The proposed change to the definition of “waters of the United States” flouts sound science

Abstract

The U.S. Environmental Protection Agency (EPA) and Army Corps of Engineers (hereafter, “the agencies”) have issued a proposed rule (1) that would remove Clean Water Act (CWA) protections from more than half of wetlands and one-fifth of streams in the United States (2). This move sharply contrasts with reports indicating that US waters remain threatened by storms, droughts, contaminants, algal blooms, and other stressors. Even the EPA’s National Water Quality Inventory detected poor conditions in 46% of stream and river miles and 32% of wetlands (3). In short, the proposed rule does not reflect the best-available science and, if enacted, will damage our nation’s water resources. A proposed rule under consideration by the US federal government does not reflect the best-available science and, if enacted, will damage the nation’s water resources. Image credit: Shutterstock/Martha Marks. Despite the CWA’s mandate “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters” (4), controversy persists over jurisdiction. For decades, the protected “waters of the United States” (WOTUS) included traditionally navigable waters (TNWs), such as large rivers, lakes, and territorial seas, as well as waters meaningfully connected to or affecting the integrity of TNWs. Operationalizing this connection has become a flashpoint for the science and politics of water protection. Connectivity among waterbodies was the cornerstone of the Obama administration’s Clean Water Rule (CWR), which reflected a state-of-the-science synthesis of more than 1,200 scientific publications [known as the “Connectivity Report” (5)], input from 49 experts, and a rigorous review by a 25-member panel of the EPA’s Scientific Advisory Board (SAB) (6). Since then, scientific evidence supporting the 2015 CWR, and hence contradicting the new proposal, has only accumulated, especially as related intermittent (i.e., flow seasonally) and ephemeral (i.e., flow periodically, after precipitation events) streams, riparian and floodplain zones, and non-floodplain wetlands … [↵][1]1To whom correspondence may be addressed. Email: sullivan.191{at}osu.edu. [1]: #xref-corresp-1-1