With little prospect of significant rain for the rest of the year, the Sonoma County Water Agency is preparing to ask the state for permission to slash the amount of water it releases into the Russian River in hopes of preserving the dwindling reserve in Lake Mendocino.
"We need to get out in front of this; the data (points) don't lie ... We're looking at some of the driest conditions in recent records," said Supervisor Mike McGuire, who represents the northern end of the county, which would be directly affected by reduced river flows. The supervisors also serve as the board of directors of the Water Agency.
Agency staff will meet with staff from the State Water Resources Control Board as early as today to see how far the state will allow it to cut back its water releases, which are governed by a state permit. The agency expects to file a formal request within the next two weeks.
Since the start of the year, the county has had less than 8 inches of rainfall as measured in Santa Rosa. Normally, that figure should be around 33 inches. So dry are the conditions statewide that state and federal lawmakers sent letters last week to Gov. Jerry Brown, asking him to declare a drought emergency, and to President Barack Obama, asking for a federal disaster declaration.
Water managers are comparing conditions to those in 1976 and 1977, the most severe modern drought in the region, McGuire said. That drought forced widespread mandatory restrictions on water use and led local governments throughout the area to develop aggressive voluntary water conservation programs that remain in place today.
There is no immediate threat of water rationing, the agency says, largely because the main reservoir at Lake Sonoma is still about 70 percent full, plenty to provide water for its 600,000 customers in Sonoma and Marin counties through at least one more dry year.
But upstream, the smaller and more volatile Lake Mendocino is down to only about 30 percent of its capacity. If the agency maintains its current release rate and the winter turns out to be critically dry, water managers could find themselves with no water to release next summer, spelling major trouble for the cities, farmers and wildlife that rely on the upper reaches of the Russian River — those areas north of where the Lake Sonoma water supply enters the river at Dry Creek.
"We have to plan for the long term" in restricting flows now, McGuire said.
It's not clear exactly how much the agency will ask to cut back the water releases; that is a detail staff will hash out at this week's meeting. As of Friday morning, the river at Healdsburg was flowing at about 115 cubic feet per second, or about 860 gallons per second.
The agency already has permission to drop that flow rate to as little as 75 cubic feet per second. Assistant General Manager Pamela Jeane said the agency has begun restricting the flow in the past week.
The agency would like permission to drop the flow lower than 75 cubic feet per second if necessary, possibly as low as 25, the lowest allowed under the permit. It is unlikely, however, that the agency would ask, or even get permission, for a level as low as 25, she said.