slough. If Chinook salmon were to be pulled into the vicinity of the screen pumps by the increased exports, the screens are designed to effectively prevent the entrainment of these fish.
No steelhead have been recovered during the monitoring surveys conducted for the NBA at any of the monitoring sites sampled in the region. Therefore, it would appear that steelhead are rare in the waters and very few would have the potential to be affected by the screened export pumps. The take of fish would not be sufficient to have a population effect on Central Valley Steelhead.344
Accordingly, the 2009 BiOp found that the effects of the Barker Slough Pumping Plant on the covered species, even with the predicted increases in pumping in the future, are believed to be negligible due to: (1) the small size of the winter diversion; (2) its location 7 to 10 miles upstream from Cache Slough on Barker Slough, a dead-end slough with no significant sources of inflow that does not block a migratory corridor; and (3) and because Chinook salmon or green sturgeon do not reside in habitat near the vicinity of the NBA and Barker Slough Pumping Plant.
5.4.3.4 Other Threats for the Delta and Blue Ribbon Task Force
Because the Delta islands are generally below sea level, and the Delta waterways are critical for conveyance of water through the region, levee failure poses a significant risk for use of the Delta for water diversions. The state is actively studying the risk of levee failure and potential impacts to SWP supplies and developing a plan to protect the Delta. There are several concurrent processes for resolving these challenges.
In the spring of 2006, at the recommendation of CALFED, an interagency effort that includes 23 state and federal agencies that have management or regulatory responsibility for the Delta, DWR began a two-year Delta Risk Management Study (“DRMS”) to analyze risks to the levee system. The Stage I analysis included a discussion of the region’s assets, existing problems with the system, the degree of risk that exists and the potential consequences of multiple levee failures. Stage II addressed levee risk reductions. The DRMS report was part of the Delta Vision Report submitted to the California Legislature and Governor on January 1, 2008.
Following completion of the Delta Vision Report, the panel established by Governor Schwarzenegger began studying long-term strategic solutions for the conflicts in the Delta that include assessing alterative implementing measures and management practices to implement the Delta Vision recommendations, including actions taken to prevent or mitigate levee failure. The final recommendations will include modifications to existing land uses and services in the Delta,
344 Id. at 418. 104 AUGUST 25, 2011
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and will assess governance, funding mechanisms, water resource uses and ecosystem management practices.
5.4.4 Environmental Litigation
Specific threats to SWP and CVP exports from the Delta include various lawsuits concerning the Delta environmental conditions. A significant amount of ESA litigation has been initiated involving at least three Delta fish species, including salmon, striped bass and delta smelt. In addition, six lawsuits alleging ESA violations were also filed between June and September 2009, in response to the 2009 NMFS biological opinion regarding several salmon species in the Delta. Numerous water agencies have joined in these lawsuits. As of September 2010, at least a dozen related cases involving fish and Delta pumping were working their way through federal and state courts. The various complaints have been consolidated into two cases, as follows.
o Consolidated Delta Smelt Cases: San Luis & Delta-Mendota Water Authority v. Salazar, Lead Case No. 1:09-cv-407-OWW-DLB (E.D. Cal.). A host of water agencies and water users have sued the USFWS and other federal agencies alleging that USFWS’s 2008 BiOp for the Delta smelt is arbitrary, capricious and contrary to law. More specifically, the plaintiffs allege that USFWS ignored scientific data, misapplied or inconsistently applied data, relied on speculation, arbitrarily attributed adverse effects to CVP operations that are actually linked to other stressors and failed to rationally relate the impacts of CVP operations to population level effects.
o Consolidated Salmon Cases: San Luis & Delta-Mendota Water Authority et al. v. Gary Locke et al., Case No. 1:09-CV-01053-OWW-DLB (E.D. Cal.). A group of water users and agencies, including many of the same parties who are plaintiffs in the smelt cases, have sued NMFS to challenge that agency’s 2009 BiOp on the impacts of the CVP and SWP on a number of different salmon and steelhead species, as well as the green sturgeon and southern resident orcas. The bases for the lawsuits are that NMFS failed to adequately define or analyze effects based upon a regulatory baseline, resulting in arbitrary attribution of adverse effects to project operations rather than to other stressors; failed to use the best available scientific data, and inconsistently applied data; and failed to rationally relate the impacts of project operations to population-level effects on the subject species.
These cases are not expected to impact through-Delta conveyance or pumping from the NBA, since their focus is on, and all remedial requests relate to, the large Jones and Banks pumping plants in the southern Delta.
5.4.5 Delta Planning Processes
5.4.5.1 Legislative Actions
In response to concerns over the integrity of the Delta levee system, the state significantly increased the budget for levee repairs in 2006, and a $5.4 billion natural resources bond was approved by voters in November 2006 (“Proposition 84”), which assigned additional funds for flood control in the Delta and to plan for future water supplies.
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In 2008, the California Legislature failed to reach agreement on several water bond measures. However, the decline of the Delta ecosystem and the resultant reduction in water supply triggered the enactment of five new water bills and an accompanying bond package in early November 2009. One of those bills, Senate Bill 1 (7x), was focused solely on addressing Delta issues. The bill reformed state policy in the Delta, created a new Delta governance structure, and required development of a new Delta management plan. The policy reforms are designed to connect management of all Delta resources so the sustainability of the Delta can be restored for multiple purposes including environmental protection and water supply. The bill also reformed the Delta governance structure, which included creation of the Delta Stewardship Council (“Council”), a committee tasked with overseeing the Delta and developing a wide-ranging Delta management plan by the end of 2011. Other Delta governance changes included reform of an existing Delta governance body (the Delta Protection Commission), requiring the SWRCB to appoint a Delta watermaster charged with enforcement of the SWRCB’s water rights orders regarding the Delta, and creating a new Delta Conservancy, which is tasked with carrying out projects that advance either ecosystem restoration or economic development in the Delta.
None of the new legislation authorized a peripheral canal or alternative conveyance system to move water across the Delta; instead, it added a new system of oversight by requiring the Bay Delta Conservation Plan (“BDCP”) to demonstrate to the Council that an alternate conveyance plan meets certain goals and is consistent with the comprehensive Delta management plan and existing environmental requirements. In November 2009, a motion to put an $11 billion bond proposition on the November 2010 ballot was passed in the California State Senate and the California State Assembly. California voters were to decide in early November 2010 whether to approve the Safe, Clean, and Reliable Drinking Water Supply Act of 2010, which would provide billions of dollars to build new water projects and a program to protect the aging levees. The water bond was withdrawn from the election by the Legislature, as approved by Governor Schwarzenegger, in August 2010, with the expectation that the bonds may be placed on the ballot in 2012.
5.4.5.2 Bay Delta Conservation Plan
The BDCP will allow the State Water Contractors, an association of 27 agencies who take delivery of water from the SWP and who must comply with the federal and state ESAs, to work cooperatively to attain incidental take coverage under the ESAs via a Habitat Conservation Plan (“HCP”) and a Natural Community Conservation Plan (“NCCP”) for a new cross-Delta water conveyance system. The BDCP is being developed with the leadership of the BDCP Steering Committee, and with the participation of agencies, stakeholders, the public and independent scientists. The BDCP Steering Committee includes federal and state agencies, local and regional water agencies, fish agencies, environmental organizations, and organizations representing agricultural interests. Recently, several large agricultural representatives, including Westlands Water District and the San Luis and Delta-Mendota Water Authority, have halted their participation in the BDCP Steering Committee.
Currently, the BDCP is identifying strategies to improve the overall health of the Delta and is developing environmentally-sound ways to transport fresh water through or around the Delta. The BDCP aims to establish water flows that: (1) mimic natural flows; (2) steer fish away the state and federal water pumps; and (3) restore habitat areas throughout the Delta. Under this conservation plan, state and federal water projects may be constructed and operated with a 106 AUGUST 25, 2011
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conservation-based approach that will provide funding for ecosystem restoration. The BDCP has identified several endangered species that the plan will cover and manage. The draft conservation strategy includes biological goals and objectives for approximately 50 terrestrial and aquatic endangered and threatened wildlife and plant species, and also identifies conservation measures to help in their recovery. Species considered for coverage that are relevant to water supply issues include: delta smelt, green sturgeon, longfin smelt, winter-run Chinook salmon, and spring-run Chinook salmon.
The BDCP participants have identified the Yolo Bypass and Cache Slough complex, including Barker Slough, as key wetlands restoration opportunity areas. In September 2009, the BDCP released an Aquatic Habitat Restoration Map and Draft Conservation Strategy that identified tidal marsh restoration targets within the Yolo Bypass/Cache Slough Area. Specific restoration and enhancement sites may not be identified until plan implementation. Implementation of these developing strategies are intended to support increases in delta smelt, longfin smelt and salmonid populations in the Barker Slough area. The increased presence of these listed species could result in previously unidentified pumping restrictions at the Barker Slough Pumping Plant as resource agencies attempt to balance ecosystem restoration and water supply delivery goals. Specific restrictions have not been identified at this time and would be speculative.
While officials state that no definite decisions have been made, documents under review as part of the BDCP call for a large canal that would divert up to two-thirds of Sacramento River flows depending on the time of year (up to 15,000 cfs). At this time it is unclear how the BDCP will specifically impact water operations. However, it is clear that the BDCP will propose water operations criteria that will determine how much water could be diverted from the Sacramento River via a new water conveyance facility. Currently, a range of operations is being studied that will limit the amount of water available for diversion depending on the time of the year and real- time flows. For instance, from December through April the proposed rules would require a base flow of 9,000 to 15,000 cfs in the Sacramento River before any water could be diverted at a new northern Delta point of diversion. These rules will be put in place to support the BDCP’s goals of fish recovery and the restoration of natural seasonal flows. Officials also state that the canal will likely stretch around the east side of the Delta, rather than the west side, bisecting farmland in west San Joaquin County.
Along with evaluating a range of conveyance options, the BDCP is also evaluating improvement and reinforcement of existing Delta channels and construction of other conveyance facilities. In 2000, the CALFED Record of Decision found that relocation of the NBA intake out of Barker Slough was part of a comprehensive solution to improve the Delta ecosystem because it would alleviate impacts to delta smelt and longfin smelt in the Cache Slough complex. Therefore, there is the potential for the proposed BDCP and NBA Alternate Intake Pipe facilities to be integrated. The alternative intake project is discussed in Section 5.5.1.
Release of the public review draft of the BDCP has been delayed several times, most recently from November 15, 2010 to the spring of 2011. On March 13, 2008, DWR, acting as the lead agency on the Steering Committee, issued a notice of preparation of an EIR for the BDCP. A draft of the EIR is expected to be available following release of the BDCP draft in mid-2010. The draft BDCP and EIR will include a detailed plan to build a peripheral canal. At that point, the process of applying for take permits may begin. It is expected that a final draft of the BDCP
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will be available in late 2011, and the implementing agreement and permit decisions will be finalized in late 2011.345
The BDCP is currently receiving strong support from the state and will serve as regulatory approval for the peripheral canal. However, in April 2009, two water agencies challenged the BDCP in federal district court. The case was dismissed in September 2009 as being premature and unripe.346 While no judicial review has been granted this early in the administrative process, there is no doubt that the controversial BDCP will be challenged as soon as the environmental documents are released and the plan is approved.
5.4.5.3 SWRCB Delta Flow Criteria
The Sacramento-San Joaquin Delta Reform Act of 2009347 required the SWRCB to develop new flow criteria to protect public trust resources for the Delta ecosystem. The statute further required the SWRCB to submit its flow criteria determinations to the Delta Stewardship Council within 30 days of their development. The SWRCB conducted a public process in the form of an informational proceeding, held on March 22-24, 2010, to develop the flow criteria, and released a draft Report on Development of Flow Criteria for the Sacramento-San Joaquin Delta Ecosystem on July 21, 2010, for public review and comment. On August 3, 2010, the SWRCB adopted Resolution 2010-0039 approving the final report determining new flow criteria for the Delta ecosystem necessary to protect public trust resources.348 On August 25, 2010 the executive director of the SWRCB submitted the final report to the Delta Stewardship Council.
The report concluded that restoring the Delta’s collapsing fisheries and hydrologic rhythms are “fundamentally inconsistent with continuing to move large volumes of water through the Delta for export.” (The report noted, however, that the flow criteria did not consider any balancing of public trust resource protection with public interest needs for water.) Generally, the report’s recommendations called for significantly increased flows into and through the Delta, particularly during the winter and spring months, and imposed limits on reverse flows associated with pumping by the state and federal export pumps in the southern Delta. In order to preserve the attributes of a natural variable system to which native fish species are adapted, the report specifically called for the following flow criteria (expressed as a percentages of natural or unimpaired inflows and outflows):
o 75 percent of unimpaired Delta outflow from January through June; o 75 percent of unimpaired Sacramento River inflow from November through June; and o 60 percent of unimpaired San Joaquin River inflow from February through June.
The report also called for fall outflows to maintain brackish water habitat in the Delta in wetter years and positive flows or low reverse flows in Delta channels in most years. The SWRCB also recommended measures to improve water quality and restore natural habitat, noting that protection of public trust resources “cannot be achieved solely through flows.” Other criteria set forth in the report included: increased fall Delta outflow in wet and above normal years; fall
345 See BDCP Website [http://baydeltaconservationplan.com/default.aspx]. 346 Central Delta Water Agency v. U.S. Fish and Wildlife Service, 653 F.Supp.2d 1066 (E.D.Cal. 2009). 347 See CAL. WATER CODE § 85086. 348 See SWRCB Website [http://www.waterboards.ca.gov/waterrights/water_issues/programs/bay_delta/deltaflow/- final_rpt.shtml]. 108 AUGUST 25, 2011
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pulse flows on the Sacramento and San Joaquin Rivers; and flow criteria in the Delta to help protect fish from mortality in the central and southern Delta resulting from operations of the CVP and SWP water export facilities. The report also includes determinations regarding: variability and the natural hydrograph, floodplain activation and other habitat improvements, water quality and contaminants, cold water pool management, and adaptive management.
By contrast, spring flows to the Delta in recent years have been reduced on average by more than 50 percent. The SWRCB cited “water diversions, channel configurations, reduced flows, and other effects” as the cause of the reductions and specifically points to water diversions as the main factor for reducing spring flows to the Delta. The SWRCB emphasized that the criteria are not to be interpreted as precise flow requirements for fish under current conditions, but rather they reflect the general timing and magnitude of flows under the narrow circumstances analyzed in this report.
To the extent water available for diversion at Barker Slough is derived from the Sacramento River, which is also the source for cross-Delta flows, diversions might be reduced generally in order to meet the flow criteria that calls for 75 percent of unimpaired Sacramento River inflow from November through June. In general, however, the report focuses on impacts to the central and southern Delta caused by the large CVP and SWP pumps in the south and how to address them.
5.4.5.4 Other SWRCB Processes
In 2008, the SWRCB updated its Strategic Workplan for the Delta (“Workplan”), which included a workplan for making any needed changes to water rights and water quality regulation consistent with the program of implementation. The Workplan identified beneficial uses of the Delta, water quality objectives for the reasonable protection of those beneficial uses and a program of implementation for achieving the water quality objectives. Under the Workplan, the SWRCB will initially focus on the southern Delta salinity and San Joaquin River flow objectives, and the program that implements those objectives. Following completion of the preview process for the Workplan, the SWRCB will undertake any additional water quality control planning that is identified through that process.
The Workplan requires a comprehensive review of both the Bay-Delta Plan and other implementation measures designed to establish interim and long-term water quality objectives, and to protect fish and wildlife, beneficial uses of water and the public trust. The Workplan includes information-gathering activities by the SWRCB that may affect the scope of the Bay- Delta Plan revision or provide scientific summaries to date at the commencement of the environmental review process. Those activities included an October 2008 scoping meeting on periodic review of the Bay-Delta Plan and a series of evidentiary hearings on a number of critical factual issues concerning the Delta’s ecology.
On November 18, 2008, the SWRCB voted not to proceed with an informational fact-finding proceeding as part of the periodic review of the Bay-Delta Water Quality Control Plan, as originally suggested in the Workplan. The SWRCB proceeded with its periodic review staff report. The final periodic staff report was approved by the SWRCB on August 4, 2009. The report recommended that the SWRCB conduct further review in the water quality control planning process of the following: Delta Outflow Objectives, Export/Inflow Objectives, Delta
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Cross Channel Gate Closure Objectives, Suisun Marsh Objectives, Reverse Flow Objectives, Floodplain Habitat Flow Objectives, Changes to the Monitoring and Special Studies Program, and Other Changes to the Program of Implementation. The staff report also stated that further review will be taken with regard to southern Delta salinity and San Joaquin River flow objectives, which were previously identified as issues for further review. Based on information received during the periodic review and follow-up workshops on the issues identified for additional review, SWRCB staff will develop recommendations for any needed changes to the Bay-Delta Water Quality Control Plan.
A revised draft plan was submitted in June 2009, and a second revised draft plan, along with a draft report, was submitted in October 2009. The final monitoring and evaluation plan that incorporates stakeholder comments is expected to be completed in 2010. According to the current SWRCB timeline, a draft environmental impact report is scheduled to be released for public comment in November 2010, with final completion of the process in 2011. That schedule would see the Bay-Delta Plan revisions completed in roughly the same time period as the BDCP.
5.4.6 Water Conveyance Losses
In order for the Mill Creek water right to be conveyed from its current point of diversion at Runyon Dam to the proposed point of diversion at Barker Slough Pumping Plant, the water will flow down Mill Creek and the Sacramento River to the Delta and Barker Slough. This section discusses the legal basis for such conveyance and the potential for loss of water along the conveyance route. Water conveyance losses typically occur by evaporation from the stream surface, evapotranspiration from riparian vegetation or infiltration into percolating groundwater through the bed and banks of the stream. Infiltration of surface waters into the subflow of a stream is not by itself a conveyance loss, since those waters are still part of the stream and continue to support surface water flows.349
When an appropriative right is changed, the right maintains its priority date, but the change may not injure the exercise of other water rights, even if those rights are junior.350 In the case of a change in point of diversion that moves the diversion downstream, the operative question is whether the change will cause a decrease in the amount of water available for diversion based on conveyance losses between the original and new points of diversion. If there are water conveyance losses, the changed diversion would need to be reduced by the amount of the losses, in order to prevent injury to other water right holders. If there are no water conveyance losses, the changed diversion would not need to be reduced, because there would be no injury to other water right holders. The senior water right would not be obligated to assume any pre-existing water conveyance losses of the junior rights between the original and new points of diversion, because of the strict priority system for appropriative rights.
In the case of the change of the Mill Creek water right from Runyon Dam to Barker Slough Pumping Plant, there are three relevant inquiries: (1) would infiltration of surface stream flow in lower Mill Creek during dry summer months be attributed to the change as a loss; (2) would the water right be responsible for conveyance losses along Mill Creek and the Sacramento River to
349 See CAL. WATER CODE § 1200 (defining a “stream” as “surface water, and … subterranean streams flowing through known and definite channels,” which includes subflow). 350 See CAL. WATER CODE § 1706. 110 AUGUST 25, 2011
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the Delta; and (3) would the change be responsible for Delta carriage water requirements that are imposed on certain cross-Delta water transfers? Each of these questions is addressed below.
5.4.6.1 Lower Mill Creek Alluvial Infiltration
As noted in Section 5.3.4, water diversions from Mill Creek have historically had the potential to dewater the lower reaches of Mill Creek, particularly the final 0.6 miles before it reaches the Sacramento River. While surface water flows have always been available to allow diversions at Runyon Dam, in the 2.5 miles between that structure and the Sacramento River, significant surface water flows pass into the subflow of Mill Creek. This phenomemon is partially responsible for the need for supplemental water releases for the benefit of chinook salmon and steelhead in lower Mill Creek during critical periods in the spring and fall. Typically, lower Mill Creek does not become dry on the surface until the summer months of July, August and September.
Figure 11. Geologic Map of Lower Mill Creek Area
Source: California Geological Survey.
The alluvium that contains the subflow of Mill Creek can be seen clearly in the geologic map in Figure 11. As shown in that map, as Mill Creek flows down the western slope of the Sierra Nevada Mountains onto the valley floor, it passes from overlying bedrock (Qc – Pleistocene nonmarine) to alluvium (Qf – Quaternary fan deposit). Alluvium is relatively more permeable than the bedrock and defines the subflow of Mill Creek to its confluence with the Sacramento
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River a short distance downstream. Surface waters of Mill Creek percolate into the alluvium, but continue moving within the subterranean bed and banks of the narrow valley toward the Sacramento River, where they join with the subflow of that stream.
Based on this geologic analysis, even though waters that pass Runyon Dam may percolate into the bottom of the Mill Creek stream channel, they do not leave Mill Creek, but merely become part of its subflow. Those flows are not lost to Mill Creek or the Sacramento River even though they are flowing underground. Thus, the conveyance of the Mill Creek water right from Runyon Dam to the Sacramento River would not result in a reduction of the amount available for diversion at Barker Slough due solely to infiltration of water into the alluvial subflow of Mill Creek. Percolation of subflow into the general aquifer underlying the Sacramento Valley will be addressed in the next section.
5.4.6.2 Mill Creek and Sacramento River Losses
The second question related to potential water conveyance losses is whether the water right would be responsible for conveyance losses along Mill Creek and the Sacramento River to the Delta as the result of evaporation, riparian evapotranspiration and infiltration into the general aquifer underlying the Sacramento Valley. While it would be difficult to determine the exact quantity of water conveyance losses between Runyon Dam and Barker Slough Pumping Plant, it is possible to set a range for such losses between minimum and maximum values.
Minimum losses would be zero, when considering the relative magnitude of water supplies in the Sacramento River. As explained above, the operative question is whether the change will cause water losses to increase based on the change. The proposed water right conveyance would average approximately 2,163 AFY at Runyon Dam, while the average runoff of the Sacramento River is approximately 22 million AFY.351 The water conveyance would thus represent less than 0.00002 percent of the annual runoff of the Sacramento River.
As explained above, water losses are caused by evaporation from the surface of the stream, and infiltration into groundwater underlying the stream. Marginal evaporation losses from a water right change would be based on the extent to which the change caused the stream channel to widen, and thus create additional exposure to the atmosphere to allow evaporation to occur. It is not expected that adding 2,163 AFY to a flow of 22 million AFY would have a measurable effect on the width of the Sacramento River. Therefore the water right change would not cause any marginal evaporation losses attributable to the change. The same analysis would apply to infiltration to groundwater. Surface streams infiltrate their porous beds and banks due to gravity (technically referred to as “head”), but the marginal head of the Mill Creek water right change for the Project would be incalculably small based on the relative amounts of water for the change and the pre-existing Sacramento River.
Maximum losses attributable to the change would be those losses attributed by DWR in the past to groundwater substitution based transfers of water from the Sacramento Valley. In 2009, 2010 and 2011, DWR evaluated potential water transfers from the Sacramento River that were based on groundwater substitution. In such transfers, the transferor would pump groundwater from the
351 See U.S. Geological Survey, Introduction to the Sacramento River Basin (http://pubs.usgs.gov/circ/circ1215/- introduction.htm). 112 AUGUST 25, 2011
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Sacramento Valley and use that groundwater in lieu of surface water from the Sacramento River, which the transferor would then transfer to another party for use. DWR was faced with the challenge of ensuring that these transfers did not pump groundwater that led to increased infiltration of Sacramento River water that could injure other water right holders. DWR determined that all groundwater pumping would be subject to a 12 percent reduction in order to prevent any such injury.352 That 12 percent would represent an overestimation of water conveyance losses because pumping from groundwater wells in the Sacramento Valley would induce stream flow infiltration into the underlying groundwater at a rate higher than the normal effects of hydraulic head. Thus, it is reasonable to use 12 percent as the maximum potential water conveyance losses from the change of the Mill Creek water right from Runyon Dam to Barker Slough Pumping Plant.
