Q: Water shortages in California and the West will be a fact of life forever. Why is there not a single desalination plant anywhere on the coast? Why don’t San Francisco, Carmel, Santa Barbara, Los Angeles and San Diego have such facilities? – Joe Whiten, Sacramento
A: Desalination – the process of removing salt from water – is expensive. It takes more energy to desalinate water from the ocean than to obtain it from most other sources, according to the Pacific Institute, a nonprofit environmental policy research group.
Desalination plants contain pipes that can trap marine organisms, harming the ocean’s ecosystem, according to a recent LA Times op-ed by David Helvarg, executive director of Blue Frontier, an ocean conservation group. The plants also produce heavy salt brine, which can be hard to eliminate back into the ocean without hurting the environment.
“A lot of really salty water could devastate estuaries,” said Robert Glennon, author of Unquenchable: America’s Water Crisis and What To Do About It.
Many cities and water districts have looked at those fiscal and environmental costs over the last few decades – and balked. But a few are giving it a try.
The San Diego Water Authority plans to buy large amounts of water from a huge desalination plant under construction in Carlsbad. It is betting that the costs of desalination will fall while the expense of obtaining water through other means will rise.
Helvarg and Glennon said environmental problems associated with desalination could be mitigated –again at a cost. Both said desalination will not erase the state’s water issues, but could become a part of a broader solution.