Executive Summary. ES-1 Water Resources Infrastructure for Apex, Cary, Morrisville, and RTP South

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1 Executive Summary Since the mid-1990s the Towns of Apex, Cary, and Morrisville, and Wake County have worked to develop and manage a flexible portfolio of water resources options. This approach is preferable in resource planning to adapt to future conditions that may differ from current conditions. The Towns of Cary and Apex have a long history of developing plans to effectively manage their water resources and to ensure safe and reliable water supply for the communities they serve. Since 2000, the Towns have taken actions on the recommendations provided in the Long Range Water Supply Plan (CH2M HILL, 2000) and the Integrated Water Resources Management Plan (CH2M HILL, 2007). In the spirit of continuing to value the importance of long range water resources planning, starting in 2010 the Towns of Apex, Cary, and Morrisville, and Wake County worked through a structured two-phase process to develop this Long Range Water Resources Plan (LRWRP) and Water Resources Portfolio. This LRWRP takes a strategic long view through 2060 to prepare the Towns and County to meet their water resources challenges in a dynamic and holistic way, through development of a Water Resources Portfolio. The Portfolio provides a mix of practical strategies that can be applied by the Towns to meet their water resources responsibilities by implementing the right actions at the right time. ES-1 Water Resources Infrastructure for Apex, Cary, Morrisville, and RTP South The Towns of Cary and Apex jointly own a 40 million-gallon per-day (mgd) water treatment plant (WTP) with the source of water supply from Jordan Lake. Plans are underway to expand the plant capacity to 56 mgd. The Town of Cary provides potable water to customers in the Towns of Cary and Morrisville, the Wake County portion of the Research Triangle Park (RTP South), and the Raleigh-Durham (RDU) FIGURE ES-1 Towns of Apex, Cary, and Morrisville, and RTP South Urban Service Area Overview ES-1

2 International Airport. The Town of Apex provides water to customers in the Town and its planning jurisdiction. Each jurisdiction s urban service area, or planned utility service area, is shown in Figure ES-1. In addition to planning for each Town s service area, the Towns are part of the Jordan Lake Partnership (JLP) which is a regional partnership of 13 local governments proactively planning for the region s water resources needs. The Towns of Apex, Cary and Morrisville and Wake County hold Jordan Lake water supply storage allocations granted by the State of North Carolina with a nominal total yield of 39 mgd. Currently, most of this water is consumed and/or discharged as highly treated wastewater effluent in the Neuse River basin. As a result, an interbasin transfer (IBT) certificate, approved by the State s Environmental Management Commission (EMC), is required and was issued jointly to Apex, Cary, Morrisville and Wake County in Although the Towns are in the process of constructing a new regional water reclamation facility (WRF) that will discharge to the Cape Fear River downstream of Jordan Lake, any additional water supply allocation from Jordan Lake to the Towns could require a modification of the current IBT certificate. In addition to the Cary/Apex WTP, the Towns currently own and operate three WRFs and a fourth, which will help to satisfy the Towns current IBT certificate, is currently under construction. The WRF capacities are as follows: Town of Cary: o North Cary WRF 12 mgd o South Cary WRF 12.8 mgd Town of Apex o Middle Creek WWTP 3.6 mgd Towns of Apex and Cary (joint ownership) o New 18-mgd Western Wake Regional WRF (currently under construction) The Towns both hold permits to distribute reclaimed water from their WRFs for non-potable uses within their service areas. ES-2 Identifying the Needs for the Future Long range resource planning is dependent on conditions that may change in unpredictable ways. The farther in the future demands are projected, the greater the uncertainty in the forecast. Forecasting is critical for the Towns to plan, design, and construct capital-intensive infrastructure, which can take upwards of a decade before major water supply and treatment facilities can be placed online. The Towns are also subject to regulatory processes that can span an additional 3 to 10 years, including IBT certification and the Jordan Lake allocation process. Forecasting is essential to understanding the sensitivity of current supply capacity limitations and the timing for new supplies and infrastructure, ensuring that capacity is available to meet the needs of the community. The baseline water demand and wastewater flow forecasts developed for this LRWRP are representative of each Town s current programs and policies, including current conservation programs, and assume they continue into the future absent of any influence of major technology or regulatory changes. A probabilistic forecasting methodology was used to incorporate uncertainty into the baseline water demand forecast, providing the ability to understand the variability in the potential future demands. ES-2