The exact amount of water conveyance losses attributable to the importation of surface water for the Project is likely to be determined during negotiation of a conveyance agreement with DWR, as discussed in Section 5.5.2. For purposes of this WSA, the maximum value of 12 percent is used. That approach has the result of reducing the amount of water yielded by the Mill Creek water right from an average of 2,163 AFY to an average of 1,903 AFY, rounded down to 1,900 AFY for convenience. This approach is cautious, since the actual amount of water conveyance losses are likely to be less than the maximum.
5.4.6.3 Cross-Delta Carriage Water
The third question that must be addressed related to conveyance water losses is whether the change would be responsible for Delta carriage water requirements that are imposed on certain cross-Delta water transfers. As explained in prior sections, the Delta is a complex environment that is used for substantial water deliveries for the SWP and CVP. Required Delta outflows are dependent upon a number of parameters, which include, but are not limited to, salinity levels, flow rates and export levels through the SWP and CVP in the southern Delta. The SWP and CVP place a Delta “carriage water” requirement on water transfer exports south of the Delta to ensure that exports do not violate Delta water quality standards. In its simplest form, carriage water is a fraction of discharge reserved for outflow. The carriage water requirement is essentially a water assessment, which ranges from zero to 35 percent depending on conditions at the time of the transfer. For example, if the carriage water requirement is set at 20 percent, DWR and the USBR will only allow 80 AF to be transferred through their respective projects for every 100 AF delivered to the Delta.353
The SWRCB establishes the terms under which certain points of diversion can be used by either DWR or USBR for diversions of Delta water supplies at the SWP Banks pumping plant and CVP Jones pumping plant, respectively.354 SWRCB authorization to divert at Banks and Jones pumping plants is subject to carriage water conditions: “Diversion by the USBR at Banks Pumping Plant is not authorized when the Delta is in excess conditions.”355 “Excess conditions” exist when upstream reservoir releases plus unregulated natural flow exceed Sacramento Valley inbasin
352 California Department of Water Resources, DRAFT Technical Information for Water Transfers in 2011 at 28 (January 2011) (http://www.water.ca.gov/watertransfers/docs/TechInfoDoc-WaterTransfers-2011.pdf). 353 Lower Yuba River Accord October 2007 Final EIR/EIS, 6-14. 354 See SWRCB Water Right Decision 1641 (D-1641), revised in Order WR 2000-02 (March 15, 2000). 355 Id. at 150.
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uses, plus exports.356 In contrast, “balanced conditions” exist when it is agreed by the SWP and CVP that releases from upstream reservoirs plus unregulated flow approximately equal the water supply needed to meet Sacramento Valley inbasin uses, plus exports.357 Exports are diversions of water pumped through Banks or Jones pumping plants further south.358 Export diversions and CVP and SWP carriage water are specifically excluded from the definition of inbasin entitlements under the SWRCB’s Term 91.359
DWR presently models carriage water as a function of salinity in the Delta, historical inflows and outflows from the Delta and Delta operations.360 DWR currently uses the best available Delta water quality model (DWR DSM2) to determine the carriage water impacts for each transfer on a case-by-case basis using real-time hydrologic and water quality data at the time of the transfers through the Delta that use the Banks or Jones pumping plants. The actual carriage water requirement is then assessed to water transfers as they occur.
Carriage water is defined by DWR as the “extra water needed to carry a unit of water across the delta to the pumping plants while maintaining a constant salinity.”361 Similarly, the courts have defined carriage water as “the amount of additional Delta outflow required to compensate for currents created by the export pumps.”362 Accordingly, carriage water is required as conditions of pumping transfer water south through the Banks and Jones pumping plants. Without additional pumping at those plants, there is no need to compensate with carriage water.
In sum, carriage water requirements are imposed on exports of water from the Banks and Jones pumping plants in the south Delta. Conveyance of the Mill Creek water right from Runyon Dam to the Barker Slough Pumping Plant would be upstream of these facilities, and would not affect salinity levels in the central Delta. Diversions at Barker Slough Pumping Plant are not subject to carriage water requirements. For these reasons, no conveyance water losses would be attributed to the delivery of water from Runyon Dam to the Barker Slough Pumping Plant.
5.5 Water Conveyance
5.5.1 Infrastructure
Under the proposed importation of surface water from Mill Creek in the Sacramento River system to the Project, the point of diversion for the imported water would be changed from the existing point to the intake for the NBA in Barker Slough. The NBA is part of the SWP that diverts water from the Delta for conveyance to Napa County. This section describes the NBA and the feasibility of using that pipeline for conveyance of water to the Project.
356 Id. at 150 n.79. 357 Id. at 150 n.81. 358 Id. at 150-52. 359 SWRCB Water Right Decision 1650 (D-1650) (March 1, 2011). 360 Delta Modeling Section, California Department of Water Resources, Methodology for Flow and Salinity Estimates in the Sacramento-San Joaquin Delta and Suisun Marsh, Chapter 8 – An Initial Assessment of Delta Carriage Water Requirements Using a New CALSIM Flow-Salinity Routine (http://modeling.water.ca.gov/- delta/reports/annrpt/2001/index.html). 361 Annual Report 1995: Chapter 9, Carriage Water, Delta Modeling Section Department of Water Resources Support Branch, Sacramento, CA. (http://modeling.water.ca.gov/delta/reports/annrpt/1995/chap9.html). 362 El Dorado Irrigation Dist. v. State Water Resources Control Bd., 142 Cal.App.4th 937, 951 (2006) 114 AUGUST 25, 2011
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The NBA starts at Barker Slough and delivers water into Napa County at Jamieson Canyon. Water is pumped from the Delta at Barker Slough Pumping Plant, which consists of nine pumps with a total capacity of 154 cubic feet per second (“cfs”). Original plans called for 10 pumps with a capacity of approximately 228 cfs, but only nine have been installed to date.
From Barker Slough Pumping Plant, Reach 1 of the NBA conveys water to the Travis Surge Tank located nine miles to the west. Water then flows by gravity through Reach 2 of the NBA to Cordelia Forebay. Although Reaches 1 and 2 were intended to carry 175 cfs, design of the pipeline and growth of a biofilm on the inside of the pipeline has reduced the flow to approximately 140 cfs. The 140 cfs capacity of Reaches 1 and 2 is the limiting factor for conveyance of water through the NBA. The capacity of later reaches and the combined surface water treatment plants of CON and AmCan exceed that figure. For purposes of analyzing conveyance capacity available for importation of additional water supplies for the Project, 140 cfs is the key limitation.
All SWP facilities are owned and operated by DWR for the benefit of the SWP contractors, which means that NBA capacity is effectively shared between NCFCWD and Solano County Water Agency. The SWP supply contracts between DWR and NCFCWD, and between DWR and Solano County Water Agency, do not limit each agency’s use of NBA capacity; however, for purposes of analysis in this WSA, it is assumed that NCFCWD and its subcontractors—CON, City of Calistoga and AmCan—are limited to the proportional shares of capital payments made by each agency, which are also proportional to their SWP entitlements. That represents a conservative assumption for estimating the conveyance capacity available to deliver imported surface water supplies to the Project. On that basis, of the 140 cfs capacity of the NBA Reaches 1 and 2, NCFCWD has the right to utilize 41.8 cfs and the Solano County Water Agency has the right to utilize 98.2 cfs.
From Cordelia Forebay, Cordelia Pumping Plant sends water through one of three pipelines to the City of Vallejo (Reach 3A, 53.0 cfs), NCFCWD (Reach 3B, 52.4 cfs) or the City of Benecia (Reach 3C, 32.6 cfs). The capacity in each reach is controlled by the agencies at the terminus, so that NCFCWD has exclusive use of Reach 3B. Since that reach can convey at least 52.4 cfs, compared to NCFCWD’s allocation of only 41.8 cfs from Reaches 1 and 2, Reach 3B does not act as a limitation on conveyance of water to Napa County. Reach 3B travels from the Cordelia Pumping Plant to the Napa Turnout Reservoir located in Jamieson Canyon.
NCFCWD utilizes Reach 3B to deliver water to its three subcontractors, each of which has its own conveyance allocation, with CON having 35.6 cfs, the City of Calistoga 1.8 cfs and AmCan 8.6 cfs. Due to the restrictions in Reaches 1 and 2, those figures have been reduced proportionately, with CON having 34.0 cfs for itself and Calistoga, and AmCan having 7.8 cfs. Both CON and AmCan own and operate water treatment plants in Jamieson Canyon, where they take water from the Napa Turnout Reservoir. The City of Calistoga receives water on a wholesale basis from CON through that agency’s Jamieson Canyon Water Treatment Plant.363 AmCan treats water from the NBA at its own American Canyon Water Treatment Plant before injecting it into the AmCan water distribution system.
363 See WSA, Section 7.2.4.
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DWR is currently preparing an environmental impact report for the North Bay Aqueduct Alternative Intake Project, which would move the point of diversion for the NBA from Barker Slough to a point on the Sacramento River. From there, the new Reach 1A would convey water to the Travis Surge Tank, where it would join with water diverted at Barker Slough. The purpose of the project would be to locate the intake at a point with better water quality than currently exists in Barker Slough due to local runoff, provide greater reliability and avoid an area of sensitive habitat (which is explained in greater detail in the preceding sections). The CON and AmCan water treatment plants are capable of handling water quality at Barker Slough, but the cities would prefer higher water quality. Because the construction of the NBA alternative intake does not depend on the Napa Pipe Project, and vice versa, the two distinct projects may proceed simultaneously on separate paths.364
Both CON and AmCan have water distribution systems that convey water relatively close to the Project site, and either could provide wholesale water service or “wheel” water to the Project. In fact, CON currently provides water to the Project site for industrial purposes, and the WSA described the additional infrastructure that would be needed to provide water for the Project.365 However, as described above, NRP has not agreed to terms and conditions under which either AmCan or CON would provide wholesale or retail water service to the Project. This WSA analyzes the possibility that either AmCan or CON, or both, would provide wholesale water service to the Project, or would provide retail service under comparable terms and conditions so that such service would not impact service to existing water customers.
In order to deliver water from Jamieson Canyon to the Project, AmCan would convey water through its water distribution system to a likely connection point located on Devlin Road just south of the Devlin Road Bridge over Soscol Creek, where there is a 16-inch pipeline. This 16- inch pipeline would be extended north to the Project site along Devlin Road, Anselmo Court and the new bridge across Bedford Slough, where it would tie into an on-site water storage tank. Based on available demand and hydraulic modeling information, HSE performed a technical analysis and determined that there would be adequate capacity in the AmCan distribution system to supply the Project with potable water from this location.366
HSE also analyzed the capacity available for AmCan through the NBA, and the city’s use of that capacity in recent historical years. Out of the historical record, two years were chosen as representative of highest (2008, the “Maximum Year Scenario”) and moderate (2009, the “Moderate Year Scenario”) water usage years by AmCan. HSE compared the actual daily water use figures for AmCan with the maximum available capacity (7.8 cfs, which is 5.04 MGD), as depicted in Figure 12. That capacity figure is intentionally conservative, since it does not take into account that if CON or City of Calistoga do not use their full capacities in the NBA on a given day, AmCan can utilize that excess capacity.367 In fact, the actual daily figures from
364 See Notice of Preparation, Environmental Impact Report for the North Bay Aqueduct Alternative Intake Project (November 24, 2009) [http://www.water.ca.gov/pubs/planning/nba_aip_nop__department_of_water_resources__- north_bay_aqueduct__alternative_intake_project__notice_of_preparation_/dwr_nba_aip_nop-11-24-09.pdf]. 365 See WSA, Section 7.5. 366 See HSE Engineers, Napa Pipe Project—Water and Wastewater Feasibility Study, at § 2.4 (January 2011 Update) [Exhibit A]. 367 As noted above, AmCan is able to use additional capacity within the NBA when it is available based on an informal arrangement between all the parties with interests in the pipeline. Historically, the parties have not collectively utilized the full pipeline capacity, and therefore no party has been limited to its own share. In fact, 116 AUGUST 25, 2011
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AmCan show that the city has used more than 5.04 MGD of surface water on relatively frequent occasions.
Figure 12. City of American Canyon Daily Surface Water Use
7 Maximum Year Scenario Moderate Year Scenario 6
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Figure 13 shows that although AmCan uses its maximum daily capacity in the NBA and American Canyon Water Treatment Plant on certain days during the peak summer period, there are significant “shoulder” periods when AmCan is not using that capacity, and thus there is excess capacity available for use by others, such as the Project. Use of that excess capacity for the Project would not have any negative impact on AmCan’s water utility operations, but would facilitate the efficient use of an existing, underutilized water utility asset. As shown in Figure 13, the excess capacity during shoulder periods is as much as 2,467 AF during the Maximum Year Scenario and 3,121 AF during the Moderate Year Scenario.
HSE compared available capacity in the AmCan infrastructure to the water demands of the Project. In order to be conservative, HSE assumed that the Project would need its peak daily demands on all days, so that the figures below represent the minimum of imported surface water that would be available to the Project while utilizing the AmCan infrastructure. The calculations
within Napa County, NCFCWD has not historically monitored or reported how much capacity the various parties have used. It is anticipated that such practices may be modified in the future, as many parties are planning to utilize a greater percentage of their respective capacities. Therefore, this Supplement does not rely upon the continuation of the historical informal arrangement, but assumes that each party will be limited to its own proportional share of capacity.
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assumed that the Project will have on-site water storage of at least 1.8 million gallons that can draw down to meet water demands before an alternative water source is needed, and that those storage tanks will be refilled during the next day in which there is excess surface water capacity. The results of this analysis are that in the Maximum Year Scenario, flows exceeded 5 MGD on 39 days, and were greater than 4 MGD on 148 days, resulting in available capacity for the Project of 483 AFY (which is rounded down to 480 AFY for purposes of this WSA). In the Moderate Year Scenario, flows exceeded 5 MGD on only one day and 4 MGD on 65 days, resulting in available capacity for the Project of 620 AFY. Thus, in the Maximum Year Scenario the Project would need to utilize 137 AFY (rounded to 140 AFY) of water from another source, and in the Moderate Year Scenario the Project could rely entirely on imported surface water supplies to meet Project demands.
In addition to the use of groundwater during summer months when AmCan is using its full capacity in the NBA, there are periods when the NBA must be closed due to maintenance. In past years, this shutdown of the NBA has lasted for approximately two weeks. During that period, the Project would need to produce approximately 24 AFY of groundwater to meet all Project demands, unless the Project can secure delivery of water from another source on a temporary basis. This increases projected maximum groundwater usage to 164 AFY (140 AFY during peak summer months and 24 AFY during winter shutdowns), with minimum surface water importation of 456 AFY.
According to the analysis above, in certain years of maximum water usage by AmCan, as seen in the Maximum Year Scenario, the Project would need to supplement the use of imported surface water with water from another source. As analyzed in the WSA, the Project has access to significant groundwater resources underlying the site, with historical average usage in recent years of approximately 150 AFY without any lowering of groundwater levels or other adverse impacts.368 The likely maximum supplemental water demands of 164 AFY, as identified in HSE’s analysis, would exceed recent historical groundwater use on the Project site by a small amount. Therefore, the Project could feasibly rely on an imported surface water supply, with use of local groundwater in quantities only slightly higher than historical baseline groundwater production.
Conceptual future operations under each of these scenarios are depicted in Figure 14. The figure shows that a base of AmCan’s existing NBA supplies would be used in each month, with imported surface water supplies from the Project being used during the irrigation season from April through October. During the Maximum Year Scenario, when AmCan demands for water from the NBA would not allow the satisfaction of all water demands of the Project, groundwater would be used to meet Project demands. The figure demonstrates how the AmCan existing supplies would be conjunctively used with new imported surface water and local groundwater supplies for the Project to meet all demands of both AmCan and the Project.
368 See WSA, Section 4.11; WSA Exhibit C, at 2-8 (Table 5); WSA Exhibit E, at 5 (Table 2). According to the analysis for the Project in this Supplement, groundwater would only be used for purposes of the Project. Physically, local groundwater and imported surface water supplies would each be conveyed to a common reservoir on the Project site, from whence the blended supplies would be delivered for beneficial uses onsite. The water infrastructure as proposed for the Project would not be physically capable of supplying groundwater directly into the pipeline leading to the site from AmCan or CON, since an air gap would exist between the supply pipelines and the water supply reservoir. 118 AUGUST 25, 2011
Figure 13
ACRE FEET American Canyon’s Conveyance Capacity PER DAY (AFD) 20 Maximum Usage Scenario AMERICAN CANYON'S NORTH BAY AQUEDUCT CONVEYANCE LIMIT 15 AMERICAN CANYON'S 2,467 ACRE FEET EXCESS CONVEYANCE CAPACITY EXCESS CAPACITY 10
5 AMERICAN CANYON'S DAILY USAGE 0 JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC
ACRE FEET PER DAY (AFD) 20 Normal Usage Scenario AMERICAN CANYON'S NORTH BAY AQUEDUCT CONVEYANCE LIMIT 15 AMERICAN CANYON'S 3,121 ACRE FEET EXCESS CONVEYANCE CAPACITY EXCESS CAPACITY 10
5 AMERICAN CANYON'S DAILY USAGE 0 JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC
American Canyon has ample conveyance capacity to import additional sources of water. Maximum Usage Scenario* Surface Water Plus Backup Groundwater ACRE FEET PER DAY (AFD) 20 AMERICAN CANYON'S NORTH BAY AQUEDUCT CONVEYANCE LIMIT 15 AMERICAN CANYON'S EXCESS CONVEYANCE CAPACITY 10
5
0 JANFEBMARAPRMAYJUNJULAUGSEPOCTNOVDEC
American Canyon's Daily Usage Napa Pipe Surface Water Daily Usage Napa Pipe Groundwater Daily Usage
American Canyon has sufficient conveyance capacity to import additional sources of water.
*Chart is based on actual 2008 North Bay Aqueduct usage data, which represents a constrained year. In a normal years no backup groundwater would be required. WATER SUPPLY ASSESSMENT FOR THE NAPA PIPE PROJECT
Figure 14. Conceptual Water Operations Under Two Scenarios
Maximum Year Scenario
600
Project Groundwater Project Transfer Supply 500 AmCan NBA Supply AmCan + Project Demands AmCan NBA Demand
400
300 AF
200
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Moderate Year Scenario
500
450 Project Transfer Supply AmCan NBA Supplies AmCan + Project Demands 400 AmCan NBA Demand
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0 Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
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The analysis in this WSA focuses on water conveyance infrastructure owned and controlled by AmCan, rather than its water resources, because the Project would not rely upon the city’s water supplies and instead would be a net contributor to AmCan resources. AmCan’s most recent Urban Water Management Plan (2010) discussed overall water supplies and demands for the city, but with requirements of the Urban Water Management Planning Act did not specifically address infrastructure issues.369 As discussed above, AmCan’s imported surface water supplies are currently limited by its capacity in the NBA on peak days, and AmCan does not currently have the ability to serve new customers or expand its water deliveries to existing customers without pursuing one or more of the strategies below.
(1) AmCan could increase use of water supplies that do not require use of the NBA. This is identified as AmCan’s primary strategy in the city’s 2010 Urban Water Management Plan, with a focus on increasing use of recycled water.370 In addition, AmCan plans to increase its use of recycled water to reduce existing demands on the NBA system. By 2035, AmCan plans to eliminate the use of water from the NBA for agricultural irrigation, thus making capacity available for increased municipal demands.371 Implementation of this strategy would have a neutral or positive impact on the use of water conveyance and treatment capacity to deliver imported surface water to the Project.
(2) AmCan could improve the efficiency of water use within its service area, leading to overall lower water demands for existing customers and potentially making capacity available for new customers. AmCan has identified substantial water conservation actions to be undertaken in its 2010 Urban Water Management Plan. Compared to its 2005 Urban Water Management Plan, AmCan now expects to serve a greater population in 2025 (25,525 in 2010 versus 19,800 in 2005) with a smaller quantity of water (5,045 AFY in 2010 versus 7,026 AFY in 2005).372 As with strategy (1) above, implementation of this strategy would have a neutral or positive impact on the use of water conveyance and treatment capacity to deliver imported surface water to the Project.
(3) AmCan could build additional capacity in the NBA and its American Canyon Water Treatment Plant. To the extent AmCan pursued this strategy, it would have no appreciable impact on the Project’s ability to use excess non-peak capacity in the NBA and related facilities. Expanded facilities would continue to have significant off-peak— or “shoulder”—periods, when excess capacity would be available to meet the water conveyance and treatment infrastructure needs of the Project.
(4) AmCan could build additional storage for treated water to allow the city to fully use its pipeline and treatment capacity across a broader number of days while still being able to meet peak summer demands. This strategy would raise AmCan’s use of shoulder periods when water could be treated and diverted to storage rather than used immediately. To the extent AmCan pursued this strategy, the water purveyor for the Project would need to participate in building new storage with the city, so that the Project could continue to use excess capacity in the shallower shoulder periods. This issue would be addressed in the
369 See CAL. WATER CODE §§ 10610 et seq.; AmCan 2010 UWMP; AmCan 2005 UWMP. 370 See AmCan 2010 UWMP, at 4-8 through 4-13. 371 Id. at 3-13. 372 Id. at 3-2, 5-5. 122 AUGUST 25, 2011
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agreement between NRP and AmCan as described in Section 5.5.3. This is the type of infrastructure issue that water purveyors are continually responsible for managing on an iterative basis, and there is no reason to expect that the Project water purveyor would not be able to manage this issue successfully.
In May 2011, AmCan adopted a Zero Water Footprint Policy, under which all new customers, and existing commercial or industrial customers who request higher levels of water service, are required to offset their water demands or provide new water supplies, taking into account the limitation on NBA infrastructure. That policy includes a goal that AmCan will “[u]tilizing best management practices assign or shift commercial, industrial, and new residential subdivision water demand from water supplied by the State Water Project to more reliable alternate sources of water.”373 AmCan expects to achieve that goal by “expanding the recycled water system; exploring conjunctive use, groundwater, and groundwater recharge; partnering with other agencies to develop surface or recycled water storage facilities; and investing in options such as desalination and rainwater harvesting.”374 The policy includes a “tool box” of actions that are available to a proposed new customer, including retrofitting existing residences with low-flow fixtures, purchasing developable land as permanent open space, acquiring other water supplies, contributing toward expansion of the recycled water system and other measures that reduce existing demands in the AmCan water service area.375
Notably missing from the Zero Water Footprint Policy is the acquisition of new water supplies that would need to be conveyed through the NBA. As stated in the AmCan 2010 Urban Water Management Plan, “[i]n the City’s 2005 UWMP, water supply projects included investigating purchase of additional SWP entitlements to add to the City’s SWP Table A allotment. However, in order to improve the City’s water supply reliability, the City has moved away from this strategy as too much of the City’s water supply is water that is from the State and delivered through the NBA system.”376 Thus, AmCan has officially recognized that it cannot supply increased quantities of water through the NBA and plans to meet the demands of new customers through other means. Implementation of AmCan’s alternative strategies will allow new customers to be provided water service by AmCan, without affecting the ability of the Project to access the NBA and associated water conveyance and treatment facilities.377 The Project is unique in its ability to utilize the shoulder periods of capacity in the NBA, because of its access to local groundwater underlying the Project site. Such conjunctive use of local groundwater and imported surface water represents best management of the water and infrastructure resources of the lower Napa Valley area.
HSE sought to perform a similar analysis for available capacity in the NBA and Jamieson Canyon Water Treatment Plant for the CON, i.e., an analysis of daily flows and available capacity. CON, however, declined to provide daily flow data for this purpose, making a precise quantitative analysis impossible. Based on publicly available descriptions of CON water facilities and operations,378 it is expected that CON would have capacity available to convey
373 Id. at Appendix D, at 29. 374 Id. Regarding the potential use of groundwater by AmCan, see this WSA, Section 4.6.2. 375 Id. at Appendix D, at 31. 376 Id. at 4-13. 377 Id. at 3-12. 378 See generally WSA, Section 7.
