Lower flows in Russian River sought to protect supply in Lake Mendocino

Desperate to save plummeting water reserves in Lake Mendocino, a Mendocino County water agency is lobbying the state to dramatically reduce the amount that must be released downstream into the Russian River for fish and people.

Without a change to the current release schedule, and barring a wet fall, the reservoir is set to be nearly dry by the end of the year, Mendocino County water officials said.

“We want to make sure we take every action possible to avoid an impending disaster,” said Sean White, director of the Russian River Flood Control and Water Conservation Improvement District, which is seeking the change. The district holds Mendocino County’s right to 8,000 acre-feet of water in the lake.

Officials with the state Water Resources Control Board said Thursday they are considering the request.

It comes as Lake Mendocino - the largest reservoir on the upper Russian River and a major summer source of water for fish, residents and farmers along the section of river north of Healdsburg - is at less than 38 percent of capacity, or 42,000 acre-feet. Mandated releases, largely for fish, are causing the lake to lose about 200 acre-feet a day.

Mendocino officials are hoping to reduce that amount by cutting the downstream releases by two-thirds, from 75 cubic feet per second to 25 cubic feet per second at a measuring point near Healdsburg. The amount of water saved under such a change would be roughly 100 acre-feet a day, enough to supply 300 families for a year, White said.

“It’s not good for anybody to run out of water - fish or people,” he said, adding that keeping more water in the reservoir also would help fish later in the year.

The district is aiming to protect its supply for customers in the Ukiah and Hopland valleys.

The request to the state is to change its designated water supply conditions for Lake Mendocino, which now is being managed for a “dry year.” The Russian River water district wants the designation changed to a “critically dry year.” A similar temporary change was granted by the state in 2009.

The request comes amid a now extended drought that has imperiled water supplies throughout the state, prompting mandatory cuts for farmers and urban customers and spurring water managers to conserve the dwindling reserves they now have behind dams and in streams.

The upper Russian River, between its confluence with Dry Creek near Healdsburg and Lake Mendocino, is one of the most impacted rivers in the state. Farmers along the upper Russian have had their junior water rights curtailed and the cities of Cloverdale and Healdsburg, which rely on the river and the wells it supplies for drinking water, were some of the first in the region to implement mandatory conservation measures this year.

The request by the Russian River Flood Control and Water Conservation Improvement District is another reflection of deepening impact of the drought on the region.

White, the district director, said the entreaty to the state is a long shot because his district doesn’t have the legal standing to make a formal request. That authority lies with the Sonoma County Water Agency, which owns most of Lake Mendocino’s water and is charged with managing the releases during the dry season. The Army Corps of Engineers manages flows in the winter.

White said his board has asked the Sonoma agency to make a formal request, but it has not yet done so.

“We are considering asking the water board for a temporary change,” said Sonoma County Water Agency spokeswoman Ann DuBay.

She said it’s a complicated issue that affects all downstream water users and cannot be taken lightly. For example, people with groundwater wells recharged by the river might see decreases in water production, she said.

White said the state water board also should consider permanent changes to its Decision 1610, the 1986 document that sets out the rules for minimum flow requirements in the Russian River. The document aims to balance the needs of people and public resources, like fish.

The current water releases are based on June 1 water levels in Lake Pillsbury at the headwaters of the Eel River. Some Eel River water is shunted down a tunnel into a Potter Valley power plant, before heading to Lake Mendocino.

That supply once kept Lake Mendocino healthy through the summer months, but it was significantly decreased in 2004, an effort aimed at benefiting Eel River fish.

It no longer makes sense to have the releases from Lake Mendocino dependent on Lake Pillsbury, White contends. A separate request filed by the Sonoma County Water Agency with the state seeks a permanent alteration in the schedule.

“It’s kind of like having your budget tied to your neighbor’s income,” White said.

You can reach Staff Writer Glenda Anderson at 462-6473 or glenda.anderson@pressdemocrat.com. On Twitter @MendoReporter.