Project Overview

The Claude "Bud" Lewis Carlsbad Desalination Plant is a 50 million gallon per day (56,000 acre-feet per year (AFY)) seawater desalination plant located adjacent to the Encina Power Station in Carlsbad, California. Desalination has evolved into a desirable water supply alternative by tapping the largest reservoir in the world - the Pacific Ocean. The technology, available for decades, is at work in many arid areas of the world including the Middle East, the Mediterranean and the Caribbean. A 30-year Water Purchase Agreement is in place between the San Diego County Water Authority and Poseidon Water for the entire output of the plant. The plant has been delivering water to the businesses and residents of San Diego County since December 2015.


  • Southern California Desalination Plant will Ease Water Crunch, but Price is Steep

    Sacramento Bee

    Carlsbad, CA (December 12. 2015) - The newest weapon in the war on drought in California has arrived, an engineering marvel that will harvest drinking water from the ocean on a scale never before seen in the Western Hemisphere. A giant water desalination plant will open this week north of San Diego, tucked behind a power plant across the street from Tamarack State Beach. Read more. 

  • Editorial: In Celebration of Water: Carlsbad Desal Plant Opens

    San Diego Union Tribune

    Carlsbad, CA (December 12, 2015) - It’s been there all along, the largest reservoir in the world, lapping at our shore but unavailable through drought after drought. Finally, on Monday, politicians and government officials, business leaders and residents will gather in Carlsbad to dedicate a $1 billion plant and pipeline connecting the Pacific Ocean to the San Diego County drinking water network. It is in many ways a remarkable and historic achievement. Read more.

  • Desalination Comes of Age

    Carlsbad, CA (October 19, 2014) - Water, water everywhere, nor any drop to drink. That line is all that remains in my brain from an early exposure to “The Rime of the Ancient Mariner,” the endless poem that has been cruelly inflicted upon generations of American school children. Read more.

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State, regional and local water plans all have confirmed that immediate and pressing water needs cannot be accomplished without some investment in seawater desalination.

  • The plant will provide 56,000 AFY of new water supply for the San Diego region. A region where nearly 85% of the current water supplies are imported.
  • The CA Department of Water Resources’ 2009 Water Plan Update identifies the need for 275,000 AF of desalinated water by 2025.
  • The Metropolitan Water District of Southern California’s Integrated Water Resources Plan identifies a need for 150,000 AFY of seawater desalination (including 56,000 AFY from the Carlsbad project) by the year 2020.
  • The San Diego County Water Authority’s (SDCWA) Urban Water Management Plan identifies a need for 56,000 AFY of seawater desalination from the Carlsbad project by 2016.