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 substantial shares of drinking water systems violate standards, and polls for decades have listed water pollution as Americans’ number one environmental concern. We assess the history, effectiveness, and efficiency of the Clean Water Act and Safe Drinking Water Act, and obtain four main conclusions. First, water pollution has fallen since these laws, in part due to their interventions. Second, investments made under these laws could be more cost-effective. Third, most recent studies estimate benefits of cleaning up pollution in rivers and lakes which are less than their costs, though these studies may under-count several potentially important types of benefits. Analysis finds more positive net benefits of drinking water quality investments. Fourth, economic research and teaching on water pollution is relatively uncommon, as measured by samples of publications, conference presentations, and textbooks.

中文翻译：

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美国过去半个世纪的水污染法规：将水烧成水晶泉？

自美国环境保护局成立以来的半个世纪中，美国的公共和私人来源已花费近5万亿美元（2017年）来提供清洁的河流，湖泊和饮用水，或者在大多数年份中每年花费占美国GDP的0.8％ 。然而，超过一半的河流和大量饮用水系统违反了标准，数十年来的民意测验已将水污染列为美国人关注的第一大环境问题。我们评估了《清洁水法》和《安全饮用水法》的历史，有效性和效率，并得出了四个主要结论。首先，自这些法律以来，水污染有所下降，部分是由于它们的干预。其次，根据这些法律进行的投资可能更具成本效益。第三，最新的研究估计，清理河流和湖泊污染的收益低于成本，尽管这些研究可能没有充分考虑到几种潜在的重要收益。分析发现，饮用水质量投资具有更多积极的净收益。第四，以出版物，会议报告和教科书的样本衡量，关于水污染的经济研究和教学相对较少。