North Bay residents appear to be holding the line on water use this summer, narrowly conserving enough to forestall the kind of water emergency that could provoke state intervention and trigger the need to cut consumption even more.
But the summer isn't over, and an unusually dry spring has put storage in Lakes Sonoma and Mendocino at their lowest levels in at least five years, according to the Sonoma County Water Agency.
"I can tell you right now that every water planner in our office is on pins and needles," waiting to see what the next month or two brings, agency spokesman Brad Sherwood said this week.
"This is serious," the agency's Assistant General Manager Pam Jeane said. "We have had an extremely dry spring, and anything anybody can do to save even a small amount of water would be extremely helpful."
Already, Lake Mendocino's water supply is down to just 43 percent of its storage capacity, or about 48,000 acre feet, according to water agency data.
The water level is so low that the U.S. Army Corps of Engineers announced Tuesday it was closing the popular lake to motorized boat travel for the foreseeable future.
Mid-summer levels haven't been this low since the 1970s, according to data from the California Department of Water Resources.
Storage at much larger Lake Sonoma is at 83 percent of capacity, but that is lower even than in 2009, when the state Water Resources Control Board directed the Sonoma County Water Agency's 600,000 domestic customers to reduce water use by 25 percent.
Residents of Sonoma and northern Marin counties have responded well to a plea from the local water agency in early June to conserve water use through a "20-gallon challenge," urging each resident to find ways to use 20 gallons less water each day.
Reduced consumption, despite heat waves in June and early July, is particularly good news given earlier high demand and polling data indicating residents had little awareness of the need to conserve this year.
Officials were pleasantly surprised, Sherwood said, when the agency's water delivery data came out last week suggesting the message had reached it audience.
But while June and July consumption was down from the same period last year, the difference in what the water agency delivered to its contractors this year from last was less than 2 percent.
So those not already watching their water use need to start now, Sherwood and others said, especially given uncertainty about how the next winter might shape up.
"We want people to know that we're on the edge," water agency Program Specialist Ann DuBay said, "and we need people to continue to conserve as they do all the time and as they've been doing this summer."
The potential shortage is a consequence of a second consecutive year of below-normal rainfall, most of which came in December before the so-called "rainy season" came to a virtual halt.
In the meantime, the Army Corps of Engineers, which manages Lakes Mendocino for flood-control purposes, made dam releases in anticipation of additional rainfall that never came.
The goal now is to balance consumer and agricultural needs along the upper reaches of the Russian River, from Ukiah to Healdsburg, in such a way that there's still enough storage in Lake Mendocino to ensure cold water releases can be made into the river when the Chinook salmon, listed as "threatened" under the Endangered Species Act, run upstream in the fall to spawn.
Maury Roos, chief hydrologist with the state Department of Water Resources, said staffers monitoring the Russian River aren't panicked yet, but they definitely have their eye on what's happening here and around the state after an unusual winter.
But he suggested the real test would come next year if the winter still to come doesn't bring substantial precipitation.
"The odds of getting sufficient rainfall in the Russian River system — the Russian/Upper Eel — are pretty good," Roos said, "but we can't be sure of it."
Jeane said the water agency and its partners in north Sonoma and Mendocino counties are promoting conservation all along the river corridor, even beyond district boundaries, where the greatest effect is likely to be felt.
North Bay residents have demonstrated over time a strong willingness to conserve water, cutting daily per capita consumption by about a quarter since 1995 and meeting targets toward the state's 2008 mandate for all Californians to reduce water use by 20 percent by 2020.
Tasked by the state in 2009 to reduce use by 25 percent, water agency consumers met that goal, too.
The current focus needs to be here and now, however, the water agency's Principal Programs Specialist Carrie Pollard said.
Each city and water district in the area offers a variety of incentives and assistance programs aimed at making conservation easy, including rebates for water-efficient appliances, payments toward conversion of lawns to less-thirsty landscapes, and free audits to help home and business owners to identify leaks or inefficiencies that can be addressed.
Rincon Valley resident Amy Southwick learned recently that her installation of a raised vegetable bed and potted plants earlier this summer just about doubled her water bill, despite steps she's taken for years to conserve, including collecting rainwater from her roof in barrels and catching water while her shower warms to use later to flush the toilet.
She said she figured out on her own, when leaves started dropping, that she was overwatering her new garden, but was stunned to find out it was enough to raise her water use so startlingly.
"There isn't enough to waste," she said.
"Every drop of water's going to really matter at the end of summer," Sherwood said, "and if you haven't started (conserving), please: Now's the time to start.
"We weren't bluffing. We weren't kidding. We were talking about low water levels in Lake Mendocino. We're seeing them now, and we need everyone to help out."
(You can reach Staff Writer Mary Callahan at 521-5249 or mary.callahan@pressdemocrat.com.)
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