California’s dairy industry sued a state regulatory agency this week over a new order aimed at protecting Central Valley communities from nitrate pollution caused by spreading cow manure on local farmland. The suit filed Monday in Tulare County Superior Court says the order adopted last month violates state law by requiring expanding dairies to abide by the new rules as soon as they are finalized by the Central Valley Regional Water Quality Control Board, which has five years to do so. Most existing dairies, by comparison, will have 35 years to come into compliance with the rules. Board staff have said that extended timeframe was offered because the industry expressed concerns the new rules are too burdensome financially to be instituted immediately. The lawsuit against the State Water Resources Control Board follows a decade-long discussion of how to regulate dairies’ use of manure as a soil amendment.