Some Californians could see their water supply cut as much as 50 percent under new federal rules to protect threatened fish in the Sacramento-San Joaquin Delta.
The rules, released Monday by the U.S. Fish and Wildlife Service, govern water pumping operations by the California Department of Water Resources and U.S. Bureau of Reclamation. The agencies operate massive water diversion systems near Tracy that export Delta water for farm and urban purposes, from Silicon Valley to San Diego.
Two-thirds of Californians get at least some of their water from the Delta. It also irrigates nearly 3 million acres of farmland.
But these water diversions have pushed the Delta smelt, a fingerling fish native to the estuary, to the edge of extinction.
The new rules, called a biological opinion, were prepared under a federal court order that found existing regulations inadequate.
DWR estimated Monday that, in average weather years, the cuts could range from 20 to 30 percent. But in roughly one out of five years – typically a wet fall followed by a severe dry year – the cutbacks could reach 50 percent.
"This will have significant impacts in the agricultural community and it probably will start having an impact on economic development in urban areas because the water supply is becoming less certain," said DWR Director Lester Snow.
Conservation groups said they were pleased habitat concerns had triumphed over California water politics.
"By and large, the service appears to have issued a pretty good, scientifically supported plan that protects the Delta smelt while also being very conscious of the water supply impacts," said Doug Obegi, attorney at the Natural Resources Defense Council, a plaintiff in the 2006 lawsuit that prompted the new rules.
The rules stretch more than 400 pages and govern the complex interaction of California's many canals, pumps and dams. In short, they permanently change these operations to create better habitat.
In some cases, the rules require increased reservoir releases to cause more water to move freely through the Delta to the sea. In others, Delta pumping must be cut to avoid altering smelt habitat and breeding within the estuary.
"The amount of water 'lost' by this biological opinion can easily be made up by simple conservation measures," said Mike Sherwood, an attorney at Earthjustice, the legal firm that argued on behalf of environmental groups.
Water officials are particularly concerned about new controls on water operations in fall months to protect early smelt breeding activity.
Snow warned these fall regulations not only deepen the water cutbacks, but could limit the ability to provide adequate cold water releases from dams for salmon spawning in the subsequent year.
He said the ultimate solution is a habitat conservation plan, now being drafted, to cover several Delta species. This would supersede Monday's rules, but will take two years to complete.
"We don't view this as a permanent purgatory. It's a temporary purgatory," said Laura King-Moon, assistant general manager of the State Water Contractors.
Meantime, Snow said mandatory statewide conservation measures could be imposed if next year is dry. DWR also plans legislation to reach the governor's goal of 20 percent water conservation by 2020, announced earlier this year.
Call The Bee's Matt Weiser, (916) 321-1264. To comment on Delta issues, visit our reader forum at www.sacbee.com/delta
