State regulators are asking about 650 landowners along Sonoma County’s four major coho salmon spawning streams to voluntarily reduce water diversions to protect the drought-imperiled fish species, which is hanging on after nearly going extinct in the Russian River two decades ago.
Letters issued jointly by the State Water Resources Control Board and the California Department of Fish and Wildlife were mailed this week to the landowners — primarily rural residents as well as some grape growers — along Dutch Bill and Green Valley creeks in the west county, Mark West Creek north of Santa Rosa and the Mill Creek system west of Healdsburg.
Survival of the coho is “at a precarious junction” in the fourth year of “the worst drought in recorded California history,” read the letter, signed by Scott Wilson, a regional manager with the wildlife agency, and Barbara Evoy, deputy director of the water board’s division of water rights.
“Every week is critical for these endangered salmon,” the letter stated, outlining steps — including use of alternative water sources, curbing lawn irrigation, installing low-flow household devices such as toilets and washing machines and releasing spare reservoir water — to maintain stream flows from May 1 through November or later.
“The fish need a minimum amount of water flow to live and these steps and cooperation are necessary for them to succeed,” the letter said.
The move amounts to the agencies’ first drought-related action this year on local stream use. It seeks voluntary commitments from 654 landowners to cut back on water drawn from coho breeding streams feeding into the Russian River. But the letter also warns that if voluntary actions are insufficient, the state could halt water diversions, a step known as curtailment that was imposed last year on the upper Russian River and other dwindling waterways on the North Coast and in the Central Valley.
No specific level of conservation was cited in the letter.
“We’re asking for whatever you think you can do to save some fish,” said Andrew Hughan, a wildlife agency spokesman. “If you need 500 gallons a day, can you try it with 450?” he said. “If you can’t, then you can’t.”
Asked how officials will determine if the voluntary cutbacks are working, Hughan said officials will survey the streams to determine whether there is sufficient cold water with fish in it. “There’s no other way to do it,” he said.
Water conservation along the creeks will be needed “until it rains again,” he said.
Tito Sasaki, chairman of the Sonoma County Farm Bureau’s water committee, said the request for voluntary conservation is better than state-mandated curtailments.
“You could say it a hundred times,” said Sasaki, a Sonoma Valley grape grower. “We don’t want to go under their hammer.”
Last year’s curtailments, imposed in May, suspended water rights for about 650 permit holders on the Russian River north of its confluence with Dry Creek near Healdsburg, forcing some growers to haul thousands of gallons of water to irrigate crops. The curtailments were lifted in November.
New curtailments for this year were imposed Thursday on some water rights holders in the San Joaquin River watershed, in the Central Valley.
“Curtailment is on the table” for Sonoma County due to the coho’s protected status, Hughan said.
Sasaki said he didn’t know how much water grape growers are diverting from the creeks at this time of year. Most growers use drip irrigation, drawing on reservoirs filled either with groundwater or stream flow, he said.