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imported surface water to the Project, with the quantity likely to be as much as or more than could be wheeled through the facilities of AmCan. That conclusion results from the larger capacity of CON in the NBA facilities—34.0 cfs for CON as opposed to 7.8 cfs for AmCan— and the fact that CON, like AmCan, uses its largest quantity of imported surface water during the peak water demand period of July through September of each year, leaving significant “shoulder” periods when capacity is available. Unlike AmCan, the CON is not constrained by peak day infrastructure capacity. Thus, conveyance of water through CON facilities on a wholesale or wheeling basis should be possible on at least as positive terms as for AmCan.379
As mentioned above, water quality in Barker Slough during the winter months can be degraded due to local runoff in the Barker Slough watershed. While the American Canyon WTP is capable of treating water withdrawn from Barker Slough during that period to meet all drinking water quality standards, there is an increased cost from doing so. That cost would be determined as part of negotiations between NRP and AmCan and paid for by the development. The water quality in Barker Slough during winter months is within the range for which the American Canyon WTP was designed and constructed, and it is not expected that use of that water will have any significant effect on the life of the facility.380
A final issue to consider when determining the infrastructure capacity available to deliver water to the Project is the possibility of other water transfers using the NBA and associated facilities. The possibility of such transfers proves the feasibility of use of the NBA for importing surface water supplies to the Project, but might occupy otherwise available conveyance capacity. An example of such a transfer is the transaction during 2011, in which SCWA plans to import 1,000 AF at a maximum rate of 4 cfs through the NBA from Reclamation District No. 2068.381
In order to resolve this issue, this WSA has assumed that the only capacity available to import surface water to the Project is the proportional capacity controlled by AmCan. Thus, transfers by other parties that take delivery of water from the NBA, such as SCWA or the City of Vallejo, would not interfere with the importation of water to the Project. It is unknown what transfers could be expected by such parties in the future, and any specific analysis would be speculative. By making cautious assumptions about the conveyance capacity available to the Project, however, this WSA is able to conclude that the conveyance capacity estimated in this Section 5.5.1 would not be affected by other water transfers using the NBA.
5.5.2 Conveyance Through SWP Facilities
As described above, NCFCWD uses the NBA and related SWP facilities to deliver water to Napa County pursuant to an agreement with DWR. According to Section 55 of that agreement, NCFCWD has the right to use SWP facilities to convey non-SWP water, as long as the use does not interfere with other SWP supplies, and NCFCWD pays the marginal cost of transporting
379 See West Yost & Associates, Technical Memorandum No. 7: 2050 Napa Valley Water Resources Study Project, Potential Local and Regional Water Supply Projects, at 7 (October 19, 2005). 380 See AmCan 2010 UWMP, at 5-7. 381 In the Matter of License 6103 (Application 2318) Petition for Temporary Change Involving the Transfer of up to 1,000 AF of Water from Reclamation District No. 2068 to the Solano County Water Agency Administered by the Department of Water Resources (July 15, 2011) [http://www.waterboards.ca.gov/waterrights/water_issues/- programs/applications/transfers_tu_orders/docs/2318tt110418order.pdf]. 124 AUGUST 25, 2011
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such water, including power costs.382 In order to import water supplies for the Project, NRP, the water purveyor, AmCan or CON, and NCFCWD would work together to request conveyance of the Mill Creek water through the NBA and related SWP supplies on the terms and conditions expressed in that Section 55. The terms and conditions of conveyance would likely be contained in a separate water conveyance agreement between DWR and NCFCWD.
Because the strategy would be to use excess capacity of AmCan or CON, there would not be any interference with other SWP supplies, and the water purveyor and its customers at the Project would ultimately be responsible for paying the costs of conveying water through the NBA.
Because the source of the water right is Mill Creek, a tributary to the Sacramento River on which the SWP has no water rights, and the assignment and change will result in increased flows in the Sacramento River, the Project would not have any impact on SWP supplies. Because the proposal is to use excess capacity in NCFCWD’s portion of the Barker Slough Pumping Plant and NBA when it is available, the Project would not have any impact on the ability of the SWP to meet its delivery obligations, or on use of those facilities to deliver water to SCWA or the City of Vallejo.
5.5.3 Agreement with the Cities
In order to gain access to the available capacity in the NBA and local water distribution system of AmCan or CON, the Project may utilize an agreement with one or both of those cities.383 The agreement would provide that NRP will assign all its right, title and interest in and to the imported surface water supplies to the applicable city to divert and use in its discretion as part of the city’s water supply portfolio. The city can schedule diversions and conveyance through the NBA, its respective water treatment plant and the city water distribution system, in order to maximize overall deliveries of water.
In exchange for the assignment of water to the city, the city will deliver water to the Project as needed to meet its potable water demands. During peak water usage days in the highest usage months, the Project can withdraw water from storage on the Project site rather than taking delivery of water from the city. In addition, the Project water purveyor has the ability to withdraw groundwater on a temporary basis in a quantity that is equal to or less than historical usage on the Project site.
While NRP has not negotiated a final agreement with either AmCan or CON for the exchange of water as described above, such an agreement is feasible and provides distinct benefits to both AmCan or CON on one hand, and NRP on the other. Such an arrangement would provide additional water supplies to the applicable city, which are more reliable than SWP supplies and cost-competitive, and would reduce the costs for city retail water customers, by putting excess capacity to use on a compensated basis. Preliminary discussions have been held between NRP and AmCan, and no barriers to agreement have been identified. It is reasonable to expect that if
382 Water Supply Contract Between the State of California Department of Water Resources and Napa County Flood Control and Water Conservation District, as Amended [http://www.water.ca.gov/swpao/docs/wsc/NCFC_O_C.pdf]. 383 California state law includes a requirement that owners of water conveyance facilities make unused capacity available to transferors of water supplies. See CAL. WATER CODE §§ 1810-1814 (the “Wheeling Statutes”). NRP does not intend to seek access to water conveyance facilities pursuant to the Wheeling Statutes, but will rely exclusively upon voluntary agreements with facility owners.
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the Project environmental reviews are successful and entitlements acquired, agreement can be reached on water exchange between NRP and AmCan, CON or both.
Figure 15 shows the process that would be followed for gaining the necessary agreements and approvals for use of the NBA and associated facilities for the conveyance of imported surface water to the Project. As is apparent in that diagram, the process is relatively straightforward and simple. Each step consists of informal provision of information and negotiations, without a formal process. It is expected that gaining all necessary agreements and approvals would take approximately six to 12 months from Project approval.
Figure 15. Process for Gaining Access to Water Conveyance Infrastructure
Reach agreement between NRP and AmCan/CON
Gain approval from NCFCWD
Gain approval from DWR
5.6 Impacts of Climate Change on Imported Surface Water
This section analyzes the potential impact of climate change on imported surface water supplies for the Project. The potential impact on local groundwater was addressed in Section 4.10 and is expected to be different than the impact on surface water; thus, the two supplies are analyzed separately. Many of the technical reports summarized in Exhibit N, however, are applicable to and relied upon in both Section 4.10 and this Section 5.6.
To address uncertainties in the imported surface water supplies relied on by this WSA, this report summarizes the most recent reports that address the potential effects of climate change on surface water supplies, especially those in the Delta watershed. It also summarizes pertinent water management recommendations offered by state agencies, policy groups and non- governmental organizations.
Climate change is a global-scale issue. The Intergovernmental Panel on Climate Change (“IPCC”) defines climate change as:
a change in the state of the climate that can be identified (e.g., using statistical tests) by changes in the mean and/or the variability
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of its properties, and that persists for an extended period, typically decades or longer. Climate change may be due to natural internal processes or external forcings, or to persistent anthropogenic changes in the composition of the atmosphere or in land use.
As noted in Section 4.10, there is a great deal of uncertainty surrounding temperature rise predictions and the resulting impacts on local and regional climates because it is difficult to predict future greenhouse gas emissions and the resulting feedback processes in the climate system and hydrological cycle. Further, existing climate change models are imperfect and become increasingly imprecise when used to predict changes on a watershed level. Therefore, it is difficult to quantify the impacts of climate change on water supplies in the western United States or California, let alone for the Project.384
A variety of studies indicate that California water supplies have been and will continue to be impacted by climate change. As a result, climate change should be considered in estimating future water demands and evaluating potential water supplies for the region. For surface water sources of supply, climate change can shift the timing of streamflow and alter the way water supply reservoirs are managed, i.e., filling and release. For example, increased evapotranspiration may decrease streamflows. In contrast, climate change impacts on groundwater sources are largely unknown due to the high degree of variability of aquifers and site-specific effects, such as surface-groundwater interactions, pumping and rates of recharge.
Recent climate change reports recognize that impacts on surface water resources largely depend on the degree of warming and note variations regarding the impact of climate change on local and regional climates.385 Current literature suggests that global warming is likely to significantly affect the hydrologic cycle, changing California’s precipitation pattern and amount from that shown by the historical record. In fact, there is evidence that some changes have already occurred, such as Sierra snowmelt starting earlier, more runoff shifting from the spring to the winter and an increase in winter flooding frequency.386 Other potential impacts of climate change on California’s surface water resources include the possible loss of 5 million or more acre-feet of annual storage in California’s snowpack, sea level rise, increases in water temperature and variations in evapotranspiration rates.387 Higher temperatures may increase water demands for municipal and agricultural uses. These changes would place more stress on the reliability of existing flood management and water supply systems, such as Delta supplies.
As the state agency responsible for water planning and operation of the SWP, DWR is at the forefront of climate change in California and to date has conducted the most comprehensive
384 This approach to analyzing climate change has been approved by the Los Angeles County Superior Court in a case that addressed the sufficiency of a water supply assessment in a environmental impact report. See Santa Clarita Oak Conservancy, California Oak Foundation, and Santa Clarita Organization for Planning the Environment v. City of Santa Clarita, Statement of Decision, Case No. BS 084677 (Los Angeles Sup. Ct. August 15, 2007). 385 See generally Exhibit N. 386 California Department of Water Resources, Progress on Incorporating Climate Change into Management of California’s Water Resources (March 2008) [http://www.water.ca.gov/climatechange/docs/ClimaticChange_DWR- article_Mar08.pdf]. 387 Id. at 2-1 to 2-80.
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studies of the impacts of climate change on Delta supplies.388 The Delta is vulnerable to sea level rise caused by rising ocean temperatures leading to expanded water volume, and to a lesser extent, melting ice in Greenland and western Antarctica. Sea level rise is problematic because many Delta lands are located below sea level even under existing conditions. These lands are currently protected by levees and could be inundated if those levees fail. If the Delta levees fail, salt water would intrude on freshwater supplies, threatening drinking water supplies for millions of Californians.
DWR’s March 2008 report, Progress on Incorporating Climate Change into Management of California’s Water Resources, shows that for future warming scenarios, there is general consensus that greater amounts of winter-season runoff combined with static flood protection rules would lead to greater uncontrolled releases from SWP and CVP reservoirs. Reduced spring-season runoff into the reservoirs would lead to decreased water supplies and deliveries to SWP and CVP water users. Both impacts would pose challenges to maintaining SWP and CVP performance levels at present-day conditions.389
In DWR’s May 2009 Report, Using Future Climate Projections to Support Water Resources Decision Making in California, possible climate change effects to SWP and CVP operations were assessed using 12 future climate projections at mid-century and end-of-century.390 The range of results for the 12 projections is detailed throughout that report. Uncertainties in the results increase as the projections move further into the future. These studies assume that no changes were made to the existing SWP and CVP infrastructure in the future. The ongoing Delta processes and proposals for new conveyance systems are discussed above in Section 5.4.5.2.
DWR reports that increases in air temperature are expected to have significant impacts on watersheds that traditionally receive at least some of their precipitation in the form of snow. These results indicate that increases in air temperature will have a significant impact on the timing of runoff for the upper Feather River basin, which supplies the SWP, and for Mill Creek and the entire Sacramento River system. The studies indicate that the fraction of snowmelt that occurs before April 1 will increase as air temperatures increase.
DWR’s May 2009 report also examined impacts to the Central Valley Project water systems. Potential impacts of climate change on the operation of the SWP and CVP were assessed for 12 future climate projections at both 2050 and 2100. For all exceedance levels, annual Delta exports were less than current conditions for both the mid-century and end-of-century analysis periods. Agricultural crop and urban outdoor water demands were adjusted to reflect changes in precipitation. Although there is a wide range of uncertainty in sea level rise projections, for simplicity’s sake, sea level rise estimates of one-foot for the mid-century and two-feet for the end
388 California Department of Water Resources, Managing an Uncertain Future: Climate Change Adaptation Strategies for California’s Water (October 2008) [http://www.water.ca.gov/climatechange/docs/ClimateChange- WhitePaper.pdf]. 389 California Department of Water Resources, Progress on Incorporating Climate Change into Management of California’s Water Resources, at 16 (March 2008). 390 California Department of Water Resources, Using Future Climate Projections to Support Water Resources Decision Making in California, at 8 (May 2009) [http://www.water.ca.gov/50150D2F-BCAE-4CA6-A9A6- F97C571053F2/FinalDownload/DownloadId-EA43F91C8098F910D199B3CD8FBCA337/50150D2F-BCAE- 4CA6-A9A6-F97C571053F2/pubs/climate/using_future_climate_projections_to_support_water_resources_deci- sion_making_in_california/usingfutureclimateprojtosuppwater_jun09_web.pdf]. 128 AUGUST 25, 2011
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of the century were chosen for these impact studies.391 This indicates that SWP and CVP deliveries south of the Delta will be less reliable under projected future climate conditions using the current system infrastructure and operating rules. At mid-century, Delta exports are reduced by 7 percent for the lower greenhouse gas (“GHG”) emissions scenario and by 10 percent for the higher GHG emissions scenario. By the end of the century, the Delta exports are reduced by 21 percent and 25 percent, respectively. This indicates that SWP and CVP water supplies will be less reliable under projected future climate conditions using current infrastructure and operating rules.
In addition to the mid-century and end-of-the-century analysis described above, for its 2009 report DWR estimated potential deliveries for 2029 using one future climate projection which is representative of median effects on the SWP and CVP system based on results from all 12 projections. An important factor in California’s water supply reliability is the amount of water stored in reservoirs from one year to the next. This stored water is like a water supply savings account that allows water managers flexibility during single dry or multiple dry years. This water supply savings account is called reservoir carryover storage, and it is the amount of water remaining in a reservoir at the end of September that is available (carries over) for use the next water year. At mid-century, median reservoir carryover storage is reduced by 15 percent for the lower GHG scenario and by 19 percent for the higher emissions scenario.392 These reductions in reservoir carryover storage would reduce the systems’ flexibility during water shortages.
Under climate change in some years, water levels in the main supply reservoirs (Shasta, Oroville, Folsom and Trinity) could fall below the lowest release outlets, making the system vulnerable to operational interruption. By mid-century, it is expected that a water shortage worse than the one during the 1977 drought could occur in one out of every 6-8 years.393 In those years, it is estimated that an additional 575,000 to 850,000 AFY of water would be needed to meet current regulatory requirements and to maintain minimum system operations. DWR concluded that this water could be obtained through additional water supplies, reductions in water demands, or a combination of the two. For current conditions, the 2009 report concludes the system is not considered vulnerable to this type of operational interruption.394
DWR also releases bi-annual reports on the current and future for SWP water supply conditions, if no significant improvements are made to convey water past the Delta or to store the more- variable run-off that is expected with climate change. The 2009 State Water Project Delivery Reliability shows a continuing erosion of the ability of the SWP to deliver water. For current conditions, the dominant factor for these reductions is the restrictive operational requirements contained in the federal biological opinions to protect endangered fish species. For future conditions, it is these requirements and the forecasted effects of climate change.395
The studies for the 2005 State Water Project Reliability Report did not include any of the potential effects of climate change. For the 2007 report, the changes in run-off patterns and amounts were incorporated into the analyses. For the 2009 studies, the changes in run-off
391 Id. 392 Id. at 17-18. 393 Id. at 18-19. 394 Id. at 19. 395 California Department of Water Resources, 2009 State Water Project Delivery Reliability Report, at iii (2009) [http://baydeltaoffice.water.ca.gov/swpreliability/].
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patterns and amounts are included along with a potential rise in sea level. Sea level rise has the potential to require more water to be released to repel salinity from entering the Delta in order to meet the water quality objectives established for the Delta.396 One recent study found that sea level rise is likely to have a more significant impact on SWP operations than changes in the annual timing of streamflow.397 The effect of the operational restrictions in addition to the incorporation of potential climate changes impacts amounts to an estimated reduction of 970,000 AFY when the median value for annual SWP deliveries for future conditions in the 2005 report (3.57 million AFY) is compared to the updated value in the 2009 Report (2.6 million AFY).398
In light of these conclusions, both governmental agencies and non-governmental organizations recommend that water decision-makers operate existing water systems to allow for increased flexibility. Other recommendations include incorporating climate change research into infrastructure design, conjunctively managing surface water and groundwater supplies, and integrating water and land use practices. Policymakers and water suppliers in California are currently addressing climate change impacts and developing new ways to cope with the types of variability which are outside the design range of existing infrastructure.
For the Project, the analyses above mean that the water purveyor will be required to flexibly manage and conjunctively use all its water supplies, including imported surface water, local groundwater and recycled water supplies. The potential surface water supplies for the Project are senior in water rights priority to the CVP and SWP, so the federal and state projects will be reduced prior to imported surface water supplies for the Project.399 Given the large size of the junior rights for the CVP and SWP, as well as other junior water users on the Sacramento River system, those rights essentially insulate the Project from future water cutbacks. To the extent the impacts of climate change are of a magnitude large enough to impact the Project’s surface water supplies, the water purveyor should have the opportunity to participate in regional water planning efforts seeking solutions to what would be a large-scale problem. For purposes of this WSA, it can be assumed that the water purveyor would take all actions necessary to mitigate the future impacts of climate change on water supplies for the Project.
396 Id. 397 See Wang, et al., “Isolated and integrated effects of sea level rise, seasonal runoff shifts, and annual runoff volume on California’s largest water supply, Journal of Hydrology (May 2011). 398 California Department of Water Resources, 2009 State Water Project Delivery Reliability Report, at iii (2009) [http://baydeltaoffice.water.ca.gov/swpreliability/]. 399 This may have the temporary benefit of reducing AmCan’s use of its water conveyance infrastructure, making more capacity available to the Project. It should be expected, however, that AmCan would take action to correct such an occurrence, and that temporary condition would not persist (and would not be a positive development for Napa County water supplies generally). 130 AUGUST 25, 2011
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SECTION 6 RECYCLED WATER
This section analyzes the use of recycled water to meet the common area irrigation demands of the Project. The Project includes approximately 41.6 acres of irrigated landscapes and parks that will be irrigated with recycled water.400 As described in Section 3.4 of this WSA, approximately 141 AFY of Project demands can be met using recycled water. Consistent with the state policy that recycled water should be utilized whenever it is available, the Project will use recycled water for most of its landscape irrigation water demands. Recycled water cannot be used to meet interior residential and commercial water demands. In addition, the Project will not use recycled water to irrigate a small number of residential back yards covering 2.3 acres, which would not be accessible to water purveyor employees and would require maintenance by individual homeowners. Use of potable water for back yards irrigation is also consistent with the need to prevent cross-connection between the potable and recycled water distribution systems.
This WSA analyzes co-equal alternatives for supplying recycled water to the Project: the first is to purchase recycled water from the NSD; and the second is to build and operate a wastewater treatment facility on the Project site. As seen below, either of these alternatives is capable of providing sufficient recycled water resources to the Project in normal, single dry and multiple dry years for the first 20 years of the Project and beyond.
6.1 Napa Sanitation District
6.1.1 Overview of Napa Sanitation District
The Napa Sanitation District owns and operates the Soscol Water Recycling Facility south of the City of Napa and the Project site. NSD collects wastewater from the City of Napa, Silverado Country Club, the Project site and industrial areas at the Napa airport and delivers it to the SWRF for treatment. The SWRF is designed to treat 15.4 MGD of wastewater and produces up to 8.8 MGD of disinfected tertiary quality recycled water, the highest quality recognized under state regulations.401 During the wet season from November 1 through April 30, recycled water is discharged to the Napa River due to low irrigation demands in the area and a lack of storage capacity. During the dry season from May 1 through October 31, recycled water is distributed to local water users, including vineyards, industrial parks and golf courses.402
Under the National Pollutant Discharge Elimination System (“NPDES”) discharge permit currently held by NSD, the district is prohibited from discharging effluent to the Napa River between May 1 and October 31 of each year. During that period, the SWRF produces approximately 3,200 AFY of effluent that must be disposed of by distributing recycled water.403 Based on average inflows from the Project of 505,000 gpd,404 which is equal to 566 AFY, the SWRF would produce approximately 283 AFY during those critical months in addition to current supplies.
400 HSE Report, at § 4.1.1 [Exhibit A]. 401 Napa Sanitation District, Strategic Plan for Recycled Water Use in the Year 2020 at ES-1, 2-16 (August 2005) (“NSD Strategic Plan”) [Exhibit J]. See California Department of Public Health Regulations, Cal. Code of Regs., Title 22. 402 NSD Strategic Plan, at ES-1 [Exhibit J]. 403 Id. at 2-24. 404 HSE Report, at § 3.1 [Exhibit A]. AUGUST 25, 2011 131
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As of 2005, NSD supplied approximately 3,244 AFY of recycled water for use year-round, including 1,074 AFY for landscape irrigation (including turf grass), 110 AFY for agricultural irrigation and 2,060 AFY for turf grass grown on sites owned or leased by the district for reclamation purposes.405 NSD customers used recycled water for landscape irrigation purposes on 12.25 acres for commercial properties.406 NSD has estimated that it could supply another 346 AFY to expected customers using its existing infrastructure.407 That would create total recycled water deliveries of 3,590 AFY. In fact, supplying additional recycled water to customers would assist NSD in meeting the requirements of its NPDES permit, because in very wet years when irrigation demand decreases, the SWRF has a very small margin between the effluent produced and existing recycled water demands.408
6.1.2 Strategic Plan
As part of its Strategic Plan for Recycled Water Use in the Year 2020 (“NSD Strategic Plan”), which was adopted in August 2005, NSD estimated that the SWRF in 2020 could produce up to 9,800 AFY of tertiary-treated recycled water.409 The district’s stated long-term goal is to recycle all water produced at the SWRF, if funding is available for the capital facilities needed to store and distribute the water.410 The largest funding needs faced by NSD are for construction of the Silverado Extension pipeline ($33.2 million), the Los Carneros pipeline ($23.9 million), a new pump station ($360,000), increased filter capacity at the SWRF ($6.71 million), an aquifer storage and recovery system ($5.0 million) and additional segments and connections on the existing recycled water pipeline ($1.47 million). In light of the magnitude of those expenses and a current lack of funding, NSD adopted a strategy of continuing to meet its NPDES permit requirements, while being open to expansion of its recycled water system if funds become available in future.411
NSD considers new recycled water uses to be reasonable when located within 0.25 miles of a recycled water pipeline, as is the case for the Project site.412 The district considered the Project site as the location of possible industrial use of recycled water as of 2005,413 and that use could easily be modified to landscape irrigation based on construction of the Project. The quality of water produced by the SWRF is fully adequate for landscape irrigation use at the Project.414
Based on the NSD Strategic Plan, it is clear that NSD has significant recycled water resources that could supply the Project’s landscape irrigation needs. By 2020, NSD is expected to produce up to 9,800 AFY of recycled water on a year-round basis, compared to current demands of only 3,244 AFY and the ability to distribute only 3,590 AFY without significant capital expenditures. Even existing recycled water uses contain 2,060 AFY of use on NSD’s own reclamation sites (approximately 64 percent of all existing demands), for which the district does not receive any
405 NSD Strategic Plan, at 2-24 [Exhibit J]. 406 Id. at 2-4. 407 Id. at 2-24, 2-25. 408 Id. at 2-26. 409 Id. at 2-3. 410 Id. at 2-12. 411 Id. at ES-8. 412 Id. at ES-4, 2-6. 413 Id. at 2-8, 2-10. 414 Id. at 2-9. 132 AUGUST 25, 2011
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compensation and the district would willingly curtail in favor of deliveries to the Project.415 While NSD may have the opportunity to construct new pipelines to serve additional recycled water customers in 2020 or later years, the current NSD Strategic Plan does not provide funding for such significant capital facilities. Thus, according to its current plans, NSD will produce significant quantities of recycled water at the SWRF that could be used to supply the Project. A comparison between supplies and demands for recycled water from NSD is contained in Section 6.1.6.
