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SOURCE - Winter 2016 13 At build-out, the project will produce 168,000 acre-feet a year (AFY) of advanced treated water. Current plans are to proceed in phases, at the rate of approximately 67,000 AFY. Metropolitan estimates the project will require construction of approximately 30 miles of distribution lines, for which planning is currently in very preliminary stages. Locally, only the Groundwater Replenishment System (GWRS), developed through a partnership between the Orange County Water and Sanitation districts, operates on this scale. The GWRS currently produces 103,000 AFY of advanced treated water, which makes it the world’s largest water purification project for indirect potable reuse. According to Metropolitan Program Manager John Bednarski, the pilot plant will have “the look and feel” of the City of San Diego’s Pure Water advanced treatment demonstration plant, which has been operating since 2009. “Generally we’re looking at a membrane bioreactor with micro- or ultrafiltration, reverse osmosis, UV and then some kind of post-treatment prior to putting it in the ground.” San Diego’s one-MGD pilot plant was developed to demonstrate that a treatment train based on the one in use at the GWRS, would meet all state and federal drinking water standards and be suitable for surface augmentation in the city’s San Vicente Reservoir. San Diego’s plans call for a 30 MGD water purification facility to be operational by 2021, with a long-term goal of 83 MGD by 2035, one-third of the city’s future drinking water supply. With an average delivery of 1.7 billion gallons of water per day, Metropolitan is the largest distributor of treated drinking water in the United States. In addition to the Colorado River Aqueduct, it owns and operates nine reservoirs, 819 miles of large-scale pipes and five water treatment plants, four of which are among the 10 largest in the world. Given current and projected future conditions, however, the 26-member agency is planning for supply diversification. According to Bob Harding, Metropolitan Resource and System Analysis Unit Manager, the focus is on “improving sustainable yield and developing a diverse resource mix” to ensure a stable water supply for the 19 million people the district serves in Los Angeles, Orange, Riverside, San Bernardino, San Diego, and Ventura counties. A November 10, 2015 staff letter to the Metropolitan Board of Directors cites the unprecedented drought over the past eight years, which has resulted in reductions in local surface supplies and groundwater production, along with climate uncertainties and hydrologic variability in imported supplies as rationale for the development of local sources. The staff also notes that projected groundwater production within Metropolitan’s service area has fallen by approximately 250,000 AFY, and 150,000 AFY called for in its 2010 Integrated Resources Plan to meet water use efficiency and local supply targets has not been produced by projects that have come online or begun construction in the past five years. Our mission is to convert what others consider a waste into a resource. Our priority has always been our upstream plants, which generate tertiary treated water, but we started to look at 250 million MGD we’re putting in the ocean at The 24-member Sanitation Districts convey and treat approximately half the wastewater in Los Angeles County through 11 treatment plants, of which the JWPCP is the largest. “Our mission is to convert what others consider a waste into a resource,” says Robert Ferrante, Sanitation Districts Assistant Chief Engineer. “Our priority has always been our upstream plants, which generate tertiary treated water, but we started to look at 250 million MGD we’re putting in the ocean at the joint plant. The size of the plant was a challenge, which is why it makes sense for us to partner with a regional agency.” Not all of Metropolitan’s member agencies are onboard with the planned recycled water delivery program. While affirming its commitment to development of recycled water and local supplies, the San Diego County Water Authority (Water Authority) has gone on record opposing Metropolitan’s agreement with the Sanitation Districts and the $15 million pilot plant appropriation. The Water Authority is San Diego County’s water wholesaler, providing water to 24 member agencies. In a November 9, 2015 letter to Board of Directors, the Water Authority charges that Metropolitan has “failed to conduct a cost of service study” to support its allocation of costs associated with the regional groundwater program and the demonstration project. The letter expresses the Water Authority’s concern that its customers are not likely to “directly or indirectly benefit” in relation to project costs and puts the Metropolitan Board on notice that it will seek to recover “any and all rates and charges” imposed in connection with the recycled water delivery program. (See Speaking Out on page 24 in this issue for SDCWA’s plans to reduce the San Diego region’s dependence on imported water, and SOURCE, Spring 2015, for Los Angeles Department of Water and Power’s San Fernando Basin replenishment project, which will use 30,000 AFY of purified effluent from the Sanitation Districts’ Donald C. Tillman Water Reclamation Plant for groundwater recharge.) Robb Whitaker is General Manager of the Water Replenishment District of Southern California (WRD), which manages groundwater for four million people in 43 cities, accounting for 40 percent of the region’s water supply. WRD’s 420-square mile service area uses about 250,000 AFY of groundwater, pumped from aquifers in the Central Coast and West Coast Basins. Despite the current drought and low groundwater levels, Whitaker says WRD doesn’t need Metropolitan’s purified water for aquifer recharge. The water could be “perfect,” however, for almost 500,000 acre-feet of groundwater storage that is currently going unused. “For a dozen or so years we’ve gone back-and-forth about that space. The debate finally culminated in amending the existing adjudications and allowing it to be utilized. To the degree that we use storage so that groundwater makes up a large proportion of the water supply,” says Whitaker, “we can drought-proof the region.” Metropolitan’s Regional Recycled Water Supply Program pilot water purification facility will be financed as a 2015-16 capital project under its Capital Investment Plan. The Board of Directors is scheduled to authorize agreements for design of the demonstration plant in February 2016; review the financing plan for the full-scale project, delivery system feasibility studies, and demonstration plant data in October/November 2016; and award the construction contract and potentially certify environmental documentation for a full-scale program in December 2016. S “ ‘‘ the joint plant. ROBERT FERRANTE Sanitation Districts Assistant Chief Engineer

SOURCE - Winter 2016
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