Latest Science Informs Final Clean Water Rule

By Ken Kopocis

At EPA, we utilize the latest and best available science to inform our decisions. This extends to our rule to protect clean water that we are developing jointly with the U.S. Army Corps of Engineers. We aim to release it in spring 2015.

This week our Office of Research and Development released its final assessment of the science on how streams and wetlands are connected and affect downstream waterways. Referred to as the connectivity report, it is a review of more than 1,200 pieces of independent, peer-reviewed, and published scientific literature.

In short, this research shows us how streams and wetlands impact the rivers, lakes, bays, and coastal waters they flow into. About 60 percent of stream miles in the U.S. only flow seasonally or after rain, but they have a considerable impact on downstream waters. And approximately 117 million people – one in three Americans – get their drinking water from public systems that rely on these streams. Streams and wetlands provide many benefits to communities – they trap floodwaters, recharge ground water supplies, remove pollution, and provide habitat for fish and wildlife. They’re also economic drivers because they support fishing, hunting, agriculture, recreation, energy, and manufacturing. Science shows that these streams and wetlands are vital to our health and the environment, so we are committed to protecting them as we develop our final Clean Water Rule.

EPA and the Army Corps of Engineers wouldn’t finalize the Clean Water Rule until the final science report was available, but have factored in science findings throughout the process of drafting the Clean Water Rule, including:

  • Release of the draft connectivity report in 2013.
  • Input from EPA’s Scientific Advisory Board at public meetings in 2013 and 2014 and in written comments submitted by the SAB in October 2014.
  • Regular updates on changes to the connectivity report from our Office of Research and Development during fall 2014.

As our agencies work to finalize the Clean Water Rule, we are considering all scientific research we’ve reviewed in addition to the nearly 900,000 public comments that were submitted. We have listened carefully to the feedback from everyone on the draft proposal during the seven months it was open for comment. We greatly appreciate the valuable input and thoughtful suggestions, and will be making changes to the final rule as part of our commitment to getting it right. Our goal is to find a balance that reflects the best science, is reasonable for all parties, and protects the clean water we depend on.

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