V. Kerry Smith and Carlos Valcarcel Wolloh, economists at Arizona State University, take a look at the effects of the Clean Water Act, enacted 40 years ago in 1972 by President Nixon: "we find average water quality in U.S. lakes is at about the same level in 2011 as it was in 1975." Also, a bad economy is good for water, and vice versa: "As the unemployment rate rises, all the national indexes for water quality improve and the reverse seems to accompany improving economic conditions." They say that calls into question the popular idea that as household income increases so does environmental quality.
The title of their working paper from the National Bureau of Economic Research is "Has Surface Water Quality Improved Since the Clean Water Act?"
