California boasts the eighth-largest economy in the world and technology prowess that helped develop—among many other things—desalination in the 1950s. The Golden State also has more than 800 miles of coastline with limitless supplies of seawater from the Pacific Ocean.
But a combination of economic, environmental and regulatory hurdles remain before widespread use of desalination can be fully realized and help make a dent in the drought-stricken state's water shortage.
"Ocean desal is pretty expensive still," said Ellen Hanak, senior fellow at the San Francisco-based Public Policy Institute of California and director of the Institute's Water Policy Center. "It's probably the most expensive single source that an urban agency can use, but its advantage is it can be reliable, since there's a lot of ocean water out there."
Experts say the energy-intensive process to remove salt from ocean water means desalination water can cost double the amount of water that comes from recycling wastewater or building new reservoirs. What's more, the cost to build and operate desalination plants is high, and the state of California is unlikely to fund all such projects, although several affluent coastal cities such as Santa Barbara and Cambria have moved forward with plans of their own.
"Energy is a major cost component of a desalination plant," said Heather Cooley, water program director for the Pacific Institute, an Oakland-based non-profit that focuses on water issues. "And so the cost of energy has a major impact on the cost of water that's proposed."
Currently, seawater and brackish water desalination is estimated to contribute less than 1 percent of California's drinking water. The most common desalination used in the state is not from seawater but from brackish groundwater that's processed in desalting plants located in some of the state's largest urban areas.
Currently there are more than 20 operating groundwater desalting facilities statewide. At last count, there were another 16 groundwater desalination plants proposed or in the works, according to California Department of Water Resources.