NORTH COAST – Three environmentalist groups say they will sue state and federal regulators next month if they don't take action on use of Russian River Basin waterways for agricultural frost protection and irrigation, activities the groups claim is harming threatened and endangered fish.Loss of water for frost protection would deal a serious blow to crop protection during the early part of season, when vine growth is vulnerable. Mendocino County farm groups say coating the sensitive parts with protective ice at the coldest part of the night is more effective than wind machines because of climate and terrain.Tucson, Ariz.-based Center for Biological Diversity, Sebastopol-based Northern California River Watch and Point Arena-based Coast Action Group sent a letter to the State Water Resources Control Board and the U.S. Commerce Department, which oversees the National Marine Fisheries Service, informing them they intend to file suit against them in federal court after mid-January."Permitted and unpermitted use of water to protect grape crops from frost has been determined, through legal proceedings, to be an unreasonable, wasteful and excessive use of water," wrote the Santa Rosa attorney for the groups, Jack Silver, in the 15-page letter dated Nov. 17, a day before a water board workshop on water use for frost. The federal Endangered Species Act requires a 60-day notice of intent to sue so that alleged problems can be addressed.The groups want the fisheries service to take criminal action.They also want the water board to restrict new water permits for pumping from creeks and adjacent wells as well as storage in reservoirs. The water board is expected to consider rules on such water use at a meeting being arranged for Jan. 5.A number of agriculture groups have been scrambling to prepare fish-protection plans in the past several months, drawing on existing programs such as Napa-based Fish Friendly Farming certification. The intent-to-sue letter has pushed some of the efforts into high gear, according to Carolyn Wasem, who has helped draft best-management practices for the wine business and property owners in frost-protection and fisheries."We're really making some efforts to get this done to address the needs of the fisheries but that protects the needs of the industry," she said. "Right now, there is a threat of a lawsuit looming over the industry."A number of presentations are planned for the first half of January to acquaint growers and property owners to the risk posed by strict new rules on agricultural water use, particularly for frost protection, and encourage collection of water-use data, according to Nick Frey, president of the Sonoma County Winegrape Commission. * Mark West Creek watershed: Jan. 6, 4 p.m., Kendall Jackson Wine Center, 5007 Fulton Rd., Fulton* Green Valley: Jan. 7, 4 p.m., Dutton Pavilion at Santa Rosa Junior College Shone Farm, 7450 Steve Olson Lane Forestville* Knights Valley: Jan. 8, 10 a.m., Knights Valley Fire Department, 16850 Spencer Lane, Calistoga * Dry Creek and Alexander valleys: Jan. 8, 4 p.m., Healdsburg Community Center at Foss Creek Elementary School, 1557 Healdsburg Ave., Healdsburg* Russian River Basin: Jan. 14, 10 a.m., Dutton PavilionInformation on crop insurance as a risk-mitigation measure at the commission's Jan. 21 Dollars & Sense grape market economics seminar in Santa Rosa.This hint of legal action is part of decades of debate, court rulings, regulations and legislation over use of water from North Coast waterways that could hurt survival of listed species, namely coho and chinook salmon and steelhead trout. Mr. Silver cited a 1972 court decision controlling Napa River Basin water use for vineyard frost protection. He also pointed out that 70 percent of the 60,640 acres of vineyards in the Russian River Basin are within 300 feet of the 1,778 miles of river and tributaries listed as fish habitat.What brought the frost issue to a head was an early 2009 letter from the National Marine Fisheries Service enforcement office in Santa Rosa pointing to three incidents of fish death in the main stem of the Russian River in Mendocino County and in the Felta Creek tributary in Sonoma County. Amid the worst stint of frosty spring nights in three decades, growers drained reservoirs that typically are sized to handle the normal pattern of no more than a few annual nights of frost and not many back to back.The fisheries service called on the water board to restrict use of water for frost protection.Another reported stranding of juvenile listed fish was reported this spring on Felta Creek.In the intent-to-sue letter, the groups allege the water board has been violating the species law by authorizing diversions of water to pumps and private reservoirs in the Russian River and Gualala watersheds said to be already over-allocated for vineyard uses in a 1997 board staff report.Farm and wine groups in Mendocino County formed the Upper Russian Stewardship Alliance, and like groups in Sonoma County formed the Middle Russian Stewardship Alliance. A group in Sonoma County led by the Russian River Property Owners Association also has developed a habitat-protection plan.The alliances presented a collective basin protection plan at a second frost workshop held by the water board last month. It was a followup to a stern warning the water board gave North Coast growers in April about future use of water for frost protection.At the November workshop federal and state wildlife regulators told the water board the proposed mitigation plans didn't go far enough in monitoring water use and identifying which property is using how much and when. Property owners and farming groups plan to meet with regulators this week to see what adjustments can be made."It will be interesting to see if the resources agencies and the parties intending to sue think it goes far enough," Ms. Wasem said.