6.1.3 MST Area Project
In consultation with the County of Napa, NSD has proposed delivering recycled water to the MST area to address groundwater decline, as described in Section 4.8 of this WSA. In a 2007 study related to serving the MST area, NSD projected recycled water demands for its current customers to be 1,094 AFY, with projected demands in 2020 of 2,598 AFY.416 NSD did not include irrigation of its own lands in the estimation of water demands, because that activity is not expected to continue if recycled water demands arise elsewhere in future.417
The potential future recycled water service area for MST would include parcels north of Imola Avenue, south of Sarco Creek and east of the City Rural Urban Limit Boundary. The total land area of the service area is approximately 5,360 acres and includes slightly more than 1,000 parcels, most of which are between 0.5 and 5 acres. The assumed service area is comprised mostly of rural residential and vineyard parcels, as well as the golf course at the Napa Valley Country Club and some small wineries.
This MST recycled water project would consist of 17.5 miles of new pipeline, four booster pump stations along the pipeline routes and a new booster pump at the SWRF. The new pipeline would be installed from the end of the Streblow Drive pipeline through the Napa State Hospital grounds and north to the MST area. A looped recycled water distribution system using existing roadways would be constructed, with one segment extending west along First Avenue and the second segment extending east along Third Avenue; both segments would then merge along Hagen Road north of the Napa Valley Country Club.418
Potential users of recycled water from NSD in the MST area are primarily commercial vineyards and single-family residences. If vineyards and single-family residences participate at 100 percent, they are projected to account for 2,304 AFY of demand.419 If, however, only 50 percent of vineyards and 40 percent of residential customers participated, that would result in demand for 1,175 AFY of recycled water in the MST area.420
Implementation of service to the MST area would require expansion of the SWRF tertiary treatment capacity by 4.5 MGD. This would include expansion of the filtration system by
415 Id. at 2-32 (indicating NSD plan to take its own lands out of service if sufficient recycled water uses arise from outside customers). 416 Brown & Caldwell, Recycled Water Expansion Hydraulic and Preliminary Engineering Analysis: Phase I Report, at 3-2, 4-1 (2007) (“Recycled Water Phase I Report”) [http://www.napasanitationdistrict.com/strategic_- plan/reports_docs.html]. 417 Id. 418 Id. at 3-3. 419 Id. at 4-2. 420 Id. AUGUST 25, 2011 133
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installing parallel filter cells adjacent to the existing filter building at the SWRF.421 Total capital costs for such reengineering of the system range from $34.7 million for 50/40 participation, to the maximum $47.5 million for total, 100/100, participation.422
In January 2009, NSD released an addendum to its preliminary analysis based on a survey of potential vineyard and golf course customers in the MST area.423 The addendum introduces an alternative MST project based on the expressed interest in recycled water that NSD identified in its survey. NSD determined that vineyards will commit to 150.5 AFY of recycled water, and Napa Valley Country Club another 200 AFY to irrigate its golf course, for a total of only 350.5 AFY, which is far less than the project as envisioned in 2007.424 Infrastructure costs for serving these potential customers are estimated to be approximately $13.5 million.425
6.1.4 North Bay Water Recycling Program
In addition to its planning efforts in the NSD Strategic Plan and for the MST project, NSD is participating as a member of the North Bay Water Reuse Authority (“NBWRA”) in a regional project to expand the beneficial use of recycled water. The environmental and engineering portion of this project are being carried out as part of the larger North Bay Water Recycling Program (“NBWRP”), under the auspices of NBWRA.
The member agencies of NBWRA include NSD, Sonoma Valley County Sanitation District, Las Gallinas Valley Sanitary District and Novato Sanitary District. North Marin Water District and the County of Napa are also providing financial and technical support for the project.426 NBWRA is planning for the NBWRP to serve recycled water to Novato urban users, southern and central areas of Sonoma Valley, the Sears Point area, Napa Salt Marsh, and the MST and Carneros East areas in Napa County.427 Water from NSD would be delivered to the MST area, but on a potentially expanded basis when compared to the stand-alone MST area project described in Section 6.1.3.
NBWRA has released a draft EIR/environmental impact statement for the NBWRP. The Sonoma County Water Agency (“SCWA”) is acting as lead agency under CEQA, and the USBR will be the federal lead agency under the National Environmental Policy Act (“NEPA”).428 The public comment period for the draft report ended on July 20, 2009, and the FEIR is scheduled to be released later in 2009. While that draft EIR has not been certified by the SCWA or adopted by NSD, and thus is subject to modification or rejection by the lead and responsible agencies, the analysis contained in that report is used in this WSA as the best available information on potential future recycled water demands from the SWRF.
421 Id. 422 Id. at 6-3. 423 Brown & Caldwell, Recycled Water Expansion Hydraulic and Preliminary Engineering Analysis: Phase 1 Report Addendum - MST Alternative (2009) (“Addendum”) [http://www.napasanitationdistrict.com/images/home/- PDFs/HydraulicAnalysisReport.pdf]. 424 Id. at 4-2. 425 Id. at 6-3. 426 See North Bay Water Reuse Authority Website [http://www.nbwra.org/about/]. 427 See Sonoma County Water Agency, North Bay Water Recycling Program DEIR at 2-6 (2009) (“North Bay DEIR”) [http://www.nbwra.org/docs/]. 428 See U.S. Bureau of Reclamation, “North Bay Water Recycling Program, California”, 74 Fed. Reg. 22175 (May 12, 2009). 134 AUGUST 25, 2011
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The NBWRP assumes that recycled water demands within the current NSD service area in 2020 will be 2,598 AFY, the same figure as was used by NSD for studying the MST area project.429 Each of the alternative projects proposed as part of the NBWRP would create additional demands for recycled water within some or all of the participating agencies, including NSD.
Alternative 1 of the NBWRP would expand recycled water programs currently in operation within each of the member agency service areas. It puts greatest emphasis on the service of local demands by the individual wastewater treatment plants. Across all the agencies, Alternative 1 would provide 6,655 AFY of new recycled water for irrigation use and 5,825 AFY for habitat restoration, and would include installation of 83 miles of new pipeline, construction of facilities onsite at the existing wastewater treatment plants to provide an additional 7.8 MGD of tertiary treatment capacity, and development of approximately 1,020 AF of new storage, primarily at existing or planned storage ponds at the wastewater treatment plants.430 At the SWRF, NSD would expand the capacity of its recycled water treatment process by 4.5 MGD and deliver approximately 3,192 AFY of recycled water to the MST area.431
Alternative 2 of the NBWRP involves development of a subregional recycled water system, taking advantage of increased storage capacity and additional pipelines under Alternative 1 to distribute recycled water more extensively throughout the project area. Across all the participating agencies, Alternative 2 would provide 11,250 AFY of new recycled water for irrigation uses and potentially 2,933 AFY for habitat restoration, and would include: installation of 140 miles of new pipelines, construction of facilities onsite at the existing wastewater treatment plants to provide an additional 15.9 MGD of tertiary treatment capacity, and development of approximately 2,220 AF of storage, primarily at existing or planned storage ponds at the wastewater treatment plants.432 For NSD, Alternative 2 would involve the construction of a longer pipeline into the MST area and delivery of 4,421 AFY of recycled water.433
Alternative 3 under the NBWRP would create a regional system that connects all four wastewater treatment plants in the project area. This alternative would maximize water reuse by allowing recycled water from any wastewater treatment plant to be delivered to any area that needs recycled water. Since the majority of the demand for recycled water lies in the area near Sonoma and Napa, the regional interconnection achieved under Alternative 3 would allow the other wastewater treatment plants to help satisfy the demand in those areas. Alternative 3 would provide 12,761 AFY of new recycled water for irrigation use and 3,085 AFY for habitat restoration, and would include: installation of 153 miles of new pipelines, construction of facilities onsite at the existing wastewater treatment plants to provide an additional 20.8 MGD of tertiary treatment capacity, and development of approximately 2,220 AF of storage, primarily at existing or planned storage ponds at the wastewater treatment plants.434 For NSD, Alternative 3
429 North Bay DEIR, at 2-32. 430 Id. at ES-13. 431 Id. at 2-12, 2-24, 2-32. 432 Id. at ES-14. 433 Id. at 2-38. 434 Id. at 2-6. AUGUST 25, 2011 135
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would include the delivery of up to 4,421 AFY of recycled water to the MST area, using the same infrastructure as under Alternative 2.435
Table 15 shows the supply and demands for recycled water within the NSD service area under each alternative for the NBWRP as of 2020. It is apparent that a minimum of 2,657 AFY of recycled water from NSD’s SWRF will be surplus to the combined demands of the existing recycled water service area and the proposed new MST area.
Table 15. NSD Recycled Water Supply, Demand and Surplus Under NBWRP (2020) Existing Recycled Total Recycled Water Recycled Surplus WWTP Water Demand for Water Recycled Project Inflow Demand Alternative Demand Water No Project 9,800 2,598 0 2,598 6,338 Alternative 1 9,800 2,598 3,192 5,590 3,847 Alternative 2 9,800 2,598 4,421 7,019 2,657 Alternative 3 9,800 2,598 4,421 7,019 2,657 Source: North Bay DEIR, at 2-31, 2-32, 2-38, 2-44. All figures expressed in AFY. Note that the quantity of Surplus Recycled Water does not equal the difference between WWTP Inflow and Total Recycled Water Demand. The Surplus Recycled Water figures were derived from the North DEIR, which does not explain this difference, but is likely based on the difference between WWTP inflows and product water, as well as other operational factors.
6.1.5 Delivery of Recycled Water Within the City of Napa Water Service Area
NSD and CON have executed an agreement (“NSD-CON Agreement”) regarding where and how NSD will deliver recycled water within the CON potable water service area.436 Pursuant to the NSD-CON Agreement, the Project site is located within the CON water service area, and thus is covered by the terms of that agreement.437 The NSD-CON Agreement, Section 2(a), provides that NSD may solicit customers and deliver recycled water within an area that is called the “ReUse Area” and includes the Project site. Thus, the NSD-CON Agreement does not block the delivery of recycled water from NSD to the Project.
In exchange for CON allowing NSD to deliver water within the ReUse Area, NSD is required to compensate CON for its loss of revenue from existing customers taking delivery of recycled water in lieu of purchasing potable water supplies from CON.438 The amount of compensation is
435 Id. at 2-44. 436 See Agreement Between City of Napa and Napa Sanitation District for Sale of Recycled Water Within City of Napa Water Service Area, City Agreement No. 7247 (August 4, 1998), found in CON UWMP, Appendix F [Exhibit B]. 437 Id. at Exhibit A. As discussed in Sections 2.3 and 5 of this WSA, even though the Project site is located within the City’s potable water service area, the City will not necessarily be the water purveyor for the Project. It is not known how NSD and the City would handle the issue of compensation due from NSD to the City under the NSD- City Agreement if the City does not serve as the water purveyor for the Project, but that compensation would not affect the ability of the Project to take delivery of recycled water from NSD. 438 NSD-City Agreement, at § 4(a) [Exhibit B]. 136 AUGUST 25, 2011
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determined based on the reduction in potable water sales by CON to its prior customers, multiplied by CON’s current water rates less certain avoided costs, and continues until the amount of CON water sales has regained its level prior to the conversion to recycled water.439 No compensation is due unless a recycled water customer, prior to taking delivery of recycled water from NSD, purchased potable water supplies from CON.440 Since CON currently sells potable water for industrial purposes on the Project site, NSD might owe compensation to CON for recycled water sales to the Project; however, CON may or may not be the water purveyor for the Project, so no compensation may be due. This is an issue to be determined between NSD and CON, and it does not substantially affect the availability of recycled water from NSD for the Project.
6.1.6 Service to the Napa Pipe Project
In response to an inquiry by NRP, the NSD Board of Directors on June 17, 2009 decided that the agency desires to be the preferred alternative for providing wastewater and recycled water services to the Project. Materials related to that decision by NSD are attached to this WSA as Exhibit K.
In order to obtain recycled water for the Project, NRP or the water purveyor will need to negotiate and execute a recycled water supply agreement with NSD. Such an agreement has not yet been negotiated, but, as noted, NSD has expressed a desire to collect and treat wastewater from the Project and supply recycled water to the Project. In addition, the NSD planning documents discussed above indicate a desire to expand sales of recycled water where feasible, including the Project site. There do not appear to be substantial reasons why the Project applicant or the water purveyor would not be able to successfully negotiate and execute an agreement with NSD. Accordingly, recycled water is considered a highly likely and reliable water supply for the Project.
As summarized in Table 16, all of the NSD planning documents discussed above demonstrate that sufficient recycled water will be available to serve the Project. The NSD Strategic Plan projects that recycled water supplies in 2020 and following years will be at least 9,800 AFY, whereas demands will be a maximum of 2,598 without an MST area project. Because the Project site is located within NSD’s current recycled water service area, the demands of the Project are included within that 2,598 figure, as provided for in the NSD Strategic Plan. However, even if that figure did not include the Project’s recycled water demands, there is sufficient surplus recycled water available under every alternative in Table 16 to meet the Project demands without impacting the availability of recycled water to other potential users.
For future water demands in the MST area, Table 16 includes figures for each of the alternatives that are currently being considered by NSD. In each of those alternatives, sufficient recycled water is available to satisfy Napa Pipe demands.
While the NSD planning documents do not offer a projection beyond 2020, the year of build-out under the CON General Plan,441 CON’s water planning documents provide that population will
439 Id. at §§ 4(a)(2), 4(b). 440 Id. at § 4(d). 441 NSD Strategic Plan, at 1-1. AUGUST 25, 2011 137
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continue to grow at a projected rate of 1.3 percent per year after 2020.442 This suggests that wastewater influent rates at the SWRF will also increase post-2020, making more water available for recycled water production. However, because NSD’s current plans call for construction of treatment facilities at the SWRF that will produce only up to 9,800 AFY, that figure is used for all future supplies. Thus, the figures for 2020 can reasonably be extended to 2030 to provide a 20-year water planning horizon for the Project.
Table 16. NSD Recycled Water Supplies and Demands 2020 Alternatives Stand-Alone MST Project NBWRP
2005 No MST Project MST 50/40 Project MST 100/100 Project Expressed Interest MST Project Alternative 1 Alternative 2 Alternative 3 Existing Service Area Demands 1,184 2,598 2,598 2,598 2,598 2,598 2,598 2,598 MST Service Area Demands 0 0 1,175 2,304 351 3,192 4,421 4,421 Total Projected Demands 1,184 2,598 3,773 4,902 2,949 5,590 7,019 7,019 Projected Supplies 3,590 9,800 9,800 9,800 9,800 9,800 9,800 9,800 Surplus Recycled Water 2,406 6,338 6,027 4,898 6,851 3,841 2,657 2,657 Sources: NSD Strategic Plan; Recycled Water Phase I Report; Addendum; North Bay DEIR. All figures in AFY.
6.2 On-Site Wastewater Treatment Plant
6.2.1 Basic Description
As explained above, all non-potable Project demands (common landscaping in commercial, multifamily and industrial areas, and parks) will be served with recycled water. An alternative to obtaining recycled water from NSD is to site and construct a wastewater treatment plant within the Project area. The location of a treatment plant would be on the southeast corner of the property, adjacent to the potable water treatment, storage and pumping facilities.443 At this location, the wastewater treatment plant could receive wastewater flows from the Project, treat them to tertiary levels and pump back recycled water into the Project’s recycled water system for non-potable uses.444
Approximately 10 percent of the Project’s indoor water usage is estimated to be consumptive and the remaining 90 percent of wastewater flows would be conveyed to the wastewater collection and treatment system.445 At the end of Phase 1 of the Project, the average daily wastewater
442 CON UWMP, at 5-3. 443 HSE Report, at § 3.4 [Exhibit A]. 444 Id. at § 3. 445 Id. at § 3.1. 138 AUGUST 25, 2011
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flows are projected to be 197,000 gpd. After Phase 2, the average daily flows are projected to be 351,000 gpd. At build out, the average daily flow from the Project is projected to be 505,000 gpd.446
The proposed onsite wastewater treatment facility will be designed to treat the projected peak day design flow of 720,000 gpd.447 The facility will consist of a 600,000 gallon sewage influent tank, membrane bioreactor, filters, disinfection unit and pump station unit.448 A recycled water storage tank will feed irrigation lines and will have its own pumping system that will pressurize the proposed irrigation system. The tank will have an air-gapped potable water backup connection to ensure that there is a reliable supply of water to the recycled water distribution system.449 This is characteristic for recycled water systems as it provides reliability and flexibility to the system. However, it is not expected that potable water will be commonly used, and therefore has not been included as a water demand.450
Recycled water will be delivered to the Project’s park and public landscaping areas through a recycled water piping system.451 At build out, the peak day irrigation demand for recycled water is projected to be 259,000 gpd, which is 51 percent of recycled water production from the onsite wastewater treatment plant. In other words, the treatment plant can produce approximately twice as much recycled water than is required by the Project on the peak day. Thus, there will be sufficient supplies of recycled water to meet the irrigation demands of the Project. The same will be true for the Project after Phase 1, when 197,200 gpd of wastewater will be available to meet peak day demands of 93,800 gpd, and after Phase 2, when 351,000 gpd of wastewater will be available to meet peak day demands of 211,000 gpd. These values are shown in Table 17.
Table 17. Recycled Water Availability from Onsite Treatment Plant After Phase 1 After Phase 2 After Phase 3 Recycled Water Supply 197,000 351,000 505,000 Peak Day Demand 94,000 211,000 259,000 Surplus (Deficit) 103,000 140,000 246,000 Source: HSE Report, at § 3.1 [Exhibit A].
Surplus recycled water will be used to create a system of freshwater wetlands; overflow will be sent to Bedford Slough, a tributary to the Napa River.452 Discharge of recycled water to wetlands is beneficial as it creates habitat for local wildlife and creates a year-round freshwater marsh.453 All on-site recycled water reuse facilities will comply with the California Department
446 Id. 447 Id. at § 3.4.3. 448 Id. 449 Id. 450 Id. 451 Id. at § 3. 452 Id. at § 4.2. 453 Id. at § 4.2.2. AUGUST 25, 2011 139
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of Public Health Standards.454 In addition, all discharges will comply with the NPDES permitting requirements imposed by the California Regional Water Quality Control Board.
If an onsite wastewater treatment plant is utilized for the Project, it will be owned and operated by a private sewer company. That sewer company would be organized as either an investor- owned, public utility company regulated by the CPUC or a non-profit mutual benefit corporation. The sewer company could be combined with a private water company, if such an entity is formed to serve as the water purveyor described in Section 2.3 of this WSA. Even though the Project site is located within the service area of NSD as defined by LAFCO, the site would not need to be de-annexed from that service area or obtain any approval from LAFCO since private sewer companies do not fall within the jurisdiction of that agency. A public utility sewer company would need to obtain a certificate of public convenience and necessity from the CPUC prior to acquiring or operating the wastewater treatment facilities,455 while a mutual corporation would not need to obtain approval from any agency other than the County of Napa. A legal opinion regarding these organizational issues is attached to this WSA as Exhibit L.
6.2.2 Reliability Assessment
The HSE Report includes design criteria for an onsite WWTP, along with proposed operation and on-site reuse and surface water discharge strategies. There do not appear to be substantial reasons why NRP would not be able to successfully construct an onsite WWTP and re-use the tertiary treatment water on-site for landscape irrigation at the Project. Accordingly, recycled water created from the Project’s own supply of wastewater at an onsite WWTP is considered a highly feasible and reliable water supply for the Project, and represents a co-equal option to purchasing recycled water from NSD. If for some reason recycled water were not available on a temporary basis, it could be replaced by groundwater from the potable water system. Because such use of groundwater would be temporary, it would not have any significant impact on the groundwater supplies discussed in Section 4 of this WSA.456
454 Id. at § 4.1. 455 See CAL. PUB. UTIL. CODE §§ 216, 230.6, 1001. 456 Stetson Report, at 4-2 [Exhibit C]. 140 AUGUST 25, 2011
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SECTION 7 CITY OF NAPA WATER SUPPLIES
The City of Napa (“CON”) has requested that this WSA and the environmental review for the Project evaluate the possibility of CON water service to the Project. Because CON is not currently expected to supply water for the Project, the CON water supply analysis is contained in this separate Section 7. In addition to analyzing the availability of CON water for the Project, this section also reviews CON’s infrastructure capability to serve the Project in the present and future.
Information in this section has been derived from official reports prepared or adopted by CON, especially the City of Napa, Urban Water Management Plan 2005 Update (“CON UWMP”) and West Yost & Associates, 2050 Napa Valley Water Resources Study (October 2005) (“2050 Study”). The CON Urban Water Management Plan 2010 Update (2011) (“CON 2010 UWMP”) is discussed in Section 7.5.
7.1 City of Napa Service Area
7.1.1 Boundaries
CON serves a water utility service area encompassing much of the lower Napa Valley and extending up the foothills on the east and west sides of the valley. CON’s water service area contains three boundaries of importance, as shown on Figure 16 below: (1) a designated water service area, which is coterminous with CON’s sphere of influence as determined by LAFCO; (2) the Rural Urban Limit Boundary (“RUL”); and (3) the CON city limits.457 CON serves the vast majority of its customers inside the RUL, but CON does provide water service outside the RUL to customers in the Monticello Road/Silverado Resort community and the independent Congress Valley Water District, as well as accounts along the Conn Transmission Line.458 As of 2002, CON provided water service to 2,187 connections outside its city limits.459
The Project site is located within CON’s designated water service area, and the southwestern portion of the Project site is located within the RUL. The remainder of the Project Site is located outside the RUL, and the whole Project site is located outside the city limits.460 CON currently provides water service to the Project site, although, as noted above, the Project applicant and CON have not reached agreement on the terms and conditions under which CON might continue to provide water service to the Project.
457 CON UWMP, at 2-1, Figure 2-1 [Exhibit B]. 458 Id. at 2-1. 459 See County of Napa, Napa County General Plan Update Draft Environmental Impact Report, at 4.13-19 (February 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&exturl=http://www.napacountygeneralplan.- com/], ultimately certified in County of Napa, Napa County General Plan Final Environmental Impact Report, State Clearinghouse No. 2005102088 (December 20, 2007) [http://www.co.napa.ca.us/fileframe.asp?section=gov&- exturl=http://www.napacountygeneralplan.com/]. 460 See id.; LAFCO, Comprehensive Study of the City of Napa Service Review Report at 3, 5-7 (April 2005) [http://www.napa.lafco.ca.gov/uploads/documents/Municipal%20Service%20Review-City%20of%20Napa%20200- 5.pdf]. AUGUST 25, 2011 141
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Figure 16. City of Napa Water Service Area
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A city that chooses to provide water utility service is obligated to furnish water without discrimination to all members of the public within its service area who apply for water service, upon such applicants complying with reasonable rules and regulations the city may lawfully establish.461 A municipality may refuse to provide water service only if it is complying with its own reasonable rules and regulations.462 Whether the rules and regulations adopted by a municipality for the extension of water service are reasonable depends on the facts and circumstances of each case. One key question is whether the rules and regulations are genuinely designed to ensure the adequacy of water supplies and infrastructure, or whether such adequacy is merely a pretext for another policy, such as no-growth. Property owners within a city’s designated water service area obtain an equitable right to water that has been appropriated for dedication to the service area.463 Where an existing water distribution pipeline is available to provide new service, the city has an obligation to provide water service under reasonable rates and charges.464
Since LAFCO has included the Project site within CON’s designated water service area, and because CON has chosen to provide water service to other parties within this service area but outside the RUL, including currently providing water to the Project site for industrial purposes, CON has legal authority to serve the Project. Based on the general policies of LAFCO, that agency’s approval might be required for an extension of service to the Project; such an extension would be consistent with LAFCO policies and would be expected to be approved.465
7.1.2 Population and Demographics Within CON Service Area
The dominant land use within CON’s water service area is residential development.466 As of the latest figures from 2005, more than 90 percent of CON’s water accounts were single-family or multi-family residential.467 Commercial and institutional customers are primarily confined to the downtown area and shopping complexes along several major streets. CON serves approximately 20 agricultural accounts, which are primarily located along the Conn Transmission Main. By agreement, these are interruptible services that can be cut off in times of water shortage.468
Recently, CON has seen increasing infill development within the RUL portion of its water service area, reflecting the city’s housing needs and the expansion of tourist accommodations to support the wine industry. The CON UWMP and the 2050 Study both employ a per capita methodology to calculate future demand projections. For 2020 and beyond, the per capita method is based on population within the RUL only and a constant amount (900 AFY) is added to the water projections to account for expected consistent demand outside the RUL.
