The East Bay's largest water agency today will consider moving ahead on its plan to raise a Sierra dam, flooding a prime stretch of river to ease the grip of droughts.

The proposal is part of the East Bay Municipal Utility District's plan to secure additional water supplies through the year 2040. The district's directors are expected to approve the final environmental study today at a meeting in Oakland.

Water agency planners offered two alternatives —- either raise Pardee Dam on the Mokelumne River or build desalination plants with other Bay Area water agencies to ensure its 1.3 million customers never have to endure more than 10 percent water rationing in a drought.

"What we're trying to do is look down the road," said board director John Coleman. "We may find in this entire process (that the benefits) don't justify the cost of an enlarged Pardee. We may find that desalination will do it for us."

Critics contend that inundating a scenic and popular stretch of river is unwarranted.

"We can't drought-proof California," said Steve Evans, conservation director for Friends of the River. "When we have drought, people are going to have to cut back."

A final decision on whether to raise the dam is years away and will require additional environmental studies, but if the board adopts the plan as expected today, Evans said, environmentalists will have 30 days to sue.

The decision comes just months before the district expects to have access to water from the $1 billion Freeport project that it is building with Sacramento.

Freeport, which will draw water from the Sacramento River, is meant to shield residents from droughts. But EBMUD customers could still face 25 percent rationing in the most severe drought.

"To ask our customers to cut 25 percent after they've done all the things we've asked for was to be too much of a hardship," said district general manager Dennis Diemer.

Regulatory agencies that oversee salmon, land, water and the Mokelumne River have strongly criticized the environmental report.

  • The collapse of California's chinook salmon runs could require finding ways to allow salmon and steelhead to pass the district's Camanche and Pardee dams so they can spawn upstream, according to the National Marine Fisheries Service. Raising the dam, "doesn't support recovery of these fish," the service wrote to the district earlier this year.

  • The state agency that oversees water rights questioned whether the district really needs the water "in the near term" and noted that it already has unused reservoir space downstream of Pardee.

  • The stretch of the Mokelumne River that would be inundated if the dam has been declared suitable for inclusion as a wild and scenic river, the nation's highest level of environmental protection for a river in the nation, noted the U.S. Bureau of Land Management.

    The board meeting begins at 1:15 p.m. in EBMUD's board room at 375 11th St., Oakland.