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Aquatic Scientists Criticize Revised Definition of Waters of the U.S.

Thursday, January 23, 2020

January 23, 2020
(301) 897-8616 x202


(Bethesda, Md.) January 23, 2020 — The U.S. EPA and the Army Corps of Engineers have redefined the extent of protection for the nation’s freshwater resources. The Consortium of Aquatic Science Societies, a group of nine professional societies with a total of more than 20,000 member scientists, strongly criticized the new definition of the “Waters of the United States (WOTUS).” The redefinition is inconsistent with the best-available science. It removes protection for millions of stream miles and acres of wetlands that keep waters and watersheds healthy.  

The Clean Water Act’s mandate is “to restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” The new rule eliminates protection for waters that otherwise maintain watershed integrity, thus rendering the objectives of the Clean Water Act unattainable.  

Impairment of headwaters and wetlands affects water quality and flow for entire watersheds. The rule threatens critical headwater and wetland ecosystem services, like water quality protection, aquifer recharge, organic material transport, safeguarding habitats for endangered species, and support for recreational and commercial fishing economies. Climate change and land use intensification have already shifted waters that were permanent to intermittent and intermittent to ephemeral. Under the revised WOTUS, more waters will lose protection, thus severely undermining our nation’s water quality and fisheries. 

A recent report from the American Fisheries Society found that headwater ecosystem impairment, loss, or destruction is assured under the revised WOTUS rule, and would have severe and long‐lasting negative consequences for fisheries and environmental conditions throughout the USA.  Headwaters act as a conveyor of nutrients, a path for migrating fish and wildlife, and a drainage and storage system for floodwaters. “The published science demonstrates that the loss of protections for our nation’s most vulnerable waters will have far-reaching implications for fish, wildlife, and their habitats,” said American Fisheries Society Executive Director Doug Austen, Ph.D.  

"We have a clear understanding of the critical functions provided by our wetlands, including maintenance of clean water.  We should be seeking ways to preserve and strengthen these benefits. Instead, the proposed new rule, which flies in the face of good science, will weaken protection for headwater streams and associated wetlands, systems that are key to safeguarding healthy watersheds,”  said Loretta Battaglia, Ph.D., President-Elect of the Society of Wetland Scientists.

Our nation's estuaries and coastal waters are vital to our economic prosperity and sustainability. The health of these waters is influenced not just by the flow of streams and rivers, but also through groundwater connections to wetlands, dammed and diked areas, and ditches in coastal watersheds. “The proposed new rule will weaken protection of the water quality and biological integrity for these vital ecosystems,” said James Fourqurean, Ph.D., President of The Coastal and Estuarine Research Federation.

Perry Thomas, Ph.D., President of the North American Lake Management Society, said, "Even our highest quality lakes are threatened by erosion and other degradation in their watersheds. If we are going to protect these incredibly valuable water bodies we need to manage stormwater and address erosion in these lake watersheds but that would be essentially lost under the proposed WOTUS definition that excludes many headwater streams and wetlands."

“The science on the connectivity between headwater streams, wetlands, and ecosystem services like clean water is undisputed,” asserts Amy Rosemond, Ph.D., President of the Society for Freshwater Science, “however, the EPA has chosen to ignore this science. This includes ignoring the conclusions of EPA’s own staff scientists and science advisory board. The new rule is simply not scientifically defensible and the decision to ignore the science was arbitrary and capricious.  The logical outcome of today’s rule will be a degradation in water quality and increasing threats to human health.”

For more information on the Waters of the United States, see

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