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Section 404 of the Clean Water Act

Draft Scientific Report Connectivity of Streams and Wetlands to Downstream Waters: A Review and Synthesis of the Scientific Evidence

This draft report from EPA's Office of Research and Development synthesizes the peer-reviewed scientific literature pertaining to biological, chemical, and hydrologic connectivity of waters and the effects that small streams, wetlands, and open waters have on larger downstream waters such as rivers, lakes, estuaries, and oceans. The draft report was out for public review and comment through November 6, 2013 as part of a Science Advisory Board-led peer review.

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