The North Coast needs an additional foot of rain between now and May just to get back to drought conditions seen in 1977, and even then Lake Mendocino could still go bone dry by autumn for the first time in recorded history, water officials said Tuesday.
The warning stunned North Coast grape growers who packed a Cloverdale meeting hall Tuesday to discuss ways of saving their crops amid the worst drought any of them can recall.
None of the strategies, which ranged from installing more wind machines to covering ponds with plastic tarps to reduce evaporation, compared with what everyone agreed is the most pressing need: more rain and lots of it.
If Lake Mendocino runs dry, it could be disaster for growers, in particular those with vineyards along the upper Russian River. Many rely on water from Lake Mendocino for irrigation, as well as for frost protection.
"If you're below Dry Creek, it's going to be a bad year. If you're above Dry Creek, it's going to be a biblical year," said Sean White, general manager of the Russian River Flood Control District.
Dry Creek is a Russian River tributary that carries outflow from Lake Sonoma, the principal water source for much of Sonoma County. Dry Creek joins the Russian River southwest of Healdsburg.
White's assessment silenced the crowd of more than 150 growers, vineyard managers, scientists and government officials who gathered Tuesday at the Cloverdale Citrus Fairgrounds for the meeting, which was sponsored by the Mendocino County Farm Bureau and Sonoma County Winegrowers.
Grape growers have been on notice for weeks that their livelihoods are at risk this year because of the dry weather, which has accelerated bud activity across the region and heightened fears of frost damage. As a result, many growers have purchased crop insurance.
"I think everybody's got a good sense of the reality," said Bob Anderson, executive director of United Winegrowers for Sonoma County.
Lake Mendocino was at 36 percent of capacity Monday with 24,621 acre-feet of water, said Pam Jeane, assistant general manager of the Sonoma County Water Agency.
Jeane said the upper Russian River Valley watershed will need a foot of rain over the next three months -#8212; combined with a 45 percent reduction in demand -#8212; to return to levels recorded during the 1977 drought. The rainfall totals for the watershed are similar to what the entire region would need to return to 1977 levels.
White said outflow from the lake into the upper Russian River has been reduced to 30 cubic feet per second to conserve as much as possible amid drought conditions. He said the flow would need to be around triple that amount in order for officials to feel comfortable about the water being used for frost protection.
Devon Jones with the Mendocino County Farm Bureau said growers who divert water directly from the Russian River are "going to really have to think twice before you turn the pump on this year."
In 2011, state regulators took aim at the practice through new rules that would have limited use of Russian River water for frost protection.
Federal officials say such diversions are a primary cause of mass strandings for federally protected salmon and steelhead runs in the river. But growers, who contest those claims, challenged the rules in court. The case is currently on appeal.
The looming frost season could prove a key test of growers' voluntary measures, including the switch to stored water for frost protection.
Jones, the Farm Bureau official, said she's already fielded calls from people sharing concerns that agriculture is responsible for declines in the river's flow, which can be tracked online.
Jones said she told the callers such dips can result from a number of factors, including scientists recalibrating monitors.
"I don't want the finger-pointing this early in the season," she said.
Jones warned meeting participants Tuesday to be aware that the public is closely watching their water use, saying growers "don't need more accusations about strandings."
David Reynolds, a senior meteorologist with the University of Colorado, provided a bright moment Tuesday with his prediction that up to three inches of rain could fall in Sonoma County this weekend, along with up to five inches in Mendocino County.
"Bring it on!" a man in the audience yelled, prompting cheers.
"Remember, it's a forecast," Reynolds said.
"Oh, he's dodging the bullet!" someone else yelled.
Even with the rain, grape growers expect a smaller crop this year. The only question is the extent of the loss.
Water conservation strategies discussed Tuesday included the use of probes to monitor below-surface soil conditions for optimal irrigation.
"Don't irrigate below the active root zone. We want to be stingy with our water," said Mark Greenspan with Advanced Viticulture, Inc.
Speakers said growers could benefit from technologies that provide weather conditions in real-time down to a single vineyard, or those that monitor inversion layers, which can help combat frost when used in conjunction with heaters and wind machines.
Al White with Mendocino Wine Company and Husch Vineyards said one strategy he's planning to employ is to cover a pond with polymer to reduce evaporation. His suggestion to do the same at Lake Mendocino drew chuckles.
Doug McIlroy, director of winegrowing at Rodney Strong Wine Estates, said growers may have to resort to spraying copper sulfate on grapes for added frost protection.
McIlroy reported that the 30 cubic feet of water flowing per second on the Russian River near Cloverdale this week compares with 4,500 cubic feet for the same period in 2008.
In normal water years, Rodney Strong can employ a well capable of pumping 3,000 gallons per minute to battle frost on a 70-acre vineyard in Alexander Valley, McIlroy said.
"Do you think we'll turn that on with those kinds of flows (from the Russian River)? Most likely not," he said.
White told growers that if drought conditions persist they may have to start looking beyond 2014. "I think you guys are going to have to really take a sobering look at what you want your long-term look to be," he said.
In response to demand, Sonoma County Winegrowers is hosting another meeting about drought-related issues Feb. 21 at the Sonoma County Fairgrounds in Santa Rosa for growers, as well as for ranchers and dairy farmers. More information can be found at www.sonomawinegrape.org.
You can reach Staff Writer Derek Moore at 521-5336 or derek.moore@pressdemocrat.com. On Twitter @deadlinederek.
UPDATED: Please read and follow our commenting policy: