Regulators approve emergency rules to allow halt of Russian River diversions for thousands of water right holders

The state water board has unanimously approved emergency regulations behind a move to halt Russian River diversions for up to 2,400 water right holders, part of a wider effort to conserve dwindling supplies in Lake Sonoma and Lake Mendocino.

The 5-0 vote of the State Water Resources Control Board late Tuesday came over the objections raised by agricultural interests and allies who argued the new rule was too blunt a tool to use to address the worsening drought.

Hundreds of Sonoma and Mendocino county grape growers, ranchers, rural residents and even some municipal suppliers are on notice that they could have their rights suspended under the move.

Already, about 930 water right holders in the upper river, north of Healdsburg, have been told there is insufficient water in the system for them to take any this year.

As the region’s prolonged dry season sets in, water managers say the crisis threatens to sap meager flows in the upper river and drain Lake Mendocino, the smaller of the basin’s two main reservoirs, by winter.

Members of the state board said they had no better way to safeguard the region’s drinking water supplies. The Russian River is the main source for more than 600,000 residents in Sonoma and northern Marin counties. Towns from Healdsburg north to Ukiah, in Mendocino County, also draw from the river to supply homes and businesses.

“The seriousness of the situation is such that, absent action now, we may not prevent wholesale communities from running out of water,” said state water board Chairman E. Joaquin Esquivel. “If we wait, we’ll be well into the fall before we act and well beyond the window of being able to do so.”

Close to 660 more rights holders in the upper river have been warned their diversions could be curtailed under the emergency regulation, which is not expected to go into effect until around July 5, after a public comment period and administrative processing by the Office of Administrative Law.

Another 800 water right holders in the lower river, below the confluence of Dry Creek, the outlet for Lake Sonoma, also could be affected by the new regulation. That action could come much later, board personnel said.

Timing of the crackdown on diversions in the upper river depends on how quickly the supplies in Lake Mendocino drop and the effect on flows below Coyote Dam. A minimum amount must be kept in the river to sustain imperiled salmon and steelhead trout.

In the meantime, the immediately affected 930 water right holders on the upper river can no longer pull from the river, with penalties for those who don’t comply. Use of supplies that were previously diverted and stored is allowed.

Farming interests have pushed for more detailed hydrological data from the watershed. They also questioned the methodology used to calculate the source of water in the river and user demand basin-wide.

But the jeopardy is apparent for all to see in the receding shorelines of Lake Mendocino and Lake Sonoma, which are at their lowest levels ever this early in the year. Lake Mendocino, at the upper end of the basin, is at about 38% and Lake Sonoma, which holds far more water, is at 55%.

The hot and dry months ahead are poised to sharply diminish storage through evaporation and increased withdrawals.

A number of moves are underway to conserve those supplies.

On Monday, the region’s main water wholesaler, Sonoma Water received permission from the state to immediately cut stream flows in the lower Russian River by more than half to retain more summertime water in Lake Sonoma.

The state decision means the county agency and its contractors — the cities of Santa Rosa, Sonoma, Rohnert Park, Windsor, Petaluma and Cotati, and the Valley of the Moon, Marin Municipal and North Marin water districts — will have to use 20% less water from the Russian River, as well.

Sam Boland-Brien, a supervising engineer for the state water board, said 125 of of 142 letters sent to the board on the emergency rules were supportive of the regulation.

Some critics nonetheless hinted during Tuesday’s meeting that any action would be subject to court challenge. They argued with the details of the legal justification, as well.

“There is a better way,” said Phil Williams, special counsel to the city of Ukiah, a water rights holder on the upper river. It has other sources on which it can draw to supply residents.

Many who objected took issue with language underlying the regulation that allows the board to take emergency action to prevent the “waste and unreasonable use” of water during critically dry periods.

Even though the word “waste” was stricken from the draft documents during Tuesday’s meeting, those worried about losing the right to irrigate vineyards or other crops or water livestock viewed the terms as offensive and inflammatory.

The water board’s chief legal counsel, Michael Lauffer, said the language and utilization of the Water Code section at issue was not meant as an affront to agriculture but was necessary to allow state regulators to bypass the water rights system.

That system generally gives older, “first-in” senior claims priority over younger rights, while aiming to preserve enough supply for health and human safety.

Several stakeholders on the upper river said a monthslong effort to work out voluntary conservation measures among senior and junior water rights holders had not been given enough time to succeed.

Water board staffers working with the group found it promising at first. But the intensifying drought and danger of Lake Mendocino going dry prompted the emergency action, regulators said.

The collaborative efforts can continue, officials said, and could forestall curtailments if they prevent Lake Mendocino from dropping below threshold levels.

A resolution included in the emergency action Tuesday voiced support for such efforts.

But even Vice Chairman Dorene D’Adamo, who was wary about the emergency rule throughout Tuesday’s hearing, said she would support the measures. She said she wished there was another way.

“I do feel strongly that we need to act today to stop the bleeding,” she said.

You can reach Staff Writer Mary Callahan at 707-521-5249 or mary.callahan@pressdemocrat.com. On Twitter @MaryCallahanB.