The U.S. EPA is required by the Clean Water Act to protect the nation’s waterways and drinking water from construction-industry pollution, and the agency must develop regulations to address construction-site runoff by December 2009, a federal appeals court ruled [PDF] Thursday. Sediment from construction sites, usually washed into rivers and other waterways via storm water, can contain pollutants like heavy metals, and often spurs excessive algae growth. The EPA started to develop regulations for construction-site runoff in 1999, declaring then that it “can contribute high loadings of nutrients and metals to receiving streams” and that state and local regulations were not doing enough. However, the EPA suddenly reversed course in 2004 and withdrew its proposal, saying such regulations were unnecessary. The Natural Resources Defense Council and other groups soon sued to force the agency to follow through, and both a lower court and now a federal appeals court agreed, ruling that EPA actually does have to develop such regulations. “For too long EPA has turned away from the real work of protecting our waters. This decision forcefully reminds them of their duty,” said Jeffrey Odefey of the Waterkeeper Alliance.