461 Nourse v. City of Los Angeles 25 Cal. App. 384, 385-386 (1914). See also Glenbrook Development Co. v. City of Brea 253 Cal. App. 2d 267, 277 (1967); Hansen v. City of San Buenaventura, 42 Cal.3d 1172 (1986); Scott S. Slater, California Water Law and Policy § 14.01.2 (2006). 462 See Dateline Builders, Inc. v. City of Santa Rosa, 146 Cal.App.3d 520, 530-32 (1983). See also Swanson v. Marin Municipal Water Dist., 56 Cal.App.3d 512, 522-23 (1976). 463 People ex rel. City of Downey v. Downey County Water Dist., 202 Cal.App.2d 786, 796-97 (1962). 464 Nourse v. City of Los Angeles, 25 Cal.App. 384, 385 (1914); Marr v. City of Glendale, 40 Cal.App. 748, 752 (1919). 465 See footnote 49. 466 CON UWMP, at 2-1 [Exhibit B]. 467 Id. 468 Id. AUGUST 25, 2011 143
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The CON UWMP and 2050 Study do not expressly analyze the potential water demands and supplies for the Project or other redevelopment of the Project site. Water use on the site has been included in historical water demands satisfied by CON, and existing industrial water uses on the Project site are reasonably included within the 900 AFY assumed for demands outside the RUL.
Table 18 lists the projected population of the RUL from 2005 through 2050, as derived from the Association of Bay Area Governments (“ABAG”) Projections 2003 forecasting document. CON’s General Plan assumes RUL build-out by 2020, so a nominal growth rate of 0.5 percent per year is used by the city to estimate post-2020 populations. The Projections 2005 ABAG study and subsequent studies show somewhat lower RUL population projections, but CON has continued to rely on the Projections 2003 data in its water supply planning documents because the data is the most conservative (highest) for planning purposes.469
Table 18. Projected Population of the City of Napa 2005 2010 2015 2020 2025 2030 2050 Population 81,200 86,000 89,900 93,000 95,350 97,750 108,010 in RUL
Source: CON UWMP, at 2-3 [Exhibit B]; 2050 Study, Tech. Memo 2, at 7, Table 5 [Exhibit D].
7.2 Water Demands
This section analyzes the historical and projected water demands of users within the CON water service area.
7.2.1 Historical Water Use by Customer Type
The CON water distribution system is fully metered, excluding standby fire sprinkler accounts, and customers are billed by volume of use. The system currently is in excess of 24,000 accounts. The most recent account survey data available is that in the CON UWMP, summarized in Table 19.
Recent annual water use for these accounts is summarized in Table 20. With known unmetered uses and unaccounted-for water included, the table reflects the true total demand on the system for all retail customers inside the CON water service area. While more than 20,000 accounts are single-family residential, just over half of the actual water demand comes from this sector. The commercial sector represents a disproportionate share of demand, with hotels and other businesses that serve the public at large. Industrial use is not a significant component of Napa’s demand, and government demand is comparable to the landscape irrigation sector, each consuming upwards of 700 AFY in recent years. The miscellaneous accounts in the tables include hydrant meters used for construction projects, along with manually invoiced accounts like the Napa State Hospital.
469 Id. at 2-3. 144 AUGUST 25, 2011
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Table 19. City of Napa Historical Accounts by Customer Type Customer Type Number of Accounts
2000 2001 2002 2003 2004 Single-Family Residential 20,273 20,524 20,563 20,733 20,904 Multi-Family Residential 1,364 1,367 1,360 1,365 1,379 Commercial 1,418 1,424 1,421 1,424 1,430 Industrial 3 2 2 2 2 Government 240 242 242 241 240 Landscape Irrigation 204 209 221 222 252 Agricultural Irrigation 11 14 15 16 16 Miscellaneous Accounts 38 39 42 40 38 Total 23,551 23,821 23,866 24,043 24,261 Source: CON UWMP, at 5-1, Table 5-1 [Exhibit B].
Landscape irrigation use is obviously highest in the summer months. CON requires all projects with 5,000 square feet or more of landscaping to have a dedicated irrigation account. Agricultural irrigation use fluctuates based on weather conditions and the vineyards’ use of wells and other alternative sources. Service to vineyard accounts is stopped when CON declares a municipal water shortage, acting as a limited type of conjunctive use of CON and other water sources, such as groundwater.
Table 20. City of Napa Historical Demand by Customer Type Customer Type Annual Water Use 2000 2001 2002 2003 2004 Single-Family Residential 7,161 7,493 7,561 7,443 7,914 Multi-Family Residential 2,017 2,090 1,975 1,932 1,934 Commercial 2,026 2,033 2,015 1,941 2,002 Industrial 2 1 1 9 1 Government 712 737 674 457 731 Landscape Irrigation 529 556 662 654 770 Agricultural Irrigation 198 172 170 110 173 Miscellaneous Accounts 819 833 862 670 594 Known Unmetered Uses 89 66 102 45 45 Unaccounted For Water 1,817 1,919 2,096 1,083 1,051 Total 15,370 15,900 16,118 14,344 15,215 Source: CON UWMP, at 5-2, Table 5-2 [Exhibit B]. All water use figures expressed in AF.
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Overall, residential water use makes up 70 percent of the total, with 56 percent for single-family plus 14 percent for multi-family residences. Commercial users consume the next largest share at 14 percent, with the remaining 16 percent divided among the other customer types. These percentages are not expected to change significantly as CON experiences mixed-use development in future that is strongly weighted toward residential.470 In that respect, the Project is similar to other anticipated future development within the CON water service area.
7.2.2 Demand Projection and Methodology
To project total CON retail demand for future years, both the CON UWMP and the 2050 Study employed the per capita demand method. This method showed somewhat higher water use projections than a land use method, and the higher per capita results are used for conservative planning purposes.
For the years prior to the General Plan build-out in 2020, the 2050 Study first assumed a current year 2005 total system demand of 15,370 AF, slightly higher than actual demand for the two previous years and matching the use patterns seen in 2000.471 For 2010 to 2015, it was assumed that total system demand will grow at the same rate as the population served. A growth rate of 1.3 percent per year is used, based on the average annual population growth over the past decade.
For the year 2020 and beyond, the 2050 Study used a conservatively high year 2020 RUL population estimate from ABAG and employed the techniques and assumptions described in the following paragraphs:
• Baseline Per Capita Demand. A baseline per capita demand of 180 gallons per capita per day (“gpcd”) was assumed for the population inside the RUL. This is a conservatively high gpcd based on the average per capita demand on the system in the early 2000s. It represents a 4 percent reduction in gpcd compared to the mid-1980s average prior to the last major drought of 1987-1992. The 4 percent reduction is attributed to permanent water conservation programs instituted by CON, and is a blended figure for all development prior to 2005, including both older and newer construction.472 New construction following 2005 can be expected to have an even lower gpcd due to current building practices, such as the installation of water-saving appliances and fixtures, and using past construction as a predictor can significantly overestimate the water demands of future development.
• Demand Inside the RUL. This demand is calculated by using 180 gpcd and the population within the RUL.473 Because the baseline 180 gpcd included unaccounted-for water, that amount is stripped out by dividing by 1.1 (using a figure of 10 for unaccounted-for water). The projected RUL population data for 2020-2030 were shown in this WSA above. The ABAG projection of 93,000 is used for 2020. After the RUL
470 Id. at 5-3. 471 Id. 472 Id. 473 The City’s 180 gpcd figure includes both indoor and outdoor water uses, since both rely on potable water supplies. Typically, over half of all residential water use occurs outdoors. The City’s approach differs from that taken in this WSA, since the Project is planned to use recycled water for outdoor uses. Thus, the potable water demands of the Project only include indoor water uses. 146 AUGUST 25, 2011
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build-out in 2020, population is assumed to grow at a nominal rate of 0.5 percent per year.474
• Demand Outside the RUL. This demand is assumed to be constant at 900 AFY based on Master Plan data.475 As noted above, this demand includes historical and existing industrial uses on the Project site but does not include the redevelopment contemplated by the Project.
• Recycled Water Adjustments. A 300 AFY addition for projected Napa State Hospital demands is included rather than historical demands of 400 AFY, due to an assumed switch to recycled water from NSD for non-potable use at the Hospital. A reduction of 166 AFY accounts for the fact that the Napa Municipal Golf Course and Kennedy Park have already switched to NSD recycled water supplies.476
• Veterans Home. CON assumes the possibility of supplying 100 AFY to the California Veterans Home in Yountville.
• Water Conservation. CON has expanded its conservation programs to achieve permanent long-term demand reduction. The 2050 Study assumed an additional 6 percent conservation savings will be achieved by 2020. This means a total conservation savings of 10 percent compared with the pre-drought mid-1980s.477 The additional 6 percent water conservation for 2020 and beyond has the effect of reducing total projected CON demands by 1,091 AFY by 2020, 1,117 AFY by 2025 and 1,143 AFY by 2030.478
• Unaccounted-For Water. Unaccounted-for water is assumed to be 10 percent of demand, based on the range of 7-13 percent experienced dating back to 2000.
Based on the methodology above, CON has calculated its projected water demands from 2005 through 2050. These figures are shown in Table 21 and reflect normal year demands after taking into account long-term conservation savings as described above. For its planning purposes, CON assumes that drought year demands will be 15 percent below these normal year demands.479
474 Id. 475 Id. 476 Id. 477 Id. 478 Id. at 5-4. 479 Id. See also 2050 Study, Tech. Memo 2, at 2 [Exhibit D]. The City’s approach to projecting normal versus dry year demands differs from the method used in this WSA for the Project, which projects that dry year demands will remain the same as normal year demands. The method used in this WSA for Project demands is appropriate because it is more conservative and reflects the hardening of demands for newer developments that include greater water conservation measures from the outset. This WSA does utilize the City’s reduced water demand figures for non- Project demands, because of deference to City planning efforts and the ability of older construction to reduce water demands more easily during dry periods. AUGUST 25, 2011 147
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Table 21. City of Napa Total Projected Water Demands (2005-2050) Single and Multiple Dry Year Normal Year Demands Year Demands 2005 15,370 13,065 2010 16,395 13,936 2015 17,489 14,866 2020 18,798 15,978 2025 19,243 16,357 2030 19,699 16,744 2050 21,643 18,397 Source: CON UWMP, at 5-4, Table 5-3 [Exhibit B]; 2050 Study, Tech. Memo 2, at 2 [Exhibit D]. All figures expressed in AFY.
7.2.3 Projected Water Use by Customer Type
The total water demand projections for CON in Table 20 are broken down by customer type in Table 22. Industrial usage will continue to represent a very small portion of demand in future, while residential use will continue to dominate. The commercial sector will grow to serve the increase in population, and new hotels are anticipated to serve wine country tourists. CON is also expecting to sign additional interruptible surplus water agreements with vineyard customers.
Table 22. City of Napa Projected Water Demands by Customer Type Water Demands Customer Type 2005 2010 2015 2020 2025 2030 Single-Family Residential 7,807 8,329 8,887 9,554 9,781 10,013 Multi-Family Residential 1,908 2,036 2,172 2,335 2,390 2,447 Commercial 1,975 2,107 2,248 2,417 2,474 2,533 Industrial 1 2 2 2 2 2 Government 721 769 821 882 903 925 Landscape Irrigation 760 810 865 930 952 974 Agricultural Irrigation 171 182 194 209 214 219 Miscellaneous Accounts 585 625 665 715 733 750 Known Unmetered Uses 45 45 45 45 45 45 Unaccounted For Water 1,397 1,490 1,590 1,709 1,749 1,791 Total 15,370 16,395 17,489 18,798 19,243 19,699 Source: CON UWMP, at 5-4 [Exhibit B]; 2050 Study, Tech. Memo 2, at A-4 [Exhibit D]. All figures expressed in AFY.
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7.2.4 Deliveries to Other Agencies
In addition to its retail sales to customers within its water service area, CON also delivers water to the Cities of American Canyon, St. Helena and Calistoga and the Town of Yountville on a wholesale basis. These agencies are wholesale customers who provide their own respective sources of supply and merely benefit from CON’s treatment and transmission facilities.480 They are charged wholesale rates for treat-and-wheel service. Accordingly, these water delivery arrangements do not impact CON supplies and are excluded from the retail demands analyzed in CON water planning documents and this WSA.
On April 7, 2009, the Napa City Council approved a new contract to provide additional wholesale water to St. Helena. The old agreement, dating to 2006, allowed St. Helena to buy between 200 and 400 AFY from CON, depending on how much water from the SWP was available to CON, in exchange for St. Helena transferring 1,000 AFY of SWP entitlement to CON that St. Helena had acquired from the Kern County Water Agency. The new contract doubles that amount to between 400 and 800 AF.481 It also allows St. Helena to take delivery of water throughout the year. Under the old agreement, the Napa-St. Helena connection was closed during the peak-demand summer months. The agreement is effective through 2034, provided that the SWP maintains its agreement with the CON. CON will continue to charge St. Helena its standard rate for customers located outside the city limits, which currently is $1,860 per AF. The St. Helena supply and demand is accounted for in this WSA by adding to the CON supplies in Section 7.3.3.1 the difference between the St. Helena supply and its highest demands, i.e., 1,000 AFY minus 800 AFY, which equals 200 AFY.482
CON has also executed a new water delivery contract in 2009 with the Town of Yountville. In exchange for the Town of Yountville assigning its interest in SWP supplies to CON, CON agreed to deliver water to Yountville for fire flow and emergency needs, not to exceed 25 AFY.
7.2.5 Other Proposed Development Projects
While the CON UWMP and 2050 Study project future population and development growth and accompanying water demands in the CON water service area, specific land development projects are also the subject of water supply planning efforts under SB 610 and CEQA. Several potential projects have been identified that would request water service by CON. Those planning efforts are discussed below for consistency with the CON UWMP and 2050 Study conclusions. In addition, this WSA has incorporated information from those project documents where relevant.
First, CON water supplies were recently analyzed in the Gasser Master Plan Final Environmental Impact Report.483 Proponents of the Gasser Master Plan requested water service from CON for residential, commercial, community facilities, landscape irrigation and firefighting purposes on
480 CON UWMP, at 5-6. 481 City of Napa Website [http://www.cityofnapa.org/images/cityclerk/Granicus/2009/Apr7/15a_apr7_2009.pdf]. See also Saint Helena Star, “St. Helena Will Receive More Napa Water” (April 16, 2009) [http://www.sthelenastar.com/articles/2009/04/16/news/local/doc49e698ff3453b091805754.txt]. 482 City of Napa Website [http://74.205.120.199/index.php?option=com_wrapper&Itemid=673] (Council agenda). 483 City of Napa, Gasser Master Plan Final EIR, State Clearinghouse No. 2003032055 (August 16, 2006) (“Gasser FEIR”) [http://www.cityofnapa.org/images/redevelopment/soscolgatewaydocs/comp%20gasser%20master%20plan- %20draft%20eir.pdf]. AUGUST 25, 2011 149
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an 80-acre site located within the city limits. Development of the proposed project is projected to increase demands for water by increasing the total population of the city by 1,409 residents, based on the addition of up to 500 housing units, 24 single-resident occupancy units of transitional housing, 60 homeless shelter beds and commercial and office space.484
The Gasser Master Plan FEIR uses water demand factors similar to those presented in this WSA for the Project,485 and projects that the total increased water demands will be an average of 144,832 gpd, which is equal to approximately 162 AFY.486 With the addition of 10 percent unaccounted-for water and an additional 10 percent contingency for potential project changes, water demands of the project could be as high as 198 AFY.487 The FEIR concludes that the impacts of the project on CON water supplies would be less than significant.488 Construction of buildings at the Gasser Master Plan site has begun, although it is expected to take several years for completion of the project.
Second, the 144-acre Ghisletta/Horseman’s site is located south of the CON city limits but within the RUL. CON intends to annex the area before development. Projected uses for the land under the CON General Plan include single-family detached residential, multi-family residential and business park, light industrial or warehouse uses. These uses will require refinement through subsequent master planning and environmental review efforts. The maximum total water demand for these uses on the site has been estimated by CON to be approximately 609 AFY of potable water, including 10 percent for unaccounted-for water and 10 percent as contingency based on the very preliminary information underlying the demand estimate.489
Third, the Pacific Coast/Boca site contains 82.4 acres located south of the CON city limits outside of the RUL. The site is used for industrial purposes, but the County recently identified it as a “study area” in its June 3, 2008 General Plan Update. The study proposes two development alternatives: residential, retail and office use; or industrial, business park and warehouse use with limited retail use. Total water demand for the residential option is projected to be 238 AFY, and total water demand for the industrial option is projected to be 171 AFY, including 10 percent for unaccounted-for water and 10 percent for contingencies based on the preliminary stage of planning efforts.490 For further planning analysis, this WSA uses the higher water using residential alternative.
A fourth project proposed within the CON water service area is the St. Regis Napa Valley Resort, which would be a destination resort on a 93-acre portion of the Stanly Ranch, located near the intersection of Stanly Lane and Highway 12/121 within the city limits. CON published a draft EIR for the project on August 27, 2009. The resort site is currently planted with
484 Id. at 4.12-14. 485 Id. 486 Id. at 4.12-14, 4.12-15. 487 West Yost & Associates, Technical Memorandum: Task 1: Water Demand and City Water System Hydraulic Impacts, Project No. 424-02-07-05, at 9 (August 21, 2008) (“WYA Technical Memorandum”) [Exhibit M]. 488 Gasser FEIR, at 4.12-16. 489 WYA Technical Memorandum, at 9-11 [Exhibit M]. 490 Id. at 11. Note that the demand figures in Table 7 of the WYA Technical Memorandum do not appear to be arithmetically correct for the Pacific Coast/Boca site. However, that study did not include the demands from a Pacific Coast/Boca project within the hydraulic impacts analysis that were its main purpose. In the absence of further information regarding water demands on the Pacific Coast/Boca site, this WSA utilizes the figure of 238 AFY as the best available data. 150 AUGUST 25, 2011
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vineyards and obtains water supplies through an existing connection to the CON potable water system. The current vineyard uses an estimated 60,560 gpd. Projected water demands for the project are 117 AFY of potable water and 68 AFY of non-potable water for irrigation. With the addition of available recycled water provided by either NSD or an onsite treatment facility, it is expected that recycled water would be used for irrigation and potable water would be used for domestic use. The draft EIR finds that the increase in potable water demands on the property will have a less than significant impact on CON water supplies, because the project will offset the increase in potable water demand by connecting other water users to recycled water supplies, and existing water demands on the property were included in the CON UWMP.491
The projected potable water demands from those four projects are set forth in Table 23. It is expected that all water demands will be met from CON water supplies, as described below.
Water demands from the Gasser Master Plan, Ghisletta/Horseman site and St. Regis Napa Valley Resort are included within CON’s projected water demands shown in Table 21. The demands associated with potential development of the Pacific Coast/Boca site are not included in Table 21, but CON has not committed to serving any development on that property. Because there is no certainty that CON will provide water service to the Pacific Coast/Boca project, water demands for that project have not been developed with specificity, and in order to distinctly identify the water supply impacts of the Napa Pipe Project, this WSA does not include the Pacific Coast/Boca project in CON’s projected water demands.
Table 23. Projected Potable Water Demands from Future Projects in City of Napa Water Service Area Required Supply Project (AFY) Gasser Master Plan 198 Ghisletta/Horseman 609 Pacific Coast/Boca (Residential Option) 238 St. Regis Napa Valley Resort 117 Source: WYA Technical Memorandum, at 9-11 [Exhibit M].
7.2.6 Demand Management
The water demands analyzed above do not include the impact of certain actions that may be taken by CON or its water customers in future for the purpose of intentionally reducing water consumption. The following sections address CON actions related to water conservation, water shortage contingency planning and temporary water use prohibitions and consumption
491 See City of Napa, St. Regis Napa Valley Project Draft Environmental Impact Report, State Clearinghouse No. 2009032009 (August 27, 2009) [http://74.205.120.199/index.php?option=com_content&task=view&id=567&- Itemid=681]; City of Napa, Notice of Preparation, St. Regis Napa Valley Project, at 6-7 (March 3, 2009) [http://www.cityofnapa.org/images/CDD/planningdivisiondocs/stregis/stregisnapavalley_nop_upload.pdf]. AUGUST 25, 2011 151
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reductions. CON communicates its water conservation efforts to customers with a page on the city website.492
7.2.6.1 Water Conservation
CON implements permanent water conservation measures including school education, public information and an aggressive toilet replacement program.493
In December 2002, CON joined the California Urban Water Conservation Council (“CUWCC”), a consensus-based partnership of urban water suppliers, public advocacy organizations and other parties concerned with urban water supplies. The CUWCC oversees the Memorandum of Understanding Regarding Urban Water Conservation in California (“MOU”) which sets forth BMPs in water use efficiency.
When admitted to the CUWCC in 2002, CON became a signatory to the MOU. MOU signatories agree to make a good faith effort to implement all 14 BMPs recognized by the CUWCC. Each BMP has a specific implementation schedule and coverage requirement. Water purveyors periodically file BMP progress reports directly on the CUWCC web site. The following is a summary of CON’s BMP implementation:494
• BMP 1: Water Survey Programs for Single-Family and Multi-Family Residential Customers. CON instituted a Water-Wise Home Survey Program in December 2003. Marketed to all residential customers, the program includes a site visit by a Water Conservation Representative who checks leaks, plumbing fixture flow rates and irrigation system performance. If warranted, customers are offered free low-flow showerheads, faucet aerators, toilet flappers, toilet replacement program information and irrigation scheduling and maintenance tips.
• BMP 2: Residential Plumbing Retrofit. CON initiated a program to distribute low-flow showerheads, faucet aerators and toilet flapper valves in the early 1990s. CON has considered a customer survey to determine whether 75 percent of residential accounts are now fitted with low-flow showerheads. If so, CON will have already met the CUWCC coverage requirement for this BMP.
• BMP 3: System Water Audits, Leak Detection and Repair. CON completes an annual prescreening audit of its distribution system to determine if metered sales plus other verifiable uses account for at least 90 percent of total supply into the system, i.e., unaccounted-for water is less than 10 percent. If not, then a full-scale system audit is warranted. Since signing the MOU, CON has not been required to do a full audit because unaccounted-for water has dropped below 8 percent. Aggressive meter, main and plastic service replacement programs have contributed to maintaining low unaccounted-for water totals.
492 City of Napa Website [http://www.cityofnapa.org/index.php?option=com_content&task=view&id=228&Item- id=314]. 493 CON UWMP, at 6-1 [Exhibit B]. 494 Id. at 6-2 to 6-4. 152 AUGUST 25, 2011
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• BMP 4: Metering with Commodity Rates. The CON water system is fully metered. Excluding standby fire sprinkler services, all existing and new connections require meters and are billed by volume of use. CON mandates that projects with 5,000 square feet or more of landscaping have dedicated irrigation meters.
