HEALDSBURG, Feb. 2, 2009 ? Water suppliers for much of Mendocino and Sonoma counties as well as northern Marin County today said they plan to start implementing water-rationing measures to reduce water use by at least 30 percent and maybe by 50 percent as projections suggest there won't be enough water for residents, businesses and migrating protected fish by the fall at current reservoir levels and rates of consumption.
The Sonoma County Water Agency, which supplies 750,000 people in Sonoma and northern Marin counties, has told the municipalities and water districts it supplies to plan for 30 percent reductions in the amount of water the agency supplies, according to Paul Kelley, a member of the county board of supervisors and an agency director.
"If things don't change we will have 30 percent rationing this year and at worst 50 percent," he said at a news conference held at Healdsburg Memorial Beach along the Russian River.
The water flow from Lake Mendocino was halved to 75 cubic feet per second under "dry year" measures allowed in waterways with protected fish, according to the water agency. Flows in the lower Russian River were trimmed to 85 cubic feet per second. Cuts for Dry Creek flows from the Lake Sonoma reservoir won't change until April at the earliest.
The Mendocino County Russian River Flood Control and Water Conservation Improvement District could move to restrict supply to its customers if the level of Lake Mendocino persists, according to General Manager Sean White.
Mendocino County's action would affect 1,000 acres of winegrapes and as many acres of pears. In Sonoma and Mendocino counties, about 60,000 acres of winegrapes are supplied with water for irrigation and/or frost protection from the Russian River and its tributaries.
Duff Bevill, a grapegrower and director of the Sonoma County Winegrape Commission, said the group will start disseminating in coming days best management practices for dramatically reducing water use.
"Drought is nothing new to us," he said.
One of those practices is the mowing or spraying of cover crops commonly planted among the vines to prevent erosion and bring nutrients to the soil, according to Pete Opatz of Silverado Premium Properties. Those crops also absorb soil moisture for three months of the year, and removing them ? except along waterways to protect water quality ? can reduce water use by 18 percent to 20 percent.
Another practice the winegrape commission is considering is grape cluster removal along with the vine shoot to which the clusters are connected, as has been done in northern Spain for a century, according to Mr. Opatz.