Clean Water Act Dramatically Cut Pollution in U.S. Waterways

October 09, 2018

The 1972 Clean Water Act has driven significant improvements in U.S. water quality, according to the first comprehensive study of water pollution over the past several decades, by researchers at UC Berkeley and Iowa State University. Despite clear improvements in water quality, almost all of 20 recent economic analyses estimate that the costs of the Clean Water Act consistently outweigh the benefits, the team found in work also coauthored with researchers from Cornell University. These numbers are at odds with other environmental regulations like the Clean Air Act, which show much higher benefits compared to costs. “Water pollution has declined dramatically, and the Clean Water Act contributed substantially to these declines,” said ARE Associate Professor Joseph Shapiro. “So we were shocked to find that the measured benefit numbers were so low compared to the costs.”