• BMP 5: Large Landscape Conservation Programs and Incentives. CON funded the installation of computer-based central irrigation systems controlling 25 city parks and 21 Napa Valley Unified School District fields in 2003 and 2004. Employing a weather station, evapotranspiration controllers and flow sensing equipment, the central control systems are expected to save between 130 and 230 AFY by fully optimizing irrigation schedules and addressing leaks.
In related educational activities, CON presents an annual Water-Wise Landscaping Workshop Series and has developed a CD-ROM Water-Wise Gardening in the Napa Valley. CON also mandates that new commercial development with more than 1,000 square feet of landscaping meet CON’s Water Efficient Landscape Guidelines based upon AB 325.
• BMP 6: High-Efficiency Washing Machine Rebate Programs. CON initiated a Residential High-Efficiency Clothes Washer Rebate Program in April 2004 to encourage the purchase of models that use up to 70 percent less water and energy than conventional machines.
• BMP 7: Public Information Programs. CON routinely publicizes its water conservation offerings through water bill messages, press releases and The Reservoir newsletter which premiered in 2003. Water conservation staff host displays at public events such as the Napa-Solano Home & Garden Show and are available to speak to community and business groups.
• BMP 8: School Education Programs. CON water conservation staff were instrumental in the formation of the Environmental Education Coalition of Napa County. The coalition’s Environmental Education Guide is distributed to all area teachers and lists field trips and classroom presentations offered by local agencies and nonprofit organizations. CON offers an interactive water conservation presentation for elementary and middle school classrooms and hosts school groups at its Jamieson Canyon WTP.
• BMP 9: Conservation Programs for Commercial, Industrial and Institutional Accounts. In March 2004, CON began participating in the LightWash Program, offering High- Efficiency Commercial Clothes Washer Rebates to laundromats and other eligible businesses. CON is planning to introduce a Water-Wise Business Survey Program, modeled after the existing program for residential customers under BMP 1.
• BMP 10: Wholesale Agency Assistance Programs. This BMP is not applicable to CON, since it is a retail water provider.
• BMP 11: Conservation Pricing. By employing a uniform volumetric rate structure with no fixed charges, CON meets the definition of conservation pricing in this BMP. Customers are billed based on the quantity of water consumed.
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• BMP 12: Conservation Coordinator. The Water Resources Specialist acts as CON’s Conservation Coordinator and primary contact with the CUWCC. This is a full-time position with some additional duties other than conservation. The Water Resources Specialist holds a Level 1 Water Conservation Practitioner Certification from the California-Nevada section of the American Water Works Association and is assisted in BMP implementation by CON’s Water Conservation Representative.
• BMP 13: Water Waste Prohibition. Originally established with an ordinance in 1992, Napa Municipal Code Chapters 13.10 and 13.12 address prohibitions and limitations on water use during Moderate and Severe Water Shortages as declared by the Napa City Council. These chapters have been inoperative since 1993. A declaration by the City Council would be required to reactivate them.
• BMP 14: Residential ULFT Replacement Programs. Residential customers have participated in the CON Toilet Retrofit Program since 1991. Chapter 13.09 of the Napa Municipal Code requires developers to offset the projected water demand of their new projects, e.g., hotels or housing subdivisions, by reducing demand elsewhere in the city. Since 1991, this water offset has been achieved through replacement of older high-water- use toilets with new ULFTs.
7.2.6.2 Water Shortage Contingency Planning
In the event of a drought, CON would likely adopt a resolution to declare a water shortage emergency, which would implement CON’s Water Shortage Contingency Plan, originally completed in January 1992. In the most recent test of CON’s ability to address a severe water shortage, CON took actions designed to achieve a 20 percent reduction in consumption for the year 1991. The actual reduction in consumption for 1991 was just over 31 percent.495
In response to a water shortage emergency, CON currently has developed a five stage plan. The City’s plan includes no action as well as voluntary and mandatory conservation stages. For each stage, supply shortage triggering levels are established to ensure that the health and safety of CON’s citizens are protected. Either a projected supply shortage or insufficient carryover storage can trigger an action. The specific criteria for triggering the various stages of action are listed in Table 25. As a matter of policy, CON has developed the following priorities for use of available water: (1) health and safety; (2) commercial and industrial; (3) existing landscaping; (4) new demand; and (5) agriculture.496
495 Id. at 7-1. 496 Id. at 7-2. 154 AUGUST 25, 2011
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Table 24. City of Napa Water Shortage Stages of Action Demand Reduction Type of Conservation Stage of Action Goal Program Stage 1 10% No Action Stage 2 15% Voluntary Stage 3 20% Mandatory Stage 4 35% Mandatory Stage 5 50% Mandatory Source: CON UWMP, at 7-2, Table 7-2 [Exhibit B].
Table 25. City of Napa Supply Action Trigger Levels Stage of Action Supply Shortage Carryover Shortage Or insufficient carryover storage and projected Stage 1 Up to 10% reduction supplemental water to provide for 90% of normal supplies for next 2 years Or insufficient carryover storage and projected Stage 2 10-20% reduction supplemental water to provide for 75% of normal supplies for next 2 years Or insufficient carryover storage and projected Stage 3 20-35% reduction supplemental water to provide for 60% of normal supplies for next 2 years Or insufficient carryover storage and projected Stage 4 35-50% reduction supplemental water to provide for 50% of normal supplies for next 2 years Stage 5 More than 50% reduction Source: CON UWMP, at 7-3, Table 7-3 [Exhibit B].
7.2.6.3 Consumption Reduction and Prohibition
During the last major drought to affect Napa from 1987 through 1992, CON adopted Ordinance No. 4277, which prohibited specific acts of water waste. Ordinance No. 4277 was an urgency ordinance addressing the emergency water shortage situation that occurred in 1991. CON eventually replaced the ordinance with Chapters 13.10 and 13.12 of the Napa Municipal Code. They are currently inoperative but could be reactivated by the Napa City Council in the event of a declared shortage.
Chapter 13.10 applies to a “Moderate Water Shortage” and establishes penalties and civil fines for specific acts of water waste. It includes potential restrictions on the amount of water that may be used by a single-family residence, with penalties applied to customers exceeding the amount. Among other regulations, it contains prohibitions on: operation of decorative fountains where water is not recirculated; use of hoses without shut-off nozzles; hosing down pavement
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and driveways; draining and filling of swimming pools; withdrawal of water from hydrants except for fire fighting; serving water to restaurant patrons except on request; and daytime watering of landscapes. Fines for violations range from $50 to $2,500.
Chapter 13.12 identifies more far-reaching restrictions and limitations on water use during a “Severe Water Shortage” of Stage 3 or greater. It includes: allocations of water for individual customers at varying percentages of historical usage; a requirement for CON’s 50 largest users to submit a water conservation plan; and potential establishment of a special block rate structure to address drought-related water purchase and administration expenses. In addition, a wide range of prohibitions intended to minimize water waste are set forth, with a similar range of penalties as in Chapter 13.10.
To reduce short-term demand, an urban water supplier may use any type of consumption limit in its Water Shortage Contingency Plan that is appropriate for its area. Examples of consumption limits that may be used include, but are not limited to, percentage reductions in water allotments, per capita allocations, an increasing block rate schedule for high usage of water with incentives for conservation, or restrictions on specific uses.
As adopted by CON, in Stage 1 there is no required reduction by customers. The City will publicize a Water Shortage Awareness Program and request voluntary conservation by customers. Water supply reductions for Stages 2 through 5 are shown in Table 26.497
Table 26. City of Napa Annual Consumption Limit by Stage and Customer Group
Residential Commercial and Industrial Landscape Agriculture Total Total Demand Reduction Stage 2: Voluntary 8,500 2,550 680 0 11,730 16.2% Stage 3: Mandatory 8,000 2,400 560 0 10,960 21.7% Stage 4: Mandatory 6,500 1,950 440 0 8,890 36.5% Stage 5: Mandatory 5,000 1,500 320 0 6,820 51.3% Source: CON UWMP, at 7-4, Table 7-4 [Exhibit B]. Unless otherwise noted, all figures expressed in AFY.
In normal water supply conditions, production figures are recorded daily. Totals are reported daily to the Water Treatment Facility Supervisor. Totals are reported weekly to the Water Division General Manager and incorporated into the water supply report.498 During a Stage 1, 2 or 3 water shortage, daily production figures are reported to the Supervisor. The Supervisor compares the weekly production to the target weekly production to verify that the demand reduction goal is being met. Weekly reports are forwarded to the Water Division General Manager. Monthly reports are sent to the Napa City Council. If reduction goals are not met, the Water Division General Manager will notify the City Council so that corrective action can be
497 Id. at 7-3 to 7-4. 498 Id. at 7-5. 156 AUGUST 25, 2011
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taken.499 During a Stage 4 or 5 water shortage, the procedure listed above will be followed, with the addition of a daily production report to the Water Division General Manager.500
7.3 Water Supplies
CON meets its current demands by supplying water from three major sources: (1) Milliken Reservoir; (2) Lake Hennessey; and (3) imported SWP water delivered through the North Bay Aqueduct.501 The first three subsections below address each of these supplies. Additional subsections address potential future water supplies being explored by CON and the city’s projection of total water supplies available.
7.3.1 Milliken Reservoir
CON began offering water service in 1923, coinciding with the construction of Milliken Dam, which allowed storage of water from Milliken Creek, a tributary of the Napa River.502 The resulting Milliken Reservoir served as CON’s sole water source until Lake Hennessey was created in 1946, as discussed in Section 7.3.2. Milliken Dam, located approximately five miles northeast of CON, is now a minor, secondary source of supply used only in the high-demand summer period when turbidity levels in the reservoir can be effectively treated at the Milliken Water Treatment Plant.503
The Milliken Creek watershed covers an area of roughly 6,000 acres. The City’s water rights to Milliken Reservoir are secured through a license with the SWRCB, which authorizes CON to divert and store up to 2,350 AFY from Milliken Creek for beneficial use. Milliken Reservoir’s approximate storage capacity originally was 1,980 AF, smaller than its average annual inflow of 3,656 AF. The current storage capacity of Milliken Reservoir is limited to 1,390 AF because of five holes cored through the dam to permanently lower the water surface elevation and address seismic stability concerns by the State Division of Safety of Dams.
For purposes of CON UWMP, a single dry year is defined as the historical year with the lowest runoff since 1903, which occurred in this case in 1977. Multiple dry years are defined as the three consecutive historical years with the lowest average runoff since 1903, which occurred in the extended drought period of 1987 through 1992.504 The CON UWMP and 2050 Study both assume a maximum annual yield for Milliken Reservoir of 700 AF in all but critical single-dry years, when the reservoir is expected to yield 400 AF.505 In order to augment water supplies during dry years, CON’s operational plans include the release from storage of 100 AF during a single dry year and 33 AFY during multiple dry years.506 Including such releases, the expected yields from Milliken Reservoir in normal, multiple dry and single dry years are summarized in Table 27.
499 Id. 500 Id. 501 Id. at 3-1. See Gasser FEIR, at 4.12-2. 502 CON UWMP, at 3-3 [Exhibit B]; 2050 Study, Tech. Memo 4, at 12 [Exhibit D]. See Gasser FEIR, at 4.12-2. 503 CON UWMP, at 3-3 [Exhibit B]; 2050 Study, Tech. Memo 4, at 12 [Exhibit D]. See Gasser FEIR, at 4.12-2. 504 Id. at 4-1, 4-2. 505 CON UWMP, at 3-3 to 3-4, 4-4 [Exhibit B]. 506 Id. at 4-4. AUGUST 25, 2011 157
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Table 27. Milliken Reservoir Yield Normal Years Multiple Dry Years Single Dry Years Annual Yield 700 700 400 Releases from Storage 0 33 100 Total Yield 700 733 500 Source: CON UWMP, at 3-4, 4-4 [Exhibit B]. All figures expressed in AFY.
The City does not take raw water directly from the reservoir. Instead, the raw water is released into Milliken Creek by a manually operated valve system at the base of the dam. Two miles downstream, a diversion dam directs water into a 16-inch diameter above ground raw water line. That line then runs approximately one mile to the Milliken Water Treatment Plant, which was constructed in 1976 and has a treatment capacity of 4.0 MGD.507 It is a direct filtration plant, and treated water is stored in a 2.0 million gallon clearwell tank located above the treatment plant site. Treated water is delivered to CON’s water distribution system via the approximately three-mile-long Milliken Transmission Line.
7.3.2 Lake Hennessey
Lake Hennessey is the major local water source for the City of Napa and is located approximately 13 miles north of the city. Lake Hennessey was formed in 1946, after subdivision development in the 1940s strained the older Milliken Reservoir—CON’s previous single water source for more than twenty years.508 In order to ease demands on Milliken Reservoir, CON constructed Conn Dam, allowing storage of water from Conn Creek. Lake Hennessey was the resulting reservoir, and served as CON’s primary source for the next several decades until supplemented by SWP water in the 1960s.509
The City owns the water rights to Lake Hennessey through a license with the SWRCB. The license authorizes CON to divert and store up to 30,500 AFY from Conn Creek for beneficial use. Lake Hennessey has an approximate storage capacity of 31,000 AF, much greater than its average annual inflow of 19,692 AF.510
The average yield of Lake Hennessey is 17,500 AFY. For water supply planning purposes, CON uses 17,500 AFY as the amount available during normal years, 10,417 AFY as the yield during multiple dry years, and 5,000 AFY as the yield during single dry years.511 In order to augment water supplies during dry years, CON’s operational plans include the release of 6,500 AF during a single dry year and 1,300 AFY during multiple dry years.512 Including such releases, the expected yields from Lake Hennessey in normal, multiple dry and single dry years are summarized in Table 28.
507 Id. at 3-3, 3-4. 508 Id. at 3-1; 2050 Study, Tech. Memo 4, at 11 [Exhibit D]. See Gasser FEIR, at 4.12-2. 509 CON UWMP, at 3-1 [Exhibit B]; 2050 Study, Tech. Memo 4, at 11 [Exhibit D]. 510 CON UWMP, at 3-1 [Exhibit B]; 2050 Study, Tech. Memo 4, at 11 [Exhibit D]. See Gasser FEIR, at 4.12-2. 511 CON UWMP, at 3-1, 3-3, 4-4 [Exhibit B]; 2050 Study, Tech. Memo 4, at 11 [Exhibit D]. See Gasser FEIR, at 4.12-2. 512 CON UWMP, at 4-4 [Exhibit B]. 158 AUGUST 25, 2011
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Table 28. Lake Hennessey Yield Normal Years Multiple Dry Years Single Dry Years Annual Yield 17,500 10,417 5,000 Releases from Storage 0 1,300 6,500 Total Yield 17,500 11,717 11,500 Source: CON UWMP, at 3-3, 4-4 [Exhibit B]. All figures expressed in AFY.
Raw water from Lake Hennessey is treated at CON’s Hennessey Water Treatment Plant, which began operation in 1981 and has a nominal treatment capacity of 20 MGD. This facility provides complete conventional water treatment, and treated water from the plant is conveyed into a buried 5.0 million gallon concrete clearwell tank on site.513 This treated water is then delivered to CON’s distribution system through the 36-inch diameter Conn Transmission Main, which is approximately 20 miles long and runs parallel to Conn Creek, Highway 128 and Highway 29 before it eventually meets the Jamieson Line in northwest Napa.514
7.3.3 State Water Project
7.3.3.1 Basic Description of the SWP
In 1966, 20 years after the addition of Lake Hennessey and more than 40 years after the creation of Milliken Reservoir, CON added a third source of supply by sub-contracting with the Napa County Flood Control & Water Conservation District (“NCFCWD”) for imported surface water from the SWP.
The SWP is one of the largest water collection and distribution systems in California. It collects water at Lake Oroville on the Feather River in northern California and conveys it to approximately 29 customers, or contractors, located in northern, central and southern California through an extensive network of aqueducts. All SWP water is delivered according to long-term contracts negotiated between DWR, which owns and operates the SWP, and its contractors. NCFCWD is the designated contractor for Napa County, and NCFCWD has, in turn, subcontracted for delivery of SWP water to several entities including CON.
As described in Section 5.5.1, the NBA is a 27-mile long, pressurized, underground pipeline. The SWP diverts water from the Sacramento-San Joaquin Delta at the Barker Slough Pumping Plant east of Fairfield and conveys it approximately 21 miles via the NBA to Cordelia Forebay to serve contractors in both Napa and Solano Counties. From Cordelia Forebay, SWP water is pumped another six miles to the Napa Turnout Reservoir, which is a 7 million gallon raw water storage tank for the Jamieson Canyon WTP. The majority of the capacity of the NBA to this point is reserved for use by CON.515 The Barker Slough Pumping Plant has a design flow
513 Id. at 3-3. 514 Id. 515 Id. at 3-4. AUGUST 25, 2011 159
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capacity of 224 cfs to lift water from Barker Slough into the North Bay Aqueduct; however to date, the maximum flow of the North Bay Aqueduct is rated at approximately 140 cfs.516
The original 1966 SWP subcontract between NCFCWD and CON provided the latter with gradually increasing annual allotments of NCFCWD’s allotted SWP water, known as “Table A” entitlements, reaching a maximum of 12,500 AF by 1990. The agreement was modified in 1982, and the modification reduced CON’s short-term Table A entitlement, but increased its final overall entitlement to 18,800 AFY by 2021. In 1999, CON negotiated an acceleration of this entitlement schedule, helping to increase near-term supply options.
These amounts represent the maximum annual yields of Table A water. Actual deliveries are determined by DWR depending on each year’s hydrologic conditions, including rainfall, size of snowpack, runoff, water in storage and pumping capacity in the Delta. A full 100 percent of the entitlement would typically only be available during relatively wet years. The current SWP contract is due to expire in 2035, but there is no reason to believe the contracts would not be extended for additional terms into the indefinite future.
In 2000, CON obtained an additional 1,000 AFY of SWP water in a transfer agreement between NCFCWD and the Kern County Water Agency (“KCWA”). Negotiated on behalf of five cities in Napa County, the agreement established terms for the permanent purchase of 4,025 AF of annual SWP Table A entitlement from KCWA. The City purchased the largest share of this total at 1,000 AFY.517
In 2006, CON acquired an additional 1,000 AFY of the KCWA entitlement from the City of St. Helena, as described in Section 7.2.4. The acquisition agreement provided, however, that St. Helena could request delivery to itself of between 200 and 400 AFY of that SWP supply, so that the amount of additional SWP water retained by CON was between 600 and 800 AFY. In 2009, the agreement was amended so that St. Helena can request delivery of between 400 and 800 AFY, with CON retaining between 200 and 600 AFY. For the conservative planning purposes of this WSA, 200 AFY are added to CON’s SWP supplies.
In 2009, CON executed a Water Transfer Agreement with the Town of Yountville by which Yountville assigned to CON its 1,100 AFY Table A entitlement of SWP water, along with 0.4 cfs of North Bay Aqueduct capacity. In exchange, CON agreed to deliver water as needed to the Town of Yountville for fire flow and emergency water needs, not to exceed 25 AFY. The total amount of SWP water available to CON, including the amounts purchased from KCWA, City of St. Helena and the Town of Yountville, is shown in Table 29.
516 City of Napa, Jamieson Canyon Water Treatment Plant Improvements Project, Draft Environmental Impact Report, at 3.7-1 (“Jamieson Canyon EIR”) [available from City of Napa]. 517 CON UWMP, at 3-5 [Exhibit B]. 160 AUGUST 25, 2011
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Table 29. City of Napa SWP Table A Entitlement Schedule Table A KCWA St. Helena Yountville Year Entitlement Purchase Purchase† Purchase Total 2005 12,850 1,000 0 0 13,850 2006 13,100 1,000 600 0 14,700 2007 13,350 1,000 600 0 14,950 2008 13,600 1,000 600 0 15,200 2009 13,850 1,000 200 1,100 16,150 2010 14,100 1,000 200 1,100 16,400 2011 14,350 1,000 200 1,100 16,650 2012 14,600 1,000 200 1,100 16,900 2013 14,800 1,000 200 1,100 17,100 2014 15,100 1,000 200 1,100 17,400 2015 15,700 1,000 200 1,100 18,000 2016 16,300 1,000 200 1,100 18,600 2017 16,900 1,000 200 1,100 19,200 2018 17,500 1,000 200 1,100 19,800 2019 18,100 1,000 200 1,100 20,400 2020 18,700 1,000 200 1,100 21,000 2021 18,800 1,000 200 1,100 21,100 Following Years 18,800 1,000 200 1,100 21,100 Source: CON UWMP, at 3-5 [Exhibit B]. All figures expressed in AF. † Minimum net St. Helena purchase, after taking into account maximum deliveries to St. Helena.
7.3.3.2 Additional SWP Supplies
In addition to the water to which the NCFCWD is entitled under Table A of its contract, the SWP makes certain other water available on a year-by-year basis. As the largest subcontractor with NCFCWD, CON has the ability to acquire some of that additional water as needed.
First, “Carryover Water” is water from a previous year’s entitlement that was available for use, but exceeded demands, and was therefore stored for use in subsequent years. Carryover water is stored in San Luis Reservoir and if San Luis Reservoir spills, the carryover water is considered the first water to be lost. Historically, CON has typically used carryover water in the first few months of the year before San Luis Reservoir has spilled and ended the possibility of carryover water. In the projected future, however, due to pumping restrictions in the south Delta that are discussed in detail in Section 7.3.3.5, it is expected that San Luis Reservoir will not spill until later in the year, or potentially not at all during some years. Thus, an increased amount of carryover water will likely be available to NCFCWD and CON in future, and CON plans to
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make use of that supply.518 This is not considered a new supply, but is a method for shifting SWP water from one year to another. The overall amount of carryover water is limited, varying between 25 and 50 percent of Table A entitlement depending on the allocation percentage for that year, but is significant. For example, the lowest quantity of carryover water available to CON would be 5,275 AFY in 2020 and later years.519 Carryover water is not available in every year.
Second, “Article 21” water is an interruptible surplus SWP supply CON has used in the past and plans to continue using in future. Article 21 of the SWP contract allows for the purchase of surplus water beyond the Table A quantities, provided that the contractor can take delivery during the wet season without affecting Table A deliveries to other contractors. NCFCWD uses an annual delivery schedule that maximizes CON’s use of Article 21 water following consumption of carryover water.520 Again, based on the pumping restrictions in effect for the south Delta, it is expected that Article 21 water will generally be more available in future than it has been historically for contractors that take water from the Barker Slough Pumping Plant and North Bay Aqueduct. Both NCFCWD and CON can be expected to utilize increased amounts of Article 21 water when it is available.
Third, each year DWR decides whether or not to operate a dry year purchase program based on Article 56 of the SWP contract. A “Turn-Back Pool” may be established with water form agencies not using their full entitlement distributed to other agencies requesting additional supplies. This is not considered a reliable long-term source due to its unpredictable nature.
Finally, in rare circumstances DWR helps to facilitate voluntary transactions between water rights holders in the Sacramento and Feather River watersheds in northern California and potential water users throughout the state, including conveyance through SWP facilities. In 2009, DWR has established the Drought Water Bank for this purpose, and NCFCWD has executed a purchase agreement under the program for up to 2,950 AF, of which 1,780 AF are for CON. Like the Turn Back Pool, this is not considered a reliable long-term source due to its occasional unpredictable nature. However, programs such as the Drought Water Bank help to mitigate the uncertainties of the basic SWP Table A entitlements held by various contractors, including NCFCWD and, derivatively, CON.
