Starting commercial production at the nation’s largest seawater desalination plant was among the most important events in the San Diego region’s centuries-long search for sustainable water supplies. The effort not only provided critical drought-resilient water supplies, but it also was honored locally and internationally as a visionary and cost-effective strategy for a vibrant region with few local drinking water resources.

The Water Authority also advanced other important aspects of its long-term water supply diversification strategy, finalizing an update to its Urban Water Management Plan and developing mitigation projects to support the landmark 2003 Colorado River Quantification Settlement Agreement. At the same time, the Water Authority continued providing regional leadership to ensure potable water reuse is the next major source of local water supplies.

Increasing Water Supply Reliability through Supply Diversification

  • Desalination Plant Dedicated with Dignitaries

    The Water Authority joined its partner Poseidon Water and more than 600 civic and business leaders December 14 to dedicate the Claude “Bud” Lewis Carlsbad Desalination Plant. It quickly began delivering approximately 50 million gallons per day, expanding the Water Authority’s supply portfolio yet again. It couldn’t have come online at a better time, as the region grappled with the fifth year of drought. The festivities – dubbed Pacific on Tap – included tours and speeches. State Assembly Speaker Toni Atkins said the project “not only provides San Diego County with a drought-proof water supply, it also demonstrates how California can meet the water needs of future generations.” The event was covered by media locally and around the globe.

    Desalination Plant Timeline


    Seawater desalination is officially recognized as a potential water supply in the Water Authority’s Urban Water Management Plan.


    The Water Authority Board identifies seawater desalination as the region’s best alternative for a new, reliable supply of water.


    State and local regulatory approvals clear the way for a desalination plant in Carlsbad.


    Water Authority Board approves landmark Water Purchase Agreement with Poseidon Water, launching construction.


    Claude “Bud” Lewis Carlsbad Desalination Plant dedicated, and commercial operations begin at the $1 billion project.

  • Historic Achievement Attracts Local, Global Accolades

    The Carlsbad desalination plant quickly generated regional and international acclaim. It was honored in April with a Global Water Award as the Desalination Plant of the Year by Global Water Intelligence for “the most impressive technical or ecologically sustainable achievement in the industry.” In June, the San Diego County Taxpayers Association recognized the desalination project with its highest honor – the Grand Golden Watchdog – for “stretching taxpayer dollars through cooperation between the public and private sectors.” The Water Purchase Agreement protected the region’s water ratepayers by shifting appropriate construction and operation risks to Poseidon, which in turn was assured of adequate sales to secure funding for construction and operation.

    Vice Chair Mark Muir
    Vice Chair Mark Muir accepted the Grand Golden Watchdog from the San Diego County Taxpayers Association on behalf of the Water Authority.
  • Water Plan Forecasts Efficiency, Supply Sufficiency

    San Diego County will continue to enjoy a safe and reliable water supply for decades under the Water Authority’s 2015 Urban Water Management Plan adopted in June. The plan anticipates demands through 2040 will be met through continued development of highly reliable, locally controlled water supplies such as recycling, reuse and groundwater recovery – and less reliance on imported supplies from the Metropolitan Water District. In addition, the plan forecasts that water demands will be about 13 percent lower in 2020 and about 12 percent lower in 2035 than in the prior plan’s forecast, due to updated demographic and economic projections driven by the Great Recession and long-term improvements in water-use efficiency by residents and businesses.

  • Advocating to Advance Potable Reuse

    The Water Authority continued to take a leading role in potable reuse issues statewide, completing focus group research to support outreach efforts, providing input to the state’s expert panel on potable reuse regulations and informing a feasibility study by the State Water Resources Control Board. In addition, the San Diego Integrated Regional Water Management Program – managed by the Water Authority along with the City of San Diego and County of San Diego – provided state grant funds to support three potable reuse projects: Padre Dam Municipal Water District’s Advanced Water Purification demonstration project, the City of San Diego’s Pure Water demonstration project, and a research initiative by the Water Environment & Reuse Foundation in San Diego.

    By 2035, potable reuse is expected to meet about 16 percent of the region’s water demands as the next major increment of local water supply. The process includes multiple treatment technologies to purify wastewater for drinking, cooking and other uses.
  • Securing State, Federal Action at the Salton Sea

    Along with its partners in the Quantification Settlement Agreement Joint Powers Authority, the Water Authority helped generate more momentum for solutions at the Salton Sea than at any time in the past decade. The Water Authority successfully advocated for Gov. Jerry Brown to create a task force to identify shovel-ready restoration projects at the sea, and it successfully lobbied for state bond money to start funding the projects. In all, the Joint Powers Authority spent more than $20 million during the fiscal year on environmental mitigation at the sea, including mitigation water flows and air quality pilot projects. The Water Authority also contributed funds for early-stage construction of the Red Hill Marina Wetlands, a 450-acre habitat project.

