Biological Technical Report for the Nob Hill Pipeline Improvements Project Prepared for Prepared by San Diego County Water Authority RECON Environmental, Inc. 4677 Overland Avenue 1927 Fifth Avenue San Diego, CA 92123 San Diego, CA 92101-2358 Contact: Mark Tegio P 619.308.9333 F 619.308.9334 RECON Number 6830 February 12, 2014; Revised June 2014 Brian Parker, Biologist THIS PAGE IS INTENTIONALLY BLANK. Biological Technical Report for the Nob Hill Pipeline Improvements Project TABLE OF CONTENTS Glossary of Terms and Acronyms iii Executive Summary 1 1.0 Introduction 5 2.0 Project Location, Description, and Environmental Setting 5 2.1 Project Location 5 2.2 Project Description 5 2.3 Environmental Setting 12 3.0 Methods 13 3.1 General Biological Survey 14 3.2 Jurisdictional Wetlands and Waters Delineation 15 4.0 Existing Conditions 16 4.1 Physical Setting 16 4.2 Vegetation Communities/Land Cover Types 17 4.3 Plant Species Observed Within the Study Area 24 4.4 Wildlife Observed Within the Study Area 24 4.5 Jurisdictional Wetlands and Waters 24 4.6 Habitat Linkages and Wildlife Corridors 28 5.0 Regional and Regulatory Context 28 5.1 Federal Endangered Species Act 29 5.2 Migratory Bird Treaty Act 29 5.3 California Endangered Species Act 29 5.4 California Fish and Game Code 29 5.5 Water Authority NCCP/HCP 30 5.6 City of San Diego Multiple Species Conservation Program 32 6.0 Sensitive Resources 32 6.1 Sensitive Vegetation Communities/Land Cover Types 33 6.2 Sensitive Plant Species 33 6.3 Sensitive Wildlife Species 35 7.0 Project Impacts 37 7.1 Direct Impacts 37 7.2 Indirect Impacts 49 8.0 Mitigation Measures 55 8.1 Vegetation Communities 55 8.2 Sensitive Species 57 i Biological Technical Report for the Nob Hill Pipeline Improvements Project TABLE OF CONTENTS (cont.) 9.0 Conformance with NCCP/HCP 57 10.0 References Cited 60 FIGURES 1: Regional Location 6 2: Project Location on USGS Map 7 3: Project Boundary 8 4 Existing Biological Resources 19 5: Jurisdictional Wetlands and Waters 25 6a: Alternative 1, Tunneling - Impacts to Biological Resources 39 6b: Alternative 1, Tunneling - Impacts to Biological Resources 41 7: Project Footprint in Relation to Jurisdictional Wetland and Waters 51 TABLES 1: Survey Information 14 2: Vegetation Communities/Land Cover Types within the Study Area 17 3: Existing Jurisdictional Wetlands and Waters within the Study Area 27 4: Impacts to Vegetation Communities/Land Cover Types: Alternative 1 – Tunneling 38 5: Overall Project Impacts to Vegetation Communities/Land Cover Types: Alternative 1 – Tunneling 43 6: Impacts to Vegetation Communities/Land Cover Types: Alternative 2 – Open Trench 43 7: Overall Project Impacts to Vegetation Communities/Land Cover Types: Alternative 2 – Open Trench 44 8: Impacts to Coastal California Gnatcatcher Occupied Habitat: Alternative 1 – Tunneling 47 9: Impacts to Coastal California Gnatcatcher Occupied Habitat: Alternative 1 – Open Trench 48 10: Mitigation for Impacts to Sensitive Vegetation Communities: Alternative 1 – Tunneling and Access Road 56 11: Mitigation for Impacts to Vegetation Communities: Alternative 2 – Open Trench and Access Road 56 ATTACHMENTS 1: Plant Species Observed Within the Nob Hill Pipeline Improvements Project Study Area 2: Wildlife Species Observed/Detected Within the Nob Hill Pipeline Improvements Project Study Area 3: Sensitive Plant Species Observed or with Potential to Occur within the Nob Hill Pipeline Improvements Project Study Area 4: Sensitive Wildlife Species Observed or with Potential to Occur within the Nob Hill Pipeline Improvements Project Study Area 5: NCCP/HCP Standard Minimization Measures for Construction Activities ii Biological Technical Report for the Nob Hill Pipeline Improvements Project Glossary of Terms and Acronyms BMP Best Management Practice BSRA Biologically Significant Resource Area CDFW California Department of Fish and Wildlife CEQA California Environmental Quality Act CFR Code of Federal Regulations City City of San Diego CNDDB California Natural Diversity Data Base CNPS California Native Plant Society CRPR California Rare Plant Rank CWA Clean Water Act ESA Endangered Species Act HMA Habitat Management Area MBTA Migratory Bird Treaty Act MCAS Marine Corps Air Station MHPA Multi-Habitat Planning Area MSCP Multiple Species Conservation Program MSL Mean Sea Level NCCP/HCP Natural Community Conservation Plan/Habitat Conservation Plan NPDES National Pollutant Discharge Elimination System O&M Operations and Maintenance PIZ Probable Impact Zone PSF Pre-activity Survey Form ROW Right-of-Way RWQCB Regional Water Quality Control Board SWRCB State Water Resources Control Board USDA U.S. Department of Agriculture USACE U.S. Army Corps of Engineers USFWS U.S. Fish and Wildlife Service USGS U.S. Geological Survey Water