3 Figure ES-2 displays the baseline annual average day raw water demand forecasts for the combined service areas of the Towns of Apex and Cary. Figure ES-3 shows the baseline maximum day finished water demand forecast. Figures ES-2 and ES-3 present the 5 th, 25 th, 50 th, 75 th, and 95 th percentile forecasts. These probabilistic forecasts represent an estimate of the probability of occurrence of the identified level of demand and below (e.g., there is a 95 percent chance that the water demand in a particular year will be equal to or less than the 95 th percentile forecasted demand for that year). The factors that were integrated as probabilistic variables in the probabilistic baseline water demand forecast model are: Growth rate (rate at which new development occurs) Annual variability in water use due to weather (change in average annual use) Amount of process water used during the treatment process Non-revenue water (percentage of total finished water demand) Maximum day peaking factors (maximum day versus annual average daily) FIGURE ES-2 Annual Average Daily Raw Water Demand, Towns of Apex, Cary, and Morrisville, RDU Airport, and RTP South, 2002 through Raw Water Annual Average Daily Demand (mgd) Historic Raw Water Demand Baseline Raw Water Demand Projection (Median) Jordan Lake Allocation (39 mgd) 95th Percentile 75th Percentile 50th Percentile 25th Percentile 5th Percentile These forecasts identify the uncertainty in future water demand for the Towns of Apex, Cary, and Morrisville and RTP South, which is extremely relevant to understanding the potential risks in water supply capacity development decisions. For example, after planning, design, and construction of a highly capital-intensive supply alternative is initiated, if demand grows slower than projected, significant rate increases for current customers may be needed to pay the debt service. Alternatively, if demand growth occurs faster than projected, water supply shortages ES-3

4 could have an unintended economic impact on the Towns, limiting growth. Although both scenarios are extreme, they represent the worst case on either end of the decision related to timing the development of new water supply and/or treatment capacity. FIGURE ES-3 Maximum Day Finished Water Demand Forecast, Towns of Apex, Cary, and Morrisville, RDU Airport, and RTP South, 2002 through 2060 Maximum Day Demand (mgd) Historic Finished Water Demand 95th Percentile 80 Baseline Finished Water Demand Projection (Median) 75 Cary/Apex WTP Capacity 75th Percentile 70 50th Percentile th Percentile th Percentile From the forecasts presented in Figures ES-2 and ES-3, it is apparent that the Towns will require additional water supply and treatment capacity. This additional capacity will likely need to be online by Based on the baseline 50 th percentile forecast: The 50 th percentile total raw water supply deficit in 2040 is approximately 5.0 mgd and in 2060 it is 8.5 mgd. The corresponding total additional water treatment capacity required by the Towns (beyond 56 mgd) will be 6.8 mgd in 2040 and 11.8 mgd in In addition to the baseline water demand forecast a baseline wastewater flow projection of an average day on a maximum month was also developed. Understanding the relationship between source basin water supply and eventual discharge to a receiving basin following use and treatment is critical to understanding IBT. Based on the wastewater flow projection, there is sufficient total wastewater treatment capacity for the Towns through 2060, assuming similar wastewater strengths to design levels. The following items outline the future long-term wastewater capacity considerations for the Towns: North Cary WRF capacity begins to be exceeded by 2030 and by 2060 there is a capacity deficit of 2.5 mgd. South Cary WRF is projected to have 2.8 mgd of excess capacity in ES-4

