North Coast water woes reflected in dwindling reservoirs (w/video)

California turned the page this week on the fourth-driest water year on record, an occasion marked on the North Coast by dwindling reservoir supplies and restrictions on water use.

Without normal or near-normal rainfall in coming months, water managers warn that the situation could get much worse, resulting in stricter rationing and tighter limits on water supplies for agricultural users.

'It's safe to assume that we are preparing for the worst-case scenario, which would be another dry winter,' said Brad Sherwood, a spokesman for the Sonoma County Water Agency.

In Healdsburg, city leaders already are debating whether to begin issuing citations for the heaviest water users, according to Mayor Jim Wood, who expressed dismay at the number of green lawns he said he sees when he drives around town.

'I hate to do it. I don't want to do it. But people have to understand this is a big deal,' Wood said of possible fines.

The North Coast has managed to avoid the more severe water restrictions implemented in areas of the state hit hardest by the drought. But that could change if this winter brings another paltry dose of precipitation. This weekend's forecast calling for scorching heat doesn't help matters.

Lake Mendocino is only 27 percent full, or nearly three-quarters empty. The lake on Wednesday was at the third-lowest level for that date since 1958. As a result, upper Russian River communities have implemented mandatory conservation orders and in-stream flow requirements have been cut to 50 cubic feet per second, compared with 75 cfs earlier this year, according to Sherwood.

'It's just really looking terrible out there right now,' said Sean White, general manager of the Russian River Flood Control District.

Lake Mendocino held 30,074 acre-feet of water Wednesday, about half of the historical average for storage at this time of year. Still, that level was well above the record low of 13,200 acre-feet in 1977, which generally is thought of as the worst drought year on the North Coast to date.

Lake Sonoma was faring better Wednesday, at 60 percent of capacity. But that level was the fifth-lowest for that date since 1983. The region's largest reservoir, Lake Sonoma holds 245,000 acre-feet of water. This week it was at 147,673 acre-feet, and if it reaches 100,000 acre-feet, mandatory 30 percent cuts for Water Agency contractors kick in, Sherwood said.

Lake Sonoma, which opened in 1982, provides water to 600,000 people in Sonoma and Marin counties.

Many North Coast residents already have cut their water use way back to help with conservation efforts. Sherwood said per-capita water use for the month of August for the Water Agency and its customers was down 41 percent compared with a 10-year baseline for that month, excluding drought years.

Another year of drought conditions could spur additional water reductions.

At least seven Sonoma County cities, along with the Valley of the Moon Water District, have required residents to cut use by 20 percent. They include the cities of Healdsburg, Windsor, Santa Rosa, Sebastopol, Rohnert Park, Cotati and Sonoma.

In Mendocino County, the city of Ukiah enacted mandatory water restrictions that, among other things, limit residential irrigation to no more than every other day. Willits asks residents to voluntarily reduce their water usage by 20 percent. The Redwood Valley County Water District north of Ukiah limits residents to 50 gallons of water per day.

Wood said the Healdsburg City Council at its last meeting directed staff to compile a list of the city's most egregious water wasters in advance of possibly levying fines against them. He said people who've already reduced consumption by the requested 20 percent would be spared further measures.

'We're asking their neighbors to do more and to step up to the plate,' he said.

At Yorty Creek at Lake Sonoma, the water has receded past the boat launch area, Tuesday Sept. 30, forcing people to drive the river bed to use the lake. (Kent Porter / Press Democrat) 2014

Calculating how much rain the North Coast will need in coming months to reverse drought conditions is tricky given the region's diverse geography and the varying reliance on the Russian River, reservoirs and private wells to service water needs.

But in general, a normal amount of annual rainfall for the Santa Rosa basin is about 32 inches. The area received a scant 18 inches of rain between July 2013 and July 2014, the annual breakdown provided by the Water Agency.

During the same period, the Ukiah Valley basin received only 16 inches of rain, about 43 percent of its normal amount.

While 2013 was the driest calendar year on record for California, the state calculates a water year from October to September, meaning that on Wednesday, California officially entered its fourth year of drought.

Going forward, the timing of any rain matters, in particular for Lake Mendocino, which the U.S. Army Corps of Engineers manages for flood control purposes. Local water managers are hoping to avoid a repeat of previous years when water was released from the lake during winter storms, ostensibly to protect Coyote Dam.

Sherwood said the Water Agency, which controls water in the lake below the flood pool, has partnered with the Scripps Institution of Oceanography and the Center for Western Weather and Water Extremes to advance research in ocean science and meteorology.

Researchers are hoping to determine the role that large, moisture-laden winter storms, known as atmospheric rivers, play in filling Lake Mendocino so that they can improve rain forecasts and retain more water in the reservoir without increasing flood risk.

White, with the Russian River Flood Control District, suggested the formula the feds currently use for managing flood control at the lake is outdated. He said other restrictions also limit when water can be stored in the lake.

'It doesn't really matter how much water we get in winter,' he said. 'What really matters is how much water we get in late spring. That's the only time we are allowed to store it under the current regime.'

You can reach Staff Writer Derek Moore at 521-5336 or derek.moore@pressdemocrat.com. On Twitter @deadlinederek.