UKIAH — Scores of Sonoma and Mendocino county grape growers and other farmers packed a Mendocino County Superior Court room Thursday for a lawsuit challenging state frost protection rules for stretches of the Russian River watershed.
Regulators say the rules are necessary to protect salmon and steelhead, the latter a threatened species. Farmers and their attorneys say the regulations are unneeded, trample farmers' water rights and exceed the state Water Resources Control Board's authority.
Mendocino County Superior Court Judge Ann Moorman took the matter under submission after hearing the attorneys argue their cases. She has 90 days to make a ruling.
At issue is the amount and timing of diversions of water from the river and key tributaries during the springtime for use in spraying to protect vulnerable grapes and other crops from frost damage.
The state regulations require significant data collection. They include requiring farmers to install stream flow guages and to measure and report how much water is diverted for frost protection. A stream monitoring program must be developed in consultation with federal and state fish authorities.
It also requires that farmers assess the liklihood their stream diversions could cause fish to become stranded.
The rules were adopted last year by the state Water Resources Control Board but were suspended in February pending the lawsuit's outcome.
The goal is to prevent sudden drops in water levels that sometimes occur when growers simultaneously suck water from the river to spray crops during frosty nights.
The practice can cause the deaths of young salmon that can become stranded by abrupt water level declines, according to the state and environmentalists.
The lawsuit focuses on two such incidents along the Russian River and its tributaries in 2008 — one in Sonoma County and one in Mendocino County. The link of one of the two incidents to frost protection is questionable, Judge Moorman noted.