7.3.3.3 Jamieson Canyon WTP
All of CON’s SWP water is treated at the Jamieson Canyon WTP. Constructed in 1968, the plant was upgraded in 1988 to provide a rated treatment capacity at 12 MGD, and can currently be run at 15 MGD if needed.521 Treated water is stored in a 5.0 million gallon clearwell tank on site, and the Jamieson Transmission Line delivers the potable water to CON. The Jamieson Transmission Line consists of a 42-inch diameter line that runs parallel to Jamieson Canyon
518 Id. at 3-6. 519 See Amendment No. 18 (The Monterey Amendment) to Water Supply Contract Between the State of California Department of Water Resources and Napa County Flood Control and Water Conservation District, at § 27, p. 53 (February 1, 1996) [http://www.water.ca.gov/swpao/docs/wsc/NCFC_O_C.pdf]. This 5,225 AFY figure is calculated by multiplying 20,900 AFY by 25 percent. 520 CON UWMP, at 3-6 [Exhibit B]. 521 Id. at 3-5. 162 AUGUST 25, 2011
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Road to Highway 29, which then splits into 36-inch and 24-inch lines near the intersection of Highways 29 and 221 as it joins the rest of the distribution system.
The Jamieson Canyon WTP produces the majority of CON’s water during the winter.522 In the spring through fall months when demand is higher, production at the Jamieson Canyon WTP is used to augment supplies from the Milliken and Hennessey Water Treatment Plants. Currently, the Jamieson Canyon WTP operates at seasonal peak raw water flow rates as high as 16 MGD, and as a result, CON’s current maximum flow rate exceeds the plant’s design capacity.523
The Jamieson Canyon WTP Improvements Project, first identified in CON’s 1997 Master Plan, will increase the treatment capacity of the plant from 12 MGD to approximately 20 MGD, and a hydraulic peak hour treatment capacity of 24 MGD.524 Currently, with the Jamieson facility’s treatment capacity of 12 MGD (peak 15 MGD), CON is not able to treat all of its entitled water supplies from the SWP.525 The planned plant capacity expansion will allow CON to utilize and treat a greater portion of its allotment of SWP water supplies that are delivered through the North Bay Aqueduct.526 This will enable CON to meet current and projected demands based on General Plan build-out in 2020.527 The project is currently under construction and is expected to be completed in January 2011.528
The improvements at the plant primarily consist of internal plant modifications, including the repair and replacement of existing facilities and the addition of new facilities. Upon completion of the project, the day-to-day operations of the Hennessey and Milliken Water Treatment Plants are to be reduced and will come on-line as necessary to supply water during high demand periods.529
7.3.3.4 State Water Project Supply Reliability
As noted above, Table A entitlements represent the maximum water available to SWP contractors and subcontractors, rather than the reliable annual yield of the project. The ability of the SWP to deliver water to its contractors in any given year depends on a number of factors, including rainfall, size of snowpack, runoff, water in storage and pumping capacity in the Sacramento River Delta. The actual delivery varies from year to year and is described as a percentage of the contractual entitlement. For CON, annual SWP deliveries are a percentage of its basic Table A deliveries plus KCWA and Yountville water. Deliveries will be reduced in normal, single-dry and multiple-dry years.
In order to estimate the reliability of SWP supplies, CON UWMP and 2050 Study employ data from the SWP Delivery Reliability Report 2002, published by DWR in 2003. In August of 2008, DWR issued its 2007 Reliability Report containing updated reliability assessments, which are
522 Jamieson Canyon EIR, at 2-3. 523 Id. 524 CON UWMP, at 3-6 [Exhibit B]; Jamieson Canyon EIR, at ES-1. 525 CON UWMP, at 3-6 [Exhibit B]. 526 Jamieson Canyon EIR, at ES-1. 527 Id. at 3.5-5. 528 City of Napa Website [http://www.cityofnapa.org/index.php?option=com_content&task=view&id=367&Item- id=465]. 529 Jamieson Canyon EIR, at ES-2. AUGUST 25, 2011 163
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used for purposes of this WSA.530 DWR uses a computer model of the SWP system to determine the reliability of its water deliveries,531 and continues to evaluate the various issues affecting SWP exports from the Delta and how those issues may affect the long-term availability and reliability of SWP deliveries to contractors. DWR’s 2007 report is based on analysis of recent institutional and environmental limitations, including water quality issues, fishery protections, export curtailments and other requirements under SWRCB Water Rights Decision 1641, the Vernalis Adaptive Management Plan (“VAMP”), and Delta export restrictions to protect fish species such as those imposed in the Delta smelt and salmonid cases discussed below.
According to the 2007 report, the long-term average delivery of contractual SWP Table A supplies is expected to range from 63 percent under current conditions to between 66 and 69 percent under future (2027) conditions.532 Within that long-term average, SWP Table A deliveries can range from 6 percent (single dry year) to 90 percent of contractual amounts under current conditions533 and from 6 to 7 percent (single dry year) to 100 percent of contractual amounts under future (2027) conditions.534 The analyses provided in the DWR report are based upon 82 years of historical records (1922-2003) for rainfall and runoff that have been adjusted to reflect the current and future levels of development in the sources areas by analyzing land use patterns and projecting future land and water uses.535
Table 30. State Water Project Reliability Assessments (2002 and 2007) 2002 Reliability Report 2007 Reliability Report
Water Year Type Projected SWP Delivery Base Years Probability of Exceedence Projected SWP Delivery Base Years Probability of Exceedence
Normal Year 76% 1922-1994 60% 66-69% 1922-2003 55% Multiple Dry Year 40% 1987-1992 85% 33-35% 1987-1992 88% Single Dry Year 20% 1977 100% 7% 1977 95% Source: CON UWMP, at 4-1, 4-2 [Exhibit B]; SWP Reliability Report, at 56-62.
DWR’s 2007 single dry year delivery numbers differ significantly from the 2002 study used as the basis for the CON UWMP and 2050 Study. Table 30 summarizes the SWP reliability data
530 California Department of Water Resources, The State Water Project Delivery Reliability Report 2007 (August 2008) (“SWP Reliability Report”) [http://baydeltaoffice.water.ca.gov/swpreliability/Final_DRR_2007_011309.pdf]. 531 The DWR model is called CalSim-II, and its use as a water supply planning tool has been upheld by the courts. See Pacific Coast Federation of Fishermen’s Associations v. Gutierrez, 606 F.Supp.2d 1122, 1191 (2008); California Water Impact Network v. Newhall County Water District, Case No. B203781, slip opin. at 21-25 (2nd App. Dist. May 13, 2009) (unpublished). 532 SWP Reliability Report, at 44-45, 51-52, 55-56, 78. 533 Id. at 44 534 Id. at 51, 55-56. DWR uses the same definition of normal, multiple dry and single dry years as is used in the CON UWMP. Id. at 62, 79-80. 535 Id. at 20. 164 AUGUST 25, 2011
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analyzed by the CON UWMP and the 2050 Study versus the 2007 SWP Delivery Reliability Report for normal, multiple dry and single dry years. As an example, the final DWR allocation of SWP deliveries for 2009 sets annual Table A deliveries at 40 percent, reflecting the current multiple dry year hydrologic conditions.536
Because CON’s SWP Table A entitlements are scheduled to increase until 2021, the estimated actual SWP deliveries for these three hydrologic scenarios will also increase through that time period. Table 31 estimates SWP deliveries through 2030 by applying the delivery percentages in Table 30 to the escalating entitlements in Table 29, including the KCWA, St. Helena and Yountville purchases. Under the SWP Reliability Report, in 2021 and beyond CON can expect between 13,926 to 14,559 AF from the SWP in normal years, between 6,963 and 7,385 AF during multiple-dry year periods, and only about 1,477 AF in a critical single-dry year.537 None of these deliveries will be limited by CON’s North Bay Aqueduct conveyance capacity of 18,800 AFY. These estimates assume no additional water from the St. Helena supply, carryover water, Article 21 water or any other supplemental categories of supply and thus are conservative estimates of the amount of SWP water that will be available to CON.
Table 31. City of Napa Projected SWP Deliveries Table A Normal Year Multiple Dry Year Single Dry Year Entitlement (Min/Max) (Min/Max) Year 2010 16,400 10,824 11,316 5,412 5,740 1,148 2011 16,650 10,989 11,489 5,495 5,828 1,166 2012 16,900 11,154 11,661 5,577 5,915 1,183 2013 17,100 11,286 11,799 5,643 5,985 1,197 2014 17,400 11,484 12,006 5,742 6,090 1,218 2015 18,000 11,880 12,420 5,940 6,300 1,260 2016 18,600 12,276 12,834 6,138 6,510 1,302 2017 19,200 12,672 13,248 6,336 6,720 1,344 2018 19,800 13,068 13,662 6,534 6,930 1,386 2019 20,400 13,464 14,076 6,732 7,140 1,428 2020 21,000 13,860 14,490 6,930 7,350 1,470 2021 21,100 13,926 14,559 6,963 7,385 1,477 Following 21,100 13,926 14,559 6,963 7,385 1,477 Source: CON UWMP, at 4-3 [Exhibit B]; 2050 Study, Tech. Memo 4, at 18 [Exhibit D]; SWP Reliability Report, at 56-62. All figures expressed in AF.
536 California Department of Water Resources, Notice to State Water Project Contractors: 09-07 (May 20, 2009) [http://www.water.ca.gov/swpao/docs/notices/09-07.pdf]. 537 CON UWMP, at 4-2 [Exhibit B]. AUGUST 25, 2011 165
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7.3.3.5 Further SWP Reliability Factors
Following issuance of the 2002 SWP Reliability Report, CON UWMP and 2050 Study, SWP supplies have been challenged by various environmental litigation concerning diversions from the Sacramento River Delta, as discussed in Section 5.4 of this WSA. Conveyance of water through the Delta can present challenges for SWP supplies due to water quality and environmental issues that can affect pumping operations. Risks to this supply also include potential levee failure. The risks and actions being taken by DWR to avoid or mitigate these risks were previously described in Section 5.4 and its subsections. The factors discussed previously affecting SWP reliability and supplies impact CON, as a purchaser of SWP water, as well as for Project supplies.
7.3.4 Other Potential Water Sources
In addition to its existing water sources, CON has studied the potential for several new supplies, as discussed in the following subsections.
7.3.4.1 Dry Year Supplies
The top project recommendation of the 2050 Study is for the Napa County water agencies to take advantage of North Bay Aqueduct conveyance capacity by importing dry year supplies from outside the County. This has been called the “Fill the Pipe” option, which would require negotiation of one or more long-term transfer agreements for reliable dry year supplies from water rights holders such as the numerous Sacramento River users.538 The City has had discussions with several entities about the purchase of such dry year supplies, but has not yet entered into any definitive agreements. It is unknown if and when such agreements may be entered into, or how much or when water would be made available to CON based on such agreements. Thus, this WSA does not include such supplies in its analysis, even though they may become available at an indefinite point in future.
7.3.4.2 Groundwater
CON currently relies exclusively on surface water from local sources and imported water from the SWP. The 2050 Study identified several alternatives for using groundwater in future. First, CON could divert excess water available from the SWP and North Bay Aqueduct during wet periods and store it using aquifer storage and recovery (“ASR”) wells in Solano County. Second, CON could use new or existing wells in the vicinity of CON, either for treatment and distribution in the potable water system, or for direct use for non-potable purposes such as irrigation of schools and parks. Use of groundwater for potable purposes might be as a dry year supply only.539
Third, CON has recognized that “[t]here are a number of large wells on the former Napa Pipe industrial site. If this site is developed in the future, the existing wells could potentially meet the site’s water demands.”540 Thus, CON has considered an alternative in which groundwater underlying the Project site would be pumped in order to offset the demands that the Project
538 CON UWMP, at 3-7 [Exhibit B]. 539 Id. 540 Id. 166 AUGUST 25, 2011
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would add to CON’s water service obligations. For purposes of this WSA, use of local groundwater from beneath the Project site is not considered to be part of CON water supplies, but as an independent supply pursuant to Section 4. This is consistent with the water rights of the Project site being part and parcel of ownership of the Project site land by NRP.
7.3.4.3 Recycled and Desalinated Water
The City supplies only potable water to its customers, and recycled water deliveries in the area are handled by NSD.541 Because the expanded use of recycled water from NSD within CON’s water service area reduces the demands on City water supplies, CON considers use of recycled water to be a method of demand management rather than a supplemental supply.542
The City has evaluated the possibility of using desalinated water as a supplemental source and has determined not to pursue such a supply at this time.543
7.3.5 Total Supply Projections
Table 32 shows total available water supplies for CON from 2010 through 2030. The table includes quantities available from known sources and assumes maximum annual yield without storage withdrawals for the local reservoirs and full entitlements for SWP water.
Table 32. City of Napa Total Water Supplies (2010-2030) Water Supply Source 2005 2010 2015 2020 2025 2030 Lake Hennessey 17,500 17,500 17,500 17,500 17,500 17,500 Milliken Reservoir 700 700 700 700 700 700 State Water Project 13,850 16,400 18,000 21,000 21,100 21,100 Total 32,050 34,600 36,200 39,200 39,300 39,300 Source: CON UWMP, at 3-8, Table 3-4 [Exhibit B]; 2050 Study, Tech. Memo 6, at A-2 [Exhibit D]. All figures in AFY.
In contrast to Table 32, which assumes maximum annual yields for local reservoirs and full entitlements for SWP water, the following analysis examines the reliability of City water supplies in different hydrologic year types. It is important to note that water year types do not necessarily coincide between local reservoirs and the SWP. As the CON UWMP notes, a normal rainfall year in the Milliken Reservoir or Lake Hennessey watersheds may occur the same year as a dry year for the SWP, or vice versa.544 Nevertheless, this WSA like the CON UWMP evaluates the water supplies available from each source during parallel normal, multiple dry and single dry years in order to test the availability of water during widespread drought conditions. The results of this analysis are shown in Table 33. The figures in Table 33 differ from prior published City water planning documents based on the subsequent changes in SWP reliability.
541 See Section 6.1.5 of this WSA regarding the relationship between NSD and the City. 542 CON UWMP, at 3-7 [Exhibit B]. 543 Id. 544 Id. at 4-3. AUGUST 25, 2011 167
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Table 33. City of Napa Water Supplies Under Various Hydrologic Conditions (2010-2030) Milliken Lake Year Condition Reservoir Hennessey SWP Total Normal 700 17,500 10,824 29,024 2010 Multiple Dry 733 11,717 5,412 17,862 Single Dry 500 11,500 1,148 13,148 Normal 700 17,500 11,880 30,080 2015 Multiple Dry 733 11,717 5,940 18,390 Single Dry 500 11,500 1,260 13,260 Normal 700 17,500 13,860 32,060 2020 Multiple Dry 733 11,717 6,930 19,380 Single Dry 500 11,500 1,470 13,470 Normal 700 17,500 13,926 32,126 2025 Multiple Dry 733 11,717 6,963 19,413 Single Dry 500 11,500 1,477 13,477 Normal 700 17,500 13,926 32,126 2030 Multiple Dry 733 11,717 6,963 19,413 Single Dry 500 11,500 1,477 13,477
7.4 City Water Supplies v. Demands
Conclusions about the reliability of CON water supplies to serve existing and future water demands, as well as the projected demands of the Project, require a comparison of water supplies and demands across hydrologic year types for the first 20 years of the Project. Table 34 compares total water supplies and demands of CON, and calculates the amount of surplus or deficit in those water supplies for the defined year types, both with and without the Project. Consistent with the phasing discussed in Section 3.5 of this WSA, water demands associated with the Project are 241 AFY starting in 2010 for Phase 1 and a cumulative 620 AFY starting in 2015 for the completed Project.
As shown in Table 34, CON has a surplus of water under normal and multiple dry years, both with and without the Project. Those surpluses range from 16 to 77 percent without the Project, and from 12 to 74 percent with the Project. Thus, CON’s total projected water supplies available during normal and multiple dry water years during a 20-year projection will meet the projected water demand associated with the Project, in addition to CON’s existing and planned future uses, including agricultural and manufacturing uses.545
545 See CAL. WATER CODE § 10910(c)(3). 168 AUGUST 25, 2011
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Table 34. City of Napa Water Supplies and Demands (2010-2030) No Project Demands With Project Demands
Year Condition Total Supplies Demands Surplus (Deficit) Surplus (Deficit) Percentage Demands Surplus (Deficit) Surplus (Deficit) Percentage Normal 29,024 16,395 12,629 77 16,635 12,389 74 2010 Multiple Dry 17,862 13,936 3,926 28 14,177 3,685 26 Single Dry 13,148 13,936 (788) (6) 14,177 (1,029) (7) Normal 30,080 17,489 12,591 72 18,109 11,971 66 2015 Multiple Dry 18,390 14,866 3,524 24 15,486 2,904 19 Single Dry 13,260 14,866 (1,606) (11) 15,486 (2,226) (14) Normal 32,060 18,798 13,262 71 19,418 12,642 65 2020 Multiple Dry 19,380 15,978 3,402 21 16,598 2,782 17 Single Dry 13,470 15,978 (2,508) (16) 16,598 (3,128) (19) Normal 32,126 19,243 12,883 67 19,863 12,263 62 2025 Multiple Dry 19,413 16,357 3,056 19 16,977 2,436 14 Single Dry 13,477 16,357 (2,880) (18) 16,977 (3,500) (21) Normal 32,126 19,699 12,427 63 20,319 11,807 58 2030 Multiple Dry 19,413 16,744 2,669 16 17,364 2,049 12 Single Dry 13,477 16,744 (3,267) (20) 17,364 (3,887) (22)
During single dry years, as defined by DWR in its SWP Reliability Report and shown in Table 34, CON is currently projected to experience water supply deficits over the next 20 years, both with and without the Project. The effect of the Project would be to increase the amount of the deficit by the demands of the Project, i.e., 620 AFY. Without the Project, City water supplies are expected to be in deficit during single dry years ranging from 6 to 20 percent, while with the Project deficits will range from 7 to 22 percent.
Based on the total demands in Table 34 and the water supplies from Milliken Reservoir and Lake Hennessey as listed in Table 33, CON would need to receive 4,744 AF from the SWP in order to balance water supplies and demands without the Project, which equals a 22.5 percent allocation of its SWP entitlement. With the Project, CON would need to receive 5,364 AF, which is 25.4 percent of its SWP entitlement. According to the SWP Reliability Report, the SWP will exceed those amounts with the same frequency, 93 percent.546 Therefore, during 93 percent of all years (equal to approximately 13 out of every 14 years), CON will experience a water supply surplus either with or without the Project, while it will experience a deficit during the remaining 7
546 SWP Reliability Report, at 79-80, Table B.3. AUGUST 25, 2011 169
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percent of all years (equal to approximately one of out every 14 years). Provision of water service to the Project by CON does not change the percentage of years in which surplus (or deficit) conditions exist; the impact of the Project is merely to reduce the size of the surplus, or increase the size of the deficit, by the amount of Project water demands.
Consistent with the findings of this WSA, the CON UWMP from 2005 found that CON water supplies are in surplus during normal and multiple dry years, but in deficit during single dry years.547 Based on the reduction in SWP deliveries in the 2007 SWP Reliability Report as compared to the 2002 version of that report, the deficits in City water supplies during single dry years are now projected to be higher than in the CON UWMP. In the CON UWMP, the deficits were projected to range from 0.2 to 5 percent, while in this WSA the deficits are projected to range from 6 to 22 percent, as explained above.
In the CON UWMP, CON made the following conclusions about its water supplies during single dry years:
With the assumptions used in the 2050 Study and [CON UWMP], [CON] would experience water shortages in single-dry years occurring in 2020 and beyond. As noted earlier, many of these assumptions have been very conservative for planning purposes, such as the ABAG population in the RUL, the starting per capita demand of 180 gpcd, and the 10% unaccounted-for water. More favorable numbers in any of these categories could almost eliminate these projected shortfalls of 0.2% to 5%. Also, long- term BMP implementation and the additional recycled water users proposed in the draft NSD Strategic Plan could reduce City demand enough to erase these deficits. In the worst case and if no imported dry year supplies were obtained, Stage 3 actions in the Water Shortage Contingency Plan could be needed.548
The projections of City water supplies and demands in this WSA are based on the same conservative assumptions as the CON UWMP. Thus, the deficits projected for single dry years are likely to be overestimated. As noted by CON, long-term implementation of water conservation measures, as well as the shifting of certain water demands from potable to recycled water supplies, are likely to reduce total water demands below the projections in this WSA. Also, CON has had success in the past in temporarily reducing water demands based on supply constrictions. In 1991, CON took actions designed to achieve a 20 percent reduction in demands, and the result was a reduction by just over 31 percent.549 Such a 31 percent reduction in future would be sufficient to eliminate the deficit in all projected years, including the water demands of the Project.
In addition to the demand management methods suggested by CON for correcting its supply deficit in single dry years, CON could also increase its supplies in ways that were excluded from the figures in Table 33. For example, CON has access to additional water based on the St.
547 CON UWMP, at 9-1 [Exhibit B]. 548 Id. at 9-1 to 9-2. 549 Id. at 7-1. 170 AUGUST 25, 2011
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Helena purchase and from the SWP in certain years based on carryover of entitlement water from prior years, purchase of Article 21 water, and purchase of water from special dry year supply programs.
The calculations of City water supplies and demands above assume that St. Helena will take delivery of the maximum quantities to which it is entitled in its agreement with CON, i.e., 800 AFY. The amount requested by St. Helena could be as low as 400 AFY, which would make an additional 400 AFY of Table A entitlement available to CON to augment its own supplies, which would mean an additional 28 AFY of water for CON during a single dry year.
The City typically uses carryover water in the first few months of each water year and plans to continue to do so, likely with the ability to acquire greater carryover water in future than historically was possible.550 In normal and multiple dry years, which occur with a 93 percent frequency, CON has a water supply surplus, so in those years CON does not use all of its supply and can carryover water into the following year or years. The City can carry over at least 5,275 AFY of its Table A entitlement as long as San Luis Reservoir does not spill. In single dry years, San Luis Reservoir is less likely to spill than during other times. A carryover of 5,275 AFY would more than cover the projected deficit in City water supplies, which has a maximum projection of 3,887 AFY, either with or without the Project.
The City also regularly purchases water under Article 21, which allows CON to acquire additional water supplies during the wet season. The City can make use of Article 21 water by relying exclusively on imported water supplies and keeping its local reservoirs full. The City plans to continue using Article 21 water whenever possible.551
The City also has access to special dry year water purchase programs administered by DWR. For example, in 2009 DWR has planned and executed a Drought Water Bank, under which CON has purchased an additional 1,780 AF of water. The Drought Water Bank has acquired water supplies from various water rights holders in the Sacramento River watershed based on releases of water from long-term storage, idling of irrigated agricultural lands and the substitution of groundwater for Sacramento River water by some water users. NCFCWD has executed a contract with DWR to purchase a portion of the water that has been made available, and CON has contracted with NCFCWD for a portion of the transferred amount.552 It is expected that DWR will seek to operate similar dry year supply programs in future, and NCFCWD and CON will be able to participate on the same basis as other SWP contractors.
In addition to programs operated by DWR, CON and NCFCWD have expressed interest in obtaining additional water supplies in dry years on their own. Thus, CON acquired the Table A entitlement of the Town of Yountville earlier this year, and has had discussions with other
550 Id. at 3-6. 551 Id. 552 For more information on the 2009 Drought Water Bank, see the DWR website on the program [http://www.water.ca.gov/drought/bank/]. The Drought Water Bank has been challenged in litigation based on alleged violation of CEQA, in Butte Environmental Council et al. v. California Department of Water Resources et al., Alameda County Super. Ct. Case No. RG 09446708 (filed April 13, 2009). The petitioners in the action have not sought preliminary relief, and it is expected that the Drought Water Bank will have completed its operations on September 30, 2009, before the court action reaches trial, thus mooting the challenge. AUGUST 25, 2011 171
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potential sellers of water rights.553 Transfers of Table A entitlement are relatively easy to accomplish, because they do not require the regulatory approvals normally associated with water transfers, but must only be approved by DWR. For purchases of non-SWP water supplies, approvals must be obtained from the SWRCB and, in the case of CVP water, the USBR. Any water transfer lasting more than one year requires environmental review under CEQA.554
In addition to the possibility of increasing imported surface water supplies, CON could also seek new local water supplies. As mentioned in Sections 4.6.1 and 7.3.4.2 above, CON does not currently use local groundwater, but has shown interest in developing groundwater in the past.555 The City has specifically studied the use of groundwater on the Project site as a dry year supply, but would not be limited to the location of wells there.556 Since CON has a surplus of water supplies during 93 percent of all water years, and only needs to correct a deficit during the remaining 7 percent of single dry years, CON would not need to pump groundwater on a regular basis but would extract groundwater in single dry years when needed. In this way, CON would conjunctively use imported and local surface water and local groundwater supplies to meet its projected water demands. The City would not need to obtain any regulatory permits to extract local groundwater from within CON limits, and would require only a County permit within the jurisdiction of the County of Napa. The City would need to comply with the environmental review process of CEQA prior to initiating a groundwater development program.
