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.


  • Nation’s Largest Seawater Desalination Plant Marks One-Year Anniversary

    FOR IMMEDIATE RELEASE Contacts: Jessica Jones Poseidon Water (760) 655-3998 

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    Nation’s Largest Seawater Desalination Plant Marks One-Year Anniversary 

    Carlsbad, CA (Dec.14, 2016) – In its first year of operations, the nation’s largest and most technologically advanced seawater desalination plant produced enough high-quality, drought-proof water from the Pacific Ocean to meet approximately 10 percent of the region’s demand. The Claude “Bud” Lewis Carlsbad Desalination Plant quickly generated significant benefits by relieving pressure on imported water supplies, reducing state mandates for emergency conservation measures in March and helping the region pass the state’s stringent water supply “stress test” in June. Read more.

  • DBIA Announces 2016 Design-Build Project of the Year

    FOR IMMEDIATE RELEASE: Contact: Louis J. Jenny, Design-Build Institute of America (202) 454-7507
    Carlsbad Desalination Plant Honored as Project of the Year

    Las Vegas, Nevada, 2016 – The Design-Build Institute of America (DBIA), the only organization that defines, teachesand promotes design-build best practices, announced the 2016 Project of theYear and National Award of Excellence winners at the Design-BuildConference & Expo Awards Dinner. Read more.

  • Poseidon Water Named Energy Champion by SDG&E

    FOR IMMEDIATE RELEASE Contact: Jessica Jones (760) 655-3998   download a pdf
    Recognized for accomplishments in reducing energy consumption at the Carlsbad Desalination Facility

    Carlsbad, CA (July 11, 2016) - San Diego Gas & Electric (SDG&E) named Poseidon Water an “Energy Champion” for 2016. Poseidon was selected as the Water Energy Nexus Champion for their investments in, and commitment to, sustainability and energy efficiency at the Claude “Bud” Lewis Carlsbad Desalination Plant (the Plant).  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.