    The Water Authority has met all of its financial commitments at the Salton Sea since 2003 and is in compliance with all state and federal environmental obligations. Most of that funding has gone toward providing bucket-for-bucket mitigation water to the Salton Sea from 2003 through 2017 to eliminate any impact of the water transfers on the sea’s shoreline.
  • Water Sources & Uses

    Water Sources And Uses

    Fiscal Year 2016

    Compilation of data furnished by member agencies

    Source of Water
    Member Agency Local Supply1 (Acre-feet) Water Authority Supply2 (Acre-feet) Total (Acre-feet)
    Type of Water Authority Supply
    Agricultural Use3 (Acre-feet) M&I Use (Acre-feet)
    Gross Area (Acres) Estimated Population
    Carlsbad M.W.D. 3,721.5 13,669.0 17,390.5 - 13,669.0 20,682.0 86,596
    Del Mar, City of 117.0 899.2 1,016.2 - 899.2 1,442.0 4,257
    Escondido, City of 1,044.1 17,474.2 18,518.3 2,335.4 15,138.8 21,569.0 134,053
    Fallbrook P.U.D. 706.1 9,468.4 10,174.5 3,038.9 6,429.5 27,988.0 35,000
    Helix W.D. 1,792.6 25,324.9 27,117.5 - 25,324.9 31,350.0 271,759
    Lakeside W.D. 816.1 2,368.9 3,185.0 - 2,368.9 11,488.0 35,500
    National City, City of 2,682.1 2,331.5 5,013.6 - 2,331.5 4,812.4 59,408
    Oceanside, City of 3,107.4 19,681.3 22,788.7 323.4 19,357.9 26,982.5 174,522
    Olivenhain M.W.D. 2,157.4 16,009.9 18,167.3 84.2 15,925.7 30,942.1 84,352
    Otay W.D. 3,627.2 25,500.7 29,127.9 - 25,500.7 80,320.0 220,213
    Padre Dam M.W.D. 742.6 8,628.8 9,371.4 221.7 8,407.1 54,402.2 88,895
    Camp Pendleton4 6,089.5 187.5 6,277.0 - 187.5 134,625.0 65,000
    Poway, City of 454.2 8,351.5 8,805.7 34.7 8,316.8 25,047.0 48,774
    Rainbow M.W.D. - 17,049.7 17,049.7 7,845.9 9,203.8 47,670.0 19,944
    Ramona M.W.D. 622.4 4,244.2 4,866.6 1,030.1 3,214.1 45,868.0 33,360
    Rincon Del Diablo M.W.D. 2,760.9 4,727.2 7,488.1 22.8 4,704.4 10,596.1 29,955
    San Diego, City of5 16,738.1 147,490.3 164,228.4 130.9 147,359.4 213,121.0 1,391,676
    San Dieguito W.D. 2,055.8 3,839.0 5,894.8 - 3,839.0 5,659.8 37,376
    Santa Fe I.D. 2,389.6 6,092.0 8,481.6 - 6,092.0 10,359.0 19,400
    South Bay I.D. 2,069.0 9,917.6 11,986.6 - 9,917.6 13,836.9 128,888
    Vallecitos W.D. 1,750.0 11,235.4 12,985.4 816.8 10,418.6 28,334.0 99,796
    Valley Center M.W.D. 368.4 19,656.7 20,025.1 12,950.0 6,706.7 64,540.0 25,608
    Vista I.D. 1,582.4 14,229.7 15,812.1 44.3 14,185.4 21,158.4 124,746
    Yuima M.W.D. 5,566.1 3,625.3 9,191.4 2,816.5 808.8 13,460.0 1,870
    Totals6 62,960.5 392,002.9 454,963.4 31,695.6 360,307.3 946,253.4 3,220,948
    • 1 Includes surface, recycled, groundwater and seawater desalination supplies; does not reflect conserved water.
    • 2 Water use in a given year may differ from Water Authority water sales due to utilization of storage.
    • 3 Includes only amounts certified through the Transitional Special Agricultural Water Rate (TSAWR) discounted agricultural water use program.
    • 4 Includes Water Authority deliveries via South Coast Water District system.
    • 5 Excludes City of San Diego local surface water use outside of Water Authority service area.
    • 6 Numbers may not total due to rounding.
  • Water Use By Sector

    Chart showing Water Use by Sector - 74,048 TAF (16%) Commercial & Industrial, 44,675 TAF (10%) Agriculture, 39,589 TAF (9%) Public & Other, 296,380 TAF (65%) Residential

Rainfall Totals for October 2015 - September 2016

Figures in inches