Water distribution system

Officials announced Tuesday that they are allowing water managers to send more Northern California water south. The move comes as fishery agencies are under increasing political pressure to take advantage of late winter storms and ramp up pumping from the Sacramento-San Joaquin delta, the center of the state’s water distribution system. (Randall Benton / MCT / April 10, 2013)

Officials announced Tuesday that they are temporarily waiving an endangered species protection to enable water managers to send more Northern California water south.

The move comes as fishery agencies are under increasing political pressure to take advantage of late winter storms and ramp up pumping from the Sacramento-San Joaquin Delta, the center of the state's water distribution system.

Mark Cowin, director of the state Department of Water Resources, said the rule suspension would remain in effect for the next week or two and would increase delta exports by as much as 10,000 acre-feet a day. An acre-foot is equivalent to a year's water supply for two households.

This marks the second time in less than a month that fishery agencies, responding to the drought, have relaxed a seasonal environmental restriction on delta pumping.

Environmentalists condemned the action.

"The increased pumping authorized today sacrifices California salmon runs and is terrible news for the thousands of men and women whose livelihoods depend on a healthy delta," said Doug Obegi, an attorney with the Natural Resources Defense Council.

The changes are unlikely to help most of the state because the additional exports will either be kept in storage south of the delta as a hedge against another dry year, or they will go to irrigation districts with senior water rights. Most growers supplied by the federal Central Valley Project have been told they won't get any deliveries this year.

"We don't see that those numbers would go up from zero," said David Murillo, regional director of the U.S. Bureau of Reclamation, which operates the project.

State officials have also projected a zero allocation for all but senior rights holders in the State Water Project, which helps supply the urban Southland. The water resources department will decide this month if conditions have improved enough to allow minimal deliveries to all contractors.

Pumping restrictions imposed under the Endangered Species Act vary from season to season and change according to how wet or dry the year is. Normally, a limit would go into effect April 1 to protect salmon and steelhead migrating through the delta.

William Stelle, regional administrator of the National Marine Fisheries Service, said his agency decided to grant the state's request for a waiver after concluding that enough other protections remained in place.

"We are being careful in what we do to make sure the adjustments we are making are based on sound science," he said. "We think we can justify them and defend them successfully."

Late winter storms have improved the Sierra Nevada snowpack, but it is still only about a third of the norm for the date. That is up from 24% a month ago and the abysmal 12% measured in late January. At 61% of average, precipitation in the Northern Sierra, a key source of water, has also climbed out of the basement.

That has helped boost levels of the state's two largest reservoirs, Shasta Reservoir and Lake Oroville in Northern California. But both remain slightly less than half full and state officials expect that this year will be among the 10 driest on record.

bettina.boxall@latimes.com