Draft Water Supply Plan
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Orange County, Virginia Orange County Water Supply Plan Report Draft Copy Wiley|Wilson Comm. No. 206060.00 July 6, 2007 Revised April 29, 2009 Orange County, Virginia Orange County Water Supply Plan Report Draft Copy Wiley|Wilson Comm. No. 206060.00 July 6, 2007 Revised April 29, 2009 Contact: Timothy R. Wagner, P.E. Project Manager 434.455.3681 .direct 434.947.1659 .fax [email protected] TABLE OF CONTENTS TAB Executive Summary.................................................................................................................... 1 Technical Memorandum Number 1 Figures .............................................................................................................................. 2 Tables ............................................................................................................................... 3 Table of Contents..............................................................................................................4 Report ............................................................................................................................... 5 Technical Memorandum Number 2 Table of Contents..............................................................................................................6 Report ............................................................................................................................... 7 Appendices Adequacy Analysis for Orange County Water Supply Study Calculations............................................................................................................A State Water Control Board Regulation 9 VAC 25-780 ..................................................................B Groundwater Exploration ............................................................................................................. C Alternative Analysis- Qualitative Assessment of Alternatives Using Analytical Hierarchy Process ........................................................................................... D McGuire Woods LLP Correspondence to Wiley|Wilson................................................................E Preliminary Construction Cost Estimate .......................................................................................F Virginia Water Protection Permit No. 02-1835 – Special Conditions (Town of Orange, VA) .................................................................................... G Orange Water Conservation Ordinance 02 - 08 Amended – 08-2006......................................................................................................... H VWP Individual Permit Reissuance No. 96-0271 Attachment A...................................................................................................................... I RSA East Drought Water Conservation Plan................................................................................ J Town of Gordonsville, Ordinance No. 23.19-02 through 12.19-05 ...............................................K Construction Schedule.................................................................................................................. L Recommended Water Audit.........................................................................................................M Orange County Water Supply Plan 206060.00 TOC-1 EXECUTIVE SUMMARY As a direct result of the drought of 1998 to 2002, the Commonwealth of Virginia adopted 9 VAC 25-780, "Local and Regional Water Supply Planning Regulations." These Regulations became effective November 2, 2005. The Regulations require that each jurisdiction in the State prepare and submit to the State a local water supply plan to be included in the State Water Supply Plan, upon approval. In addition, the State is currently in the process of revising the permit regulations for future water supply projects 9 VAC 25-210, "Virginia Water Protection Permit Programs." These two Regulations will be the first two steps in having a water supply project approved at the State level prior to obtaining a federal permit from the Corps of Engineers under the 401 and 404 combined permitting process. In order to comply with the water supply planning regulation and to begin the process of developing water supply solutions, Orange County initiated a regional water supply plan for the County; the Towns of Orange and Gordonsville; and the Rapidan Service Authority (RSA). To meet the regulation, the Orange County Water Supply Plan was assembled in two technical memorandums and affiliated appendices. Technical Memorandum No. 1 and Technical Memorandum No. 2, along with the Appendices to Technical Memorandum No. 2, serve as Orange County’s Water Supply Plan in accordance with 9 VAC 25-780, “Local and Regional Water Supply Planning Regulations.” Orange County was greatly impacted by the drought of 1998 to 2002. During this most recent drought, flows in the Rapidan River reached their lowest recorded flows since 1930. This was critical because approximately half of the County relies on public water supply. Ninety-nine percent of this public water supply is obtained from the Rapidan River. The Town of Orange and the Rapidan Service Authority (RSA) both have raw water intakes on the Rapidan River. The Town of Orange intake and water treatment plant provides public water to the Town of Orange, the Town of Gordonsville, and the US 15 Corridor between the two towns. The RSA Wilderness intake and water treatment plant provides public water to the citizens in the Wilderness area of Orange County. The only public water supply not utilizing the Rapidan River is the RSA Route 20 system groundwater system, which accounts for the remaining 1 percent of public supply. Groundwater from private wells provides the other half of the Orange County residents with water supply. Based on the highly variable nature of the fractured bedrock aquifers in the area, the accumulated existing well data shows a wide range of yields and well depths. Figure E-1 shows a population breakdown of where Orange County residents currently get their water. Orange County Water Supply Plan 206060.00 1-1 EXECUTIVE SUMMARY Figure E-1 Orange County Water Use in 2000 Town of Orange 16% Town of Gordonsville 6% Individual or Small Community Users 52% RSA Wilderness 24% Rapidan River RSA Route 15 RSA Route 20 Groundwater 1% 1% The drought of 1998 to 2002 peaked in the summer of 2002, resulting in record low stream flows and thousands of individual private well failures. During September of 2002, the Town of Orange was on the brink of a water shortage emergency and was developing emergency plans to pipe water from about 20 miles, near Culpeper, using a surface-laid pipeline. This was a dramatic reminder that water supply in Orange County is not unlimited, and that careful management is needed to ensure water availability for future generations. This is especially true considering the reoccurring nature of droughts in Virginia. The recent historical record shows that droughts occur approximately once every 20 to 30 years. The quantity of water in the Rapidan River and the quantity of groundwater in Orange County are relatively constant, but the number of people relying on these sources of supply will continue to grow. STATEMENT OF NEED As the population increases in Orange County, droughts will only exacerbate the competition for water resources. Population projections to the year 2050, with the percent increase for each of the water system’s service areas, are summarized in Figure E-2. Detailed population projections for each demand center are found in Technical Memorandum No. 2 Orange County Water Supply Plan 206060.00 1-2 EXECUTIVE SUMMARY Figure E-2 2050 Population Projection with Percent Increase 25,000 Town of Orange 342 % Town of Gordonsville 20,000 RSA Wilderness RSA Route 20 RSA Route 15 15,000 282 % Population 10,000 407 % 5,000 244 % 0 156 % 2000 2050 Year Based upon the current contractual agreements between the Towns and the RSA, some of the public water systems in Orange County could experience periods of water shortage as early as 2010. Although the duration and frequency of these water shortages cannot be accurately predicted, they will most likely first occur during the late summer and early fall, when stream flows and groundwater levels are typically at their lowest. All residents could be impacted, even though roughly half of the residents depend on the Rapidan River as a supply and the other half depend on groundwater. Dry wells could force some residents to purchase and transport containers of water for basic domestic use, while residents on public water systems in the County could likely face mandatory restrictions that will limit water use. The potential for water shortages in Orange County is caused by the following two primary conditions: • Increased Growth All of the large water demand centers in Orange County that have established public utilities will experience, on average, a 300 percent population growth from 2000 to 2050. This population surge will lead to a proportional increase in water demand. Orange County Water Supply Plan 206060.00 1-3 EXECUTIVE SUMMARY • No Growth in Water Supply There are no planned increases in available water supply rates for Orange County. Based on the present water supply and the projected maximum day demands in 2050, Figure E- 3 shows the amount of water deficits for all of the developed water systems. For example, the Figure shows that the Town of Orange has an overall demand in 2050 of 2.9 MGD with a supply of 0.9