Authority San Diego County Water Authority iii Biological Technical Report for the Nob Hill Pipeline Improvements Project THIS PAGE IS INTENTIONALLY BLANK. iv Biological Technical Report for the Nob Hill Pipeline Improvements Project Executive Summary The San Diego County Water Authority’s (Water Authority’s) proposed Nob Hill Pipeline Improvements Project (project) would replace and realign approximately 800 feet of the Second Aqueduct Pipelines 3 and 4, and develop an access road for construction and maintenance. This report assesses three project components: pipeline improvements, access road, and staging area. Two pipeline improvement alternatives are being considered: Tunneling (Alternative 1) and Open Trench (Alternative 2). Construction staging would likely occur off-site on a previously graded pad south of Scripps Lake Drive. Additionally, the Water Authority would construct a permanent paved access road that would extend from Scripps Lake Drive to a private road in the Scripps Nob Hill community. The proposed project is located in the community of Scripps Ranch, in the northeast portion of the City of San Diego (City), California. The project site is primarily within the Water Authority right-of-way (ROW) but includes portions outside the ROW, for which temporary easements from the City would be acquired. This report describes the existing biological resources in accordance with the requirements of the Water Authority Natural Communities Conservation Plan/Habitat Conservation Plan (NCCP/HCP; Water Authority 2010), discusses project impacts to biological resources, and provides corresponding mitigation recommendations for the project. The biological study area for this project includes an approximately 200-foot buffer around the proposed project alignment, which encompasses the two alternatives, access road, and staging area. Biological studies conducted for this project include a general biological survey, including vegetation mapping and plant and wildlife inventories and a delineation of jurisdictional wetlands and waters. Eleven vegetation communities and land cover types occur within the study area: southern willow scrub, freshwater marsh, open freshwater, Diegan coastal sage scrub (including disturbed), coastal sage-chaparral scrub, revegetated habitat, southern mixed chaparral (granitic, including disturbed), eucalyptus/non-native vegetation, disturbed habitat, ornamental vegetation, and urban/developed land. Seven of these are considered sensitive vegetation communities by the Water Authority (Water Authority 2010): freshwater marsh, southern willow scrub, open freshwater, Diegan coastal sage scrub (including disturbed), coastal sage-chaparral scrub, southern mixed chaparral (including disturbed), and revegetated habitat. Revegetated habitat represents areas that were impacted by the Water Authority’s Pipeline 3 and 4 Relining Project and are in the process of being restored. As such, any impacts to these areas will require mitigation. The majority of the revegetated habitat supported Diegan coastal sage scrub prior to that project, while the remainder, which is not impacted by this project, primarily supported chaparral. Page 1 Biological Technical Report for the Nob Hill Pipeline Improvements Project The study area supports wetlands and/or waters jurisdictional to the U.S. Army Corps of Engineers (USACE), California Department of Fish and Wildlife (CDFW), and Regional Water Quality Control Board (RWQCB). The project has been designed so these jurisdictional wetlands and waters lie outside the project footprint and would not be impacted. Three sensitive plant species occur, or have moderate to high potential to occur, within the study area: ashy spike-moss (Selaginella cinerascens), San Diego County viguiera (Bahiopsis laciniata), and western dichondra (Dichondra occidentalis). None of these species is federally or state listed, and none is considered a covered species per the NCCP/HCP. Ashy spike-moss is identified by the California Native Plant Society (CNPS) as a California Rare Plant Rank (CRPR) 4.1 species, and San Diego County viguiera and western dichondra are identified as CRPR 4.2 species. Three sensitive animal species occur or have moderate to high potential to occur in the study area: Belding’s orange-throated whiptail (Aspidoscelis hyperythra beldingi), coastal California gnatcatcher (Polioptila californica californica), and Southern California rufous- crowned sparrow (Aimophila ruficeps canescens). Belding’s orange throated whiptail is not federally listed but is a CDFW species of special concern. The coastal California gnatcatcher is federally listed as threatened and is a CDFW species of special concern. The southern California rufous-crowned sparrow is not federal or state listed.