Despite flush reservoirs, Sonoma County water officials stress need for conservation
As California confronts its fourth year of drought and the window for any significant spring rainfall closes, the North Coast has more water in storage than a year ago and is in better position than much of the state to meet its supply needs during the traditionally warm, dry months ahead.
Having endured a near-rainless January and a fourth consecutive winter with below-normal rainfall, local residents can thank several drenching days in December and February for bringing season-to-date rainfall to nearly 24 inches - the most in four years and just 8 inches shy of average for this date.
The total was enough to officially downgrade the drought in most of Sonoma County and all of Mendocino County from “extreme” to “severe,” according to the U.S. Drought Monitor federal index and map program. With the Sierra Nevada snowpack at a record low, two-thirds of the state remains in a state of “extreme” or “exceptional” drought.
That’s not to say, however, that the crisis is over on the North Coast, experts said. The strain on groundwater - the other major local source aside from reservoirs - has managers especially concerned. Pumping, by farmers especially, has outpaced groundwater replenishment from rainfall across much of the state. Sonoma County’s aquifers, while not as heavily tapped as those in the Central Valley, for example, are still under significant pressure. Conservation will continue to be key, water managers said.
“We’re not out of this thing by any stretch of the imagination, that’s for sure,” said Jay Jasperse, chief engineer and director of groundwater management for the Sonoma County Water Agency, wholesale supplier to more than 600,000 people in Sonoma and Marin counties.
The region’s main reservoir, Lake Sonoma, fed by a tributary to the Russian River, has more than 216,000 acre feet of water in storage, or about 88 percent of its water supply capacity. Last year at this time, the reservoir was at 72 percent of its capacity, according to the state Department of Water Resources.
To the north, at smaller Lake Mendocino, storage is nearly 65,000 acre feet, or 79 percent of water supply capacity. Last year at this time, it was at roughly 47 percent, according to state records.
The improved storage outlook is expected to provide some cushion - for drinking water, farming and recreational uses - but it’s important to remember that the benchmark this spring follows two exceptionally dry years, water officials said.
“It’s better than last year, but last year was very, very bad,” Jasperse said.
“We basically bought ourselves six months of breathing room,” Don McEnhill, director of the group Russian Riverkeeper, said of the few good winter storms - what meteorologists now call “atmospheric river events.”
“We’ll probably get through the summer,” said McEnhill, a veteran waterman who spends many hours paddling boats on the Russian River.
Emily Chase, office manager at SOAR Inflatables/Russian River adventures in Healdsburg, said even with less rain last year, her company ran trips through mid-November, the latest ever.
With more rain this year, “We’ll see what happens, but we’ll be running trips all season for sure,” she said.
Still, McEnhill and others warned against the kind of complacency evident in urban consumption figures released March 3, which demonstrated a steep decline in statewide conservation efforts once the December rains appeared and January rains did not.
While some cities, including Santa Rosa, Rohnert Park and the Mendocino County community of Redwood Valley, continued to conserve - using at least 20 percent less water than they did in the previous January, and meeting a reduction goal issued last summer by Gov. Jerry Brown - many other communities on the North Coast and statewide saw their consumption shoot up. The trend resulted in a shift from December, when water consumption statewide fell by 22 percent from December 2013, to a year-over-year January savings of just 8.8 percent, according to the state Water Resources Control Board. (The numbers do not include the smallest utilities, of 3,000 customers or less, which are not required to report usage.)
Consumers jumped the gun after the intense December storm, and then the rain stopped until mid-February, Jasperse said. “It should be a caution event to everybody - that switch turns off, and that we can’t predict that with any great level of foresight.”
Even now, the Water Agency and its municipal contractors are formulating new outdoor irrigation regulations that would restrict consumers to watering only on specific days of the week, in keeping with expanded statewide drought emergency rules adopted by the Water Resources Control Board earlier this month.