5 Western Wake Regional WRF capacity: o Cary is projected to have 2.6 mgd of excess capacity in the Town s 11.7 mgd capacity allocation of the Western Wake Regional WRF in o The Apex allocation of the Western Wake Regional WRF capacity, 6.3 mgd, is exceeded by o Overall Western Wake Regional WRF has 1 mgd of excess capacity available in 2060, if Apex is able to direct its projected wastewater flow to Western Wake Regional WRF. Middle Creek WRF is projected to have 1.2 mgd of excess capacity in Considered as a whole, the total required wastewater treatment capacity in 2060 is 44.5 mgd and the theoretically available capacity is 46.4 mgd, leaving 1.9 mgd of excess capacity (96 percent capacity utilization). Given the North Carolina Department of Environment and Natural Resources (NCDENR) requirement for facility expansion at 90 percent of capacity, it may be necessary to expand capacity at one or more facilities. In addition to the water demand and wastewater flow forecasts, future IBT was forecasted. Figure ES-4 presents the baseline IBT forecast for transfers from the Haw River basin to the Neuse River basin. FIGURE ES-4 IBT Forecast to the Neuse River Basin Compared to Current IBT Certificate Transfer Limit, , Maximum Day Historic IBT Baseline IBT Projection (Median) IBT Certificate Maximum Day Transfer Limit (24 mgd) Interbasin Transfer (mgd) 95th Percentile 75th Percentile 50th Percentile 25th Percentile 5th Percentile The IBT forecast indicates that the baseline 50 th percentile IBT (maximum day) for the Towns of Apex, Cary, and Morrisville, and RTP South could exceed the Towns current IBT certificate maximum day limit of 24 mgd in 2018; the baseline 75 th percentile IBT forecast would exceed this limit in This information indicates that the Towns will require a modification of their current IBT certificate to be able to fully access their current Jordan Lake water supply allocations. By 2060, the 24 mgd IBT certificate limit could be exceeded by approximately 12 ES-5

6 mgd. The baseline IBT forecast for transfers from the Haw River basin to the Cape Fear River basin, which are solely attributed to the Town of Apex, has a similar range of uncertainty as identified in Figure ES-4 with the 2060 IBT ranging from 2.3 to 3.8 mgd for the 25 th and 75 th percentile forecasts, respectively. ES-3 The Planning Process The LRWRP planning process is shown in Figure ES- 5, from identification of the initial strategies through the decision framework, screening and prioritization of strategies, and development of the Water Resources Portfolio. Phase I of the LRWRP included: Developing the project purpose and establishing the community values to guide the project Developing a long list of potential water resources strategies that support the purpose and values Establishing a decision framework and process by which to evaluate the strategies Applying the decision framework to narrow the strategies to a short list identified as the most applicable by local, national, and international water resources experts Phase II of the LRWRP included: Conducting scenario planning to define a shared vision of the future and developing pathways to meet the challenges of possible futures Prioritizing the short list of strategies Validating the most viable strategies as those best suited to position the Towns and County to achieve their future vision Identifying the most viable strategies to be included in the Water Resources Portfolio FIGURE ES-5 LRWRP Planning Process Overview Project Purpose Statement The Long Range Water Resources Plan will guide the development of reliable, flexible water supply and management solutions that are financially responsible, maintain the quality of service provided to the customers of Apex, Cary, Morrisville, and RTP South, and support our commitment to protecting public health and being good stewards of the natural environment. ES-6

7 ES-4 Water Resources Portfolio The Towns and County s vision for the future, as defined through scenario planning, framed the selection of a number of water resources strategies that support the project purpose. These strategies will increase the resiliency of the Towns, as well as the region, in responding to changing conditions into the future. These strategies comprise the Water Resources Portfolio and provide the Towns with the flexibility to: Continue to effectively manage water supply. Ensure that water resources are used most efficiently. Implement strategies over time as they become needed; and maintain the viability of a water supply strategy until it is no longer needed. Enable adaptation to changes in the future that are relatively uncertain, such as: o Economic and business trends and their impact on growth and land use patterns o Environmental regulations and requirements o Regional partnerships o Shifting societal trends The Water Resources Portfolio contains infrastructure solutions as well as adaptive management solutions. These strategies were selected through a value-based portfolio development process. The portfolio includes flexible timeframes for implementation of each strategy which do not preclude the implementation of other strategies concurrently or in the future. The following sections briefly describe the objective of each strategy within the portfolio. Tables ES-1 and ES-2 contain a summary of each strategy, including potential water supply capacity, implementation requirements, regulatory considerations, policy implications, key uncertainties, and other considerations. In addition, Table ES-1 presents the planning level capital cost estimates (in 2012 dollars), the net present value (NPV) for capital and operating costs through 2060, and the impacts to Cary residential customer monthly water bills for each water supply and interconnection strategy. Water Supply and Interconnections Strategy 1 Increase Water Supply via Jordan Lake Allocation The objective of Strategy 1 is to increase the average day raw water supply to the Cary/Apex WTP by obtaining additional allocation from the existing water supply pool of Jordan Lake, located in the Haw River basin. Strategy 2 Increase Water Supply and/or Storage by Other Means Water Resources Portfolio The Water Resources Portfolio consists of a range of strategies that will individually or collectively satisfy the project purpose. The portfolio itself represents a diverse set of strategies for implementation to provide the Towns with a robust set of options to meet and manage water supply needs into the future under a variety of uncertainties. Strategy 2 includes four potential options to increase water supply and/or water storage. The implementation of one or more of these options does not preclude the implementation of other options concurrently or in the future. ES-7