The City in its 2005 UWMP concluded that it will have sufficient water supplies in future to meet the demands of customers in its water service area, despite the presence of a numerical deficit when comparing projected demands and firm supplies in single dry years. The City reached that conclusion based on the potential actions it could take to correct that deficit, as described above. Even though the quantity of that deficit is higher as analyzed in this WSA than in the CON UWMP, the same conclusion is reasonable here, for several reasons.
First, events since 2005 have increased the likelihood and quantity of carryover and Article 21 water available to CON from the SWP. While strict quantification is not possible, it is likely that CON would be entitled to at least 5,275 AFY of carryover water in a single dry year, plus Article 21 water that would likely be available. Second, DWR has demonstrated its ability to successfully coordinate dry year water supply programs through the implementation of the 2009 Drought Water Bank, through which CON has acquired an additional 1,780 AF. Third, CON has the ability to decrease its water demands as well as increase its supplies. In 1991, CON reduced its demands by more than 31 percent, and while that same figure may not be repeatable due to permanent water conservation measures undertaken since that time, it demonstrates that demand management can have a substantial impact on the supply-demand balance during a single dry year. Based on these and other actions described in this WSA, CON is projected to be able to supply water to all its water customers, including the Project, during single dry years over a 20- year horizon and beyond.
553 CON UWMP, at 3-6 [Exhibit B]. 554 See CAL. WATER CODE § 1729 (CEQA exemption for temporary transfers). 555 CON UWMP, at 3-7 [Exhibit B]. 556 WYA Technical Memorandum [Exhibit M]. 172 AUGUST 25, 2011
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7.5 Changes in the CON 2010 UWMP
The analyses in Sections 7.2 through 7.4 were originally prepared as part of the Water Supply Assessment for the Napa Pipe Project, Napa County, California, dated October 15, 2009. Since that time, CON prepared and adopted an Urban Water Management Plan 2010 Update, which updated the city’s water plans for events that have occurred between 2006 and 2011.557 Rather than replace the earlier analyses with a new analysis based on the CON 2010 UWMP and risk confusing public reviewers and decision-makers, this Section 7.5 discusses the changes from the CON UWMP to the CON 2010 UWMP. As described below, those changes do not substantially alter the conclusions of this WSA.
As shown in Table 35, CON has reduced its projected water demands based on lower population growth and increased water conservation measures. In 2009, the Association of Bay Area Governments revised its population projections for the region.558 For the CON water service area, population growth projections have been significantly scaled downward and skewed toward earlier years within the planning period.559
In December 2008, the CUWCC revised its MOU to reorganize the 14 BMPs and create two alternative compliance methods, Flex Track and GPCD (gallons per capita day). CON has chosen to comply with the MOU based on the GPCD method and is on track to meet future compliance targets.560 Additional water conservation requirements have been imposed on urban water purveyors by the Water Conservation Act of 2009 (SBx7-7), which seeks to achieve a 20 percent reduction in statewide urban per capita water usage by 2020, with an interim goal of 10 percent savings by 2015. CON has calculated its baseline per capita water use to be 164.9 gpcd using the 10-year period of 1995-2004. The city’s targets are 148.4 gpcd in 2015 and 131.9 gpcd in 2020. CON expects to meet those targets based primarily on reducing landscape irrigation demands through: maximizing the water efficiency of new developments; offering education and incentives for existing customers to increase their landscape water use efficiency; and supporting expanded use of NSD recycled water within the CON water service area.561
Table 35. Projected Population and Water Demands of the City of Napa 2010 2015 2020 2025 2030 2035 Service Area Population 86,743 89,243 90,743 91,743 92,643 93,543 Normal Year Water 13,442 14,895 14,303 14,260 14,391 14,522 Demands (AFY)
Source: CON 2010 UWMP, at Table 2-1, Table 5-6.
Regarding water supplies, CON intends to rely in future on the supplies identified in 2005, with three modifications. First, in 2009 the SWP contract between NCFCWD and DWR was amended to accelerate the entitlement schedule, with CON granted its full 2021 entitlement of
557 City of Napa, Urban Water Management Plan 2010 Update (June 21, 2011) [http://www.cityofnapa.org/- index.php?option=com_content&task=view&id=262&Itemid=353] (hereafter “CON 2010 UWMP”). 558 See Association of Bay Area Governments, Building Momentum: Projections and Priorities 2009 (2009). 559 CON 2010 UWMP, at 2-3, Table 2-1. 560 Id. at 5-3 through 5-8. 561 Id. at 5-8 through 5-14. AUGUST 25, 2011 173
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18,800 AFY beginning in 2010. This results in more water being available to CON between 2010 and 2020.562 Second, in early 2011 CON completed the expansion of its Jamieson Canyon WTP to a capacity of 20 MGD, which allows the city to increase its utilization of SWP supplies. This project was discussed in Section 7.3.3.3 and completed substantially as expected.563
Third, the reliability of the SWP has been revised so that average expected delivery amounts have decreased in comparison to previous estimates due to fishery protections, climate change assumptions and other unsettled legal and environmental factors.564 The CON UWMP in 2005 based its SWP reliability assessment on a 2002 report published by DWR. In contrast, Section 7.3.3.4 of this WSA was based on a 2007 update to that report, and the CON 2010 UWMP relies upon a 2009 update from DWR.565 For the 2009 update, DWR split its analysis into two scenarios: “Current Conditions” which includes the impact of the recent biological opinions for fish species discussed in Section 5.4; and “Future Conditions” which adds the effects of climate change. The CON 2010 UWMP used Current Conditions to estimate water supplies through 2025 and Future Conditions for years after 2025. The revised delivery estimates for those conditions are shown in Table 36.566 When compared to the reliability assessments in Table 30, it can be seen that the new CON 2010 UWMP assumptions generate lower SWP yield in normal years and roughly equal or higher SWP yield in multiple dry and single dry years.
As discussed in Section 7.4 of this WSA, CON is projected to have a surplus of water under normal and multiple dry years, both with and without the Project. That conclusion would remain under the analysis contained in the CON 2010 UWMP, based on reduced city water demands and water supplies that remain similar or higher under the updated assumptions. This can be seen by comparing the water supplies in Table 33 with the reliable water supplies in Tables 4-6 and 4-7 of the CON 2010 UWMP.567 In single dry years, the projected deficit conditions would continue to exist until 2025 but be lessened in magnitude under the new 2010 analysis, again because of reduced city water demands and water supplies that are similar or higher under the new assumptions. Beginning in 2030, it is expected that CON water supplies will be sufficient to meet all city demands in single dry years, which is a change from the CON UWMP in 2005.568 If the demands of the Project were added to the CON water service area, it would increase the amount of deficit through 2025 by 620 AFY, and change a slight surplus to a deficit beginning in 2030. In every scenario, the CON would have an improved ratio of water supply to demand under the updated analysis as compared to the analysis in Section 7.4.569
562 Id. at 3-4. 563 Id. at 3-5 through 3-7. 564 Id. at 4-1 through 4-7. 565 Id. at 4-2. See California Department of Water Resources, The State Water Project Delivery Reliability Report 2009 (August 2010); California Department of Water Resources, The State Water Project Delivery Reliability Report 2007 (August 2008); California Department of Water Resources, The State Water Project Delivery Reliability Report 2002 (2003). All three reports can be found online at http://baydeltaoffice.water.ca.gov/- swpreliability/. 566 CON 2010 UWMP, at 4-2. 567 Id. at 4-5. 568 See id. at 7-1. 569 See id. at 7-1 through 7-3 174 AUGUST 25, 2011
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Table 36. State Water Project Reliability Assessments (2009) Current Conditions Future Conditions (2010-2025) (2026 and Beyond)
Water Year Type Projected SWP Delivery Base Years Probability of Exceedence Projected SWP Delivery Base Years Probability of Exceedence
Normal Year 60% 1922-2003 65% 60% 1922-2003 61% Multiple Dry Year 34% 1929-1934 89% 32% 1987-1992 90% Single Dry Year 7% 1977 100% 11% 1977 100% Source: CON 2010 UWMP, at 4-2.
Regarding the Napa Pipe Project, the CON 2010 UWMP states that: “In the south of Napa, the Napa Pipe project proposes phased development of a high-density mixed-use residential neighborhood on the former Napa Pipe industrial property…. The Napa Pipe project EIR proposes use of recycled water generated on-site or by NSD. For potable water, Napa Pipe proposes both groundwater and surface water options. The surface water option would need to include water rights purchased from an entity outside of Napa County, but the water would have to be conveyed via the NBA and treated at either the City’s Edward I. Barwick Jamieson Canyon WTP or the City of American Canyon WTP. This would be a treat-and-wheel situation that does not use existing or projected City of Napa supply sources.”570 That statement is generally consistent with the discussion of water supplies in this WSA.
Based on this analysis, there is nothing in the CON 2010 UWMP to change the conclusion that CON would have sufficient water supplies to serve the Project. In fact, the efforts CON has made to reduce its urban water demands have improved and will continue to improve the city’s water supply outlook when compared to earlier analyses. If CON desired to be the water purveyor for the Project using its own supplies, it could reasonably provide water service to the Project.
7.6 City Water System Hydraulic Impacts and Infrastructural Analysis
In addition to the analysis presented above regarding the sufficiency of water supplies to meet the demands of CON’s water customers, including the Project, this WSA describes several improvements to CON’s water infrastructure that might be required to serve the Project. On August 21, 2008, WYA provided CON with an evaluation of its water system and potential service to the Project. The purpose of the resulting Technical Memorandum was to describe the Project, estimate water demands for the Project, and evaluate the Project’s hydraulic impacts on CON’s overall water system infrastructure. The Technical Memorandum also included a description and estimated construction cost of required improvements to CON water system to meet the projected water needs of the Project. These infrastructure needs are discussed below.
570 Id. at 5-18. AUGUST 25, 2011 175
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Since the preparation of the Technical Memorandum in 2008, the proposed Project has been modified from its earlier scope. Thus, although the Technical Memorandum estimated the potable water demands of the project to be up to 897 AFY, as analyzed in Section 3 of this WSA those demands are now projected to be 620 AFY. While the Technical Memorandum included a 10 percent contingency increase for potential changes to the project, in fact those changes have reduced the water demands associated with the Project by approximately 30 percent from the 897 AFY figure. Based on that change, the analysis conducted by WYA in the Technical Memorandum overestimates the water infrastructure needs of the Project, and the results of that analysis represent a very conservative, i.e., very high, projection of the impacts of the Project on City water infrastructure.
7.6.1 Storage Evaluation
WYA evaluated CON’s available treated water storage capacity based on CON’s 2006 demands. The storage evaluation was conducted by pressure zone to evaluate the overall storage available, as well as the location of the available storage in relation to the service area pressure zone. The WYA Technical Memorandum found that while there is adequate storage at or above Pressure Zones 1, 2 and 3 to meet the required storage criteria by gravity, there is inadequate storage within the higher pressure zones (Zones 4 and 5) to meet the required storage criteria by gravity.571 Thus, water must be pumped from Pressure Zone 3 to meet the storage requirements in the higher pressure zones. Redundant pumps and backup power have been integrated into the design and construction of Zone 3 pump stations to provide reliable service to the upper pressure zones, if required. The report found that overall, on a system-wide basis, the total treated water storage available (33.21 million gallons) is adequate to meet the total treated water storage required (28.7 million gallons) within the existing system based on current demands.572
WYA evaluated CON’s available treated water storage based on CON’s future demands (both 2020 and 2030). These future demands include demands for the Gasser Master Plan Project and maximum General Plan land uses on the Ghisletta/Horseman’s site, both located within CON’s existing service area. This future storage evaluation does not include the projected water demands of the Project. WYA found that in 2020 there would be a system-wide water storage shortfall of about 1.4 million gallons.573 In 2030, the system-wide shortfall will increase to about 3.0 million gallons. As part of its existing capital plans, CON is planning to construct an additional 2 million gallons of storage by 2020. This would meet the storage shortfall for 2020. However, an additional 1 million gallons of storage would then be required to meet the 2030 storage shortfall for growth inside CON’s water service area.574 Even though the existing storage analysis shows some surplus available storage capacity within CON’s system, CON has stated its intention to reserve this surplus storage to serve CON’s planned growth excluding the Project.
Furthermore, future storage analyses for 2020 and 2030 show future storage shortfalls within CON’s system. The WYA analysis found that there is no available storage capacity for the Project. The estimated total required storage for the project is 2.48 million gallons. Therefore,
571 WYA Technical Memorandum, at 18 [Exhibit M]. 572 Id. 573 Id. at 20. 574 Id. 176 AUGUST 25, 2011
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WYA concluded that additional future treated water storage facilities would be required for the Project.575 Depending on the location for increased required storage facilities, a corresponding pump station may also be required to ensure that the facilities can be properly integrated into CON’s system.
7.6.2 Analysis of Existing Water Distribution System
WYA analyzed CON’s water distribution system under May 2006 demand conditions, assuming the construction of the same future projects as noted above. Under this May 2006 demand scenario, only the Jamieson Canyon WTP was assumed to be operating. Peak hour flows from the Jamieson Canyon WTP are within the treatment capacity of the expanded Jamieson Canyon WTP of 20 MGD, but exceed the 15.8 MGD hydraulic system capacity of CON’s system. Flows above 15.8 MGD cause an unacceptable decrease in system pressures in certain locations. To mitigate the hydraulic impacts of flows from the Jamieson Canyon WTP above 15.8 MGD would require the construction of the proposed Westside Pump Station. If there were no Westside Pump Station, CON would need to operate the Hennessey WTP and/or provide additional supplies from storage to meet the peak hour demand condition.576
According to the WYA analysis, under existing maximum day demand conditions the introduction of the Project would have little hydraulic impact. Under existing peak hour demand conditions, the introduction of the Project would also have little hydraulic impact.577
Under the existing peak hour demand condition, WYA also evaluated the hydraulic condition assuming that the existing 16-inch pipeline construction along Highway 221, north of the Project was removed and upsized to a 24-inch pipeline, to determine whether this system modification could improve system pressures. Pressures in the area near the Project decrease by 2 to 3 pounds per square inch (“psi”) due to increased head loss in the 24-inch pipeline due to higher flows. Because the hydraulic grade line of the Jamieson Canyon WTP is higher than the hydraulic grade line of the Alston and Imola Tanks, the system pressures increase. WYA concluded that because the pressure increases are relatively small system-wide, there would be no need to increase the size of this pipeline.578
Under existing maximum day demand plus fire flow conditions, the Project also would have little hydraulic impact. Currently, water pressures in the CON distribution system range from 36 psi to about 114 psi. With the addition of the Project, pressures in CON’s system would range from a low of about 35 psi to a high of about 108 psi (in the Project area). Similar results occur under peak hour demand conditions. Thus, the Project would not cause any significant hydraulic impact on CON’s potable water distribution system.579
7.6.3 Analysis of Future Water Distribution System
WYA also analyzed CON’s system under future (2030) conditions, following the projections contained in the CON UWMP. The WYA Technical Memorandum assumed that the Jamieson
575 Id. at 21. 576 Id. at 23. 577 Id. 578 Id. at 26. 579 Id. at 23 AUGUST 25, 2011 177
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Canyon, Hennessey and Milliken WTPs were all operating. As shown in Table 37, flows from the Jamieson Canyon WTP are up to 20.3 and 21.5 MGD under maximum day demand conditions and 23.4 and 26.8 MGD under peak hour demand conditions, and flows from the Hennessey WTP are up to 17.2 MGD to serve future demand conditions. Flows from Milliken WTP were assumed to be zero for the purpose of the analysis. The required maximum day demand flows from the Jamieson Canyon WTP demonstrate the need for CON’s current expansion of the Jamieson Canyon WTP and the planned construction of the Westside Pump Station. WYA also noted that additional expansion to a treatment capacity of 24 MGD may be required in future at Jamieson Canyon WTP.580
Table 37. Summary of Flow from Each City Storage Tank to Meet Buildout Demand Conditions (2030) Flow Supplied (MGD) Buildout Buildout Buildout Peak Maximum Day + Maximum Day Hour Fire Flow
Source of Supply Storage Size (MG) Pressure Zone Served No NP NP No NP NP No NP NP Imola Tank 5 3 1.1 1.2 2.2 2.3 1.6 1.7 Alston Tanks 8 3 2.3 2.6 5.1 4.8 3.6 3.9 Lakeview Tank 5 1 4.4 4.4 8.1 8.1 4.4 4.4 B Tank 1 4 2.6 2.6 5.2 5.2 2.6 2.6 C Tank 2 2 4.8 4.8 8.2 8.2 4.8 4.8 Jamieson WTP 3 20.3 21.5 23.4 26.8 24.2 25.3 Hennessey WTP 3 0.0 0.0 17.2 17.1 0.0 0.0 Milliken WTP 3 0.0 0.0 0.0 0.0 0.0 0.0 Other City Storage 0.6 0.6 1.6 1.5 0.7 0.6 Total Supply 36.1 37.6 71.2 74.1 41.9 43.3 NP = Napa Pipe.
The peak hour flow requirements indicate that CON may need to operate the Hennessey WTP and/or provide additional supplies from storage (and possibly associated pump stations) to meet the peak hour demand conditions. Under future maximum day demand conditions, the Project has little hydraulic impact. Under future peak hour demand conditions, the Project also has little hydraulic impact.581 There is also little hydraulic impact under future maximum day demand plus fire flow conditions.
With the Project, the anticipated Westside Pump Station would need to be increased to a capacity of approximately 20.4 MGD to meet peak hour conditions. Therefore, the required incremental increase in the pumping capacity for the Westside Pump Station to mitigate for the Project is
580 Id. at 26. 581 Id. at 28. 178 AUGUST 25, 2011
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about 1 MGD.582 Based on WYA’s evaluation, an increased pipeline diameter in the area would not significantly improve hydraulic conditions.
7.6.4 Required New City Infrastructure to Serve the Project
The following summarizes what WYA determined to be the new water system infrastructure that would be required for CON to provide potable water service to the Project as originally proposed (with higher water demands, as described above):
• A new treated water storage facility with a total useable capacity of approximately 2.5 million gallons to provide for operational, fire flow and emergency storage for the Project and associated pump station which allows this tank to be integrated into CON’s system, depending on the location of the storage facility;
• Incremental pumping capacity increase of 1 MGD (from 19.4 to 20.4 MGD) for the proposed new Westside Pump Station in the southwestern portion of CON’s distribution system in order to provide for adequate system pressures during peak hour demand conditions at buildout; and
• Incremental treatment capacity increase of 1 MGD (from 20 to 21 MGD) at the Jamieson Canyon WTP.583
Estimates of probable construction costs for the required new infrastructure for CON to serve the Project are described below. These costs are for facility construction only and do not include costs for land acquisition. The costs include markups for contingencies, engineering and contract administration.
Construction costs for the new 2.5-million gallon treated water storage facility are estimated to be about $2.3 million, and are based on actual construction costs for CON’s recently constructed tanks. With markups as described above, the total cost of the new storage facility is estimated at $3.7 million.584 This cost does not include the costs of an associated pump station that might be needed depending on the location of the new storage tank.
Construction costs for the 1-MGD incremental increase in pumping capacity at the proposed new Westside Pump Station are based on expanding the proposed 19.4-MGD pump station to 20.4 MGD. This expansion is estimated to bear an additional cost of about $350,000. With markups, the total incremental cost is estimated to be about $560,000.585
Construction costs for the 1-MGD incremental increase in treatment capacity at Jamieson Canyon WTP are based on estimated construction costs for the currently pending expansion. The construction cost for that expansion is estimated to be $35 million ($41 million with construction management included). Expansion beyond the 20-MGD capacity to 24 MGD would require approximately two new filters and enhancements to the sedimentation basin. The
582 Id. 583 Id. at 30, 32. 584 Id. at 31. 585 Id. AUGUST 25, 2011 179
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estimated costs of these improvements are about $2.5 million.586 According to the WYA Technical Memorandum, the Project would be responsible for 25 percent of these expansion costs, approximately $625,000. In total, the costs of the proposed new facilities would be approximately $4,885,000.
As explained above, the WYA Technical Memorandum overestimates the impacts to CON water distribution system based on the lower water demands of the current Project when compared to the earlier scope of the project analyzed by WYA. Thus, the water infrastructure demands of the Project, and their associated capital costs, would be less than those described in the WYA Technical Memorandum. The figures discussed here serve as an upper ceiling for the water infrastructure improvements needed for CON to serve the Project and demonstrate that water service by CON is feasible, even with higher water demand numbers.
586 Id. 180 AUGUST 25, 2011
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SECTION 8 AVAILABILITY OF SUFFICIENT SUPPLIES
As described in the preceding sections of this WSA, potable water demands of the Project are projected to be approximately 620 AFY, and non-potable demands will be approximately 141 AFY. A comparison of water demands and proposed supplies for the Project are shown in Table 38.
Table 38 depicts total available surface water and groundwater supplies for the Project. Planned operations of the water system for the Project would entail the water purveyor importing as much surface water as possible, which is projected to vary from 456 to 620 AFY. Any additional water supplies would be obtained by the water purveyor producing as much groundwater as needed to serve the Project and leaving all remaining groundwater supplies in the aquifer underlying the Project site. As shown in the table, water supplies available to the Project will be far in excess of Project demands, leaving substantial surplus supplies of both local groundwater and imported surface water that may be used as a net benefit to other citizens of Napa County.
Table 38. Comparison of Water Supplies and Demands for the Project (2010-2030) 2010 2015 2020 2025 2030 Surface Water Supplies(a) 456 456 456 456 456 Groundwater Supplies 3,100 3,100 3,100 3,100 3,100 Project Demands (235) (620) (620) (620) (620) Other GW Demands(b) (1,037) (1,037) (1,037) (1,037) (1,037) Surplus (Deficit) 2,484 1,899 1,899 1,899 1,899 Non-Potable Water – NSD Alternative Recycled Water Supply(c) 3,590 3,590 9,800 9,800 9,800 Project Demands (51) (141) (141) (141) (141) Other User Demands(d) (1,184) (1,184) (7,019) (7,019) (7,019) Surplus (Deficit) 2,355 2,265 2,657 2,657 2,657 Non-Potable Water -- Onsite WWTP Alternative Recycled Water Supply 393 566 566 566 566 Project Demands (51) (141) (141) (141) (141) Surplus (Deficit) 342 425 425 425 425 All figures expressed in AFY. (a) Imported surface water figures are based on minimum water conveyance in the Maximum Year Scenario per Section 5.5.1. Water supplies on Mill Creek are much larger, with a minimum of 1,177 AF in the historical record and an average of 1,900 AF, after reducing for 12 percent conveyance losses. Thus, the limiting factor on imported water supplies for the Project is conveyance capacity, rather than water rights. (b) This table assumes that all existing and identified future water demands of other users begin in 2010. (c) This analysis assumes that NSD will implement its Strategic Plan starting in 2020; if that assumption is not fulfilled, recycled water supplies and demands from 2020-2030 will match those shown in 2015. (d) This represents the maximum water demands of all potential users of recycled water from NSD, which includes the Project starting in 2020.
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Based on all the analysis above and in the incorporated exhibits, this WSA concludes that the public water system to be constructed for the Project will have water supplies available during normal, single dry and multiple dry water years during a 20-year projection to meet the projected water demand associated with the proposed Project, and will not adversely affect the availability of water for any other use, including agricultural and manufacturing uses.
182 AUGUST 25, 2011