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 water rights for more than 1,800 landowners, water districts and municipalities to ensure minimal supplies remained in the two main reservoirs, especially Lake Mendocino , through fail.
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, unanimously approved 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, water rights were suspended for all 1,500-plus diverters, including 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 patched 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.