8 Strategy 2A Increase Jordan Lake Water Supply Pool The objective of Strategy 2A is to increase the average day raw water supply to the Cary/Apex WTP from the existing flood control or sediment storage pool of Jordan Lake. It is anticipated that water would be reallocated from sediment or flood control storage to the conservation pool, which would increase water supply storage. Strategy 2B Water Supply from Crabtree Creek with Storage in Existing Triangle Quarry The objective of Strategy 2B is to increase the water supply for the Towns and County by skimming high flows from Crabtree Creek and storing the water in the existing Wake Stone Corporation Triangle Quarry, located north of US I-40 and adjacent to Umstead Park. Strategy 2C Water Supply from Cape Fear River The objective of Strategy 2C is to increase the water supply for the Towns and County from a new water supply intake on the Cape Fear River downstream of Jordan Lake Dam and treated at either a new WTP or at the existing Cary/Apex WTP. Strategy 2D Water Supply from Kerr Lake The objective of Strategy 2D is to increase the water supply for the Towns and County from a new water supply intake on John H. Kerr Reservoir ( Kerr Lake ) and treat the water at a new or existing WTP. It is anticipated that this strategy would be executed in a joint venture with other Triangle region water providers. Strategy 3 Increase Water Supply and/or Storage via Interconnections The objective of Strategy 3 is to increase average day finished water supply through long-term water purchase agreements with other regional utilities, and then access the purchased water through existing or new interconnections. Management Tools and Resource Recovery Strategy 4 Integrated Master Planning and Strategic Utility Resource Utilization The objective of Strategy 4 is to integrate community planning, water resources management, utility planning, and sustainable development. Unifying these planning efforts will promote development practices that support the Towns and County s commitment to responsible growth and the wise use of water. Strategy 5 Best Management Practices Strategy 5 includes a number of water resources strategies described as best practices or management tools identified through the LRWRP process. These best practices include internal operations improvements, measures to enhance customer water use efficiency, and the utilization of reclaimed water. Individually or collectively, these practices and tools provide a robust set of options when used along with other strategies to prepare the Towns and County for a range of future conditions. They provide the Towns and County with a range of strategies: To increase flexibility in the management of available water supplies in the most conscientious manner. To increase the water resources resilience of each jurisdiction, which also improves overall regional resiliency. ES-8

9 That will enable the towns to adapt to a future affected by uncertainties related to the economic/business climate, technological advances, hydrologic /climate variability, and environmental regulatory changes. The Towns currently have programs in place that support the above attributes; this strategy continues and expands on a number of these programs. Strategy 5A Supply Side Management Optimize Internal Operations The objective of Strategy 5A is to optimize operations at the Cary/Apex WTP and the efficiency of the water distribution system operations and storage. These practices are under the complete control of the Towns of Cary and Apex. Strategy 5B Demand Side Management Manage Customer Demands for Improved Efficiency The objective of Strategy 5B is to influence customers to use water wisely - resulting in reduced water demand through policies. Demand side management approaches are increasingly relied upon for water resource management and complement more traditional supply side management measures. A combination of price-based and alternative (non-price-based) demand side management policies could be most beneficial. Strategy 5C Reclaimed Water The objective of Strategy 5C is to offset potable water system demands through the beneficial utilization of reclaimed water. This potential is explored in the Town of Cary s Strategic Reclaimed Water System Plan (CH2M HILL, 2012a) and is linked with Strategy 4. ES-9

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