Carlsbad Desalination Plant

Construction is underway on a desalination plant in Carlsbad, CA that will provide approximately 7% of San Diego region’s potable water by 2020 (construction completion expected in 2016).

Initial construction is estimated at $1 billion. Operating costs will be ~$50 million/year. The cost will be shouldered by San Diegans in the form of a $5-7 hike on monthly bills, even if households are not receiving water from the plant.

Private company Poseidon is building the plant. To offset their risk, they required The Water Authority (public utility) to sign an agreement to buy at least 48,000 acre-ft per year at the rate of $2,257 per acre-foot for the next 30 years (2). Up to 8,000 additional acre-ft may be purchased at $2,000 per acre-foot. Estimates vary, but most agree that at the start of operations, desalinated water will cost twice as much as sourcing water elsewhere. Poseidon claims that with rising costs of importing water, desalination will reach parity halfway through the 30-year contract (2). The Water Authority will have the option to buy the plant after 30 years for $1 (3). Poseidon will see a return of 9-17% on their investment; sources vary widely on this figure (4 & 8).

This will be the largest desalination plant in the western hemisphere, and twice the size of the current largest plant in America (a Florida plant built by Poseidon). A plant of comparable scope is in late planning stages for Huntington Beach, but is contested (9).

The plant uses the existing Encino Power Plant open ocean intake. Fish screens will will save 95% of juvenile fish, but only 20% of all organisms (2).

Despite efforts to make the plant energy efficient, it will still utilize vast amounts of energy – 38 megawatts per day, equivalent to 28,000+ homes (4).

Long Beach, Santa Cruz, Marin Municipal Water District, and water districts in San Francisco all considered desalination projects, but decided against them because they were cost-prohibitive, energy consumptive, and would negatively impact the environment (2 & 4).

Sources

1. Poseidon Water: “Carlsbad Project”
2. The Sacramento Bee: “Could desalination solve California’s water problem?” (Oct 18, 2014)
3. San Diego County Water Authority: “Water Authority Releases Proposed Carlsbad Desalination Water Purchase Agreement” (Sept 27, 2012)
4. San Jose Mercury News: “Nation’s largest ocean desalination plant goes up near San Diego; Future of the California coast?” (May 29, 2014)
5. U.S. Energy Information Administration: “Frequently Asked Questions”
6. U-T San Diego: “Carlsbad desal plant, pipe costs near $1 billion” (Jun 15, 2012)
7. Water-Technology: “Carlsbad Desalination Project, San Diego, California, United States of America”
8. YouTube: “Livia Borak of Coast Law Group speaks against Carlsbad desal project”
9. YouTube: “SoCal Insider (KOCE) on Poseidon” (Mar 23, 2013)
10. YouTube: “Dana Friehauf [of the San Diego Water Authority] describes how desalination fits into Water Authority’s diversification strategy” (Oct 2, 2012)

This is Part 2 in an ongoing series on water issues. Read Part 1.