The Clean Water Act (CWA) significantly improved surface water quality, but at a cost exceeding the estimated benefits. We quantify the effect of the CWA on a direct measure of health and incorporate health benefits into a cost-benefit analysis. Using a difference-in-differences framework, we...

In the half century since the founding of the U.S. Environmental Protection Agency, public and private U.S. sources have spent nearly $5 trillion ($2017) to provide clean rivers, lakes, and drinking water, or annual spending of 0.8 percent of U.S. GDP in most years. Yet over half of rivers and...