By Sharon Bernstein
SACRAMENTO, Calif. (Reuters) - California water regulators on Wednesday adopted a new uniform permitting process for seawater desalination projects expected to expand in number as the drought-stricken state increasingly turns to the ocean to supplement its drinking supplies.
Action on the desalination rule, which puts key decisions for such plants in the hands of statewide regulators rather than regional boards, came a day after the same state body enacted sweeping cutbacks in water use by California's cities and towns.
The latest measure amends California's Ocean Plan to make clear that regulators must evaluate the best available sites, designs, technologies and mitigation measures for minimizing harm to the environment from desalination plants.
It also sets a standard limit for the discharge of desalination's waste byproducts back into the ocean, and imposes monitoring and reporting requirements for the discharges.
The rule, approved by the State Water Resources Control Board in Sacramento by voice vote, applies to all newly built or expanded treatment facilities designed to make seawater drinkable.
Desalination has emerged as a promising technology in the face of a record dry spell now gripping California for a fourth straight year, depleting its reservoirs and aquifers and raising the costs of importing water from elsewhere.
San Diego County, Santa Barbara and other local jurisdictions are now pushing ahead with seawater desalination plants.
But critics have cited ecological drawbacks, such as harm to marine life from intake pipes that suck water into the treatment systems and the concentrated brine that gets pumped out.
The Western Hemisphere's biggest desalination plant, a $1 billion project under construction since 2012 in the coastal city of Carlsbad, California, is due to open in November.
It will deliver up to 50 million gallons (190 million liters) of water a day to San Diego County, enough to supply roughly 112,000 households, or about 10 percent of San Diego County's drinking water needs, according to the company behind the project.
Approval is being sought for a final permit to begin construction of a second plant of similar size in Huntington Beach, south of Los Angeles, next year.
On Tuesday, the state water board enacted California's first rules for mandatory statewide cutbacks in water use. The emergency regulations, which require some communities to trim water use by as much as 36 percent, were approved unanimously just weeks after Democratic Governor Jerry Brown stood in a dry mountain meadow and ordered statewide rationing.
(Reporting by Sharon Bernstein; Writing and additional reporting by Steve Gorman in Los Angeles; Editing by Bill Trott and Mohammad Zargham)