Restrictions expected as early as June for Russian River water users as drought spurs new regulatory approach

State water regulators could begin suspending water rights in the Russian River watershed as early as next month as the drought extends into a third summer, intensifying water conservation needs in the region.

But curtailments are likely to affect fewer water diverters this year than last, when dangerously low reservoir levels forced state officials to freeze more than 1,800 water rights for landowners, water districts and municipalities to ensure minimal supplies remained in the two main reservoirs, especially Lake Mendocino, through fall.

The luxury of time has allowed this year’s plans to reflect a more refined, nuanced approach to cutbacks, based in part on public input, water regulators say. Their goal: to sustain base stream flows and stored supplies in a river system that is the lifeline for rural residents, farms and city dwellers in Mendocino and Sonoma counties.

That is no easy task this year, which began with three months that were the driest for any such winter period on record.

Lake Sonoma, the region’s largest reservoir, is at 58% of its seasonal capacity, lower than it was a year ago at this time.

Sharing water

Water regulators are optimistic a voluntary sharing agreement among those who pull supplies directly from the Russian River and some tributaries could stave off some pain.

If enough people participate, it would allow those with older, “senior” water rights to share their allotments with junior water right holders who otherwise would have their surface water diversions reduced or halted entirely, as happened on an unprecedented scale last year.

“The water rights priority system normally is all or nothing — you can use your water right or it can’t be used,” Sam Boland-Brien, supervising engineer with the State Water Resources Control Board, said in an interview Wednesday.

A sharing agreement, if broadly joined, “kind of lets everybody get through the drought together,” he said.

A new framework for emergency curtailments, approved unanimously Tuesday by the five-member water board, reserved space for that sharing agreement while also outlining a more precise way to hone cutbacks in the upper river based on differences in hydrology and demand.

A similar methodology was used to determine which of 300 water rights were curtailed in the lower watershed last year. But in the upper river, above the confluence with Dry Creek near Healdsburg, all 1,500-plus water rights were suspended, including those held by the cities of Cloverdale and Healdsburg, as well as grape growers, farmers and water districts.

Mendocino County Farm Bureau Executive Director Devon Boer was among those applauding the move Tuesday, calling it “a huge leap forward.”

Mendocino County landowners, who represented a large share of the users affected by last year’s crackdown, were grateful “looking at the draft regulation this year that geography wasn’t used as a (lone) curtailment guideline, especially for the upper reaches,” she told the water board.

The finalized regulation comes as the region — indeed, all of California — faces a third year of abnormally low rainfall, with each successive year compounding parched landscape conditions and pressure on already strained groundwater resources, a key supply in times of drought.

Where does the water go?

Water from the Russian River and its tributaries irrigates vineyards, food crops and pasture, while serving as a main source of drinking water for cities stretching from Ukiah in Mendocino County to Novato in northern Marin County. Sonoma Water, the region’s main wholesaler, distributes its supplies to more than 600,000 residents in Sonoma and Marin counties from riverside pumps near Forestville, downstream of Lake Sonoma.

Even more complicated is the system of water rights that dictates who gets to take water. It dates back more than a century, to an era before the onslaught of human-caused climate change and the more severe and persistent droughts already occurring as a result. The difficult decisions before regulators, who must determine that there’s enough water for some people and not for others, are tense endeavors, with serious economic impacts.

But when there is no natural flow in the river — only what’s released from Lake Mendocino and Lake Sonoma to sustain imperiled fish populations and recreational use — water rights holders no longer have the same rights. They can see their diversions reduced to 55 gallons per person per day for human health and safety needs.

The timing and extent of curtailments this year have been hard to predict and remain unclear in large part because of uncertainty about the status of inflows from the Eel River, a key supplemental source for the Russian River. The two systems are connected via a 114-year-old power plant in Mendocino County’s Potter Valley that PG&E is seeking to relinquish.

That water, which runs into a fork of the upper Russian River, feeding Lake Mendocino, is flowing at a comparably high rate, thanks to heavy October rains that raised the level of an upstream reservoir at the beginning of the water year, Boland-Brien said in an interview.

But PG&E has in recent years sought permission from federal energy regulators to lower the rate in order to meet its obligations to safeguard federally protected fish, and it is so far unclear if a request will be made this year and what it will include, Boland-Brien said. That call could have significant implications for how much water is available to users in the Russian River watershed.

The Eel River water is especially critical for farms, ranches, vineyards and thousands of rural residents along the upper river, in Mendocino County and northern Sonoma County.

The key reservoir for those users, Lake Mendocino, though only at 68% of its seasonal capacity, is in slightly better condition than it was a year ago, when the water level was the lowest ever for spring.

Boland-Brien said Wednesday that the state water board staff had expected to impose curtailments in May, but an April storm and splashes of rainfall since keep easing conditions just enough to forestall the inevitable.

Under the revised regulations, water rights holders will be required to track their status using the online Russian River Watershed Curtailment Status List and to comply with orders delivered there.

Another of this year’s revisions provides additional authority to the state water board staff to curtail diverters in four priority subwatersheds — Green Valley, Dutch Bill, Mark West and Mill creeks, strongholds for imperiled coho salmon and steelhead trout — even in the absence of other curtailments.

Additionally, those afforded the strongest type of water rights, known as riparian rights because their properties touch the river or a creek, will be required this year to provide a 12-month water use plan or default to an allocation based on their average 2017-19 usage.

Also new this year is language in the framework specifying that water obtained under the human health and safety exemption can be used to water outdoor food gardens or domestic livestock.

More information is available at waterboards.ca.gov/drought/russian_river/.

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

Editor’s note: This story has been corrected to reflect the number of water rights, not water right holders, affected by curtailments last year. A link to the Russian River Watershed Curtailment Status List also has been repaired.