Environmental Groups Sue Corps Over Mississippi River Management Plan

Five conservation groups have sued the Corps of Engineers, blaming the use of river training structures like wing dikes and bendway weirs for what they claim is an increased risk of flooding along a 195-mile stretch of the Middle Mississippi River between St. Louis, Mo., and Cairo, Ill. The lawsuit was brought by the National Wildlife Federation, American Rivers, Prairie Rivers Network, Missouri Coalition for the Environment and Great Rivers Habitat Alliance.

The lawsuit, filed in the U.S. District Court for the Southern District of Illinois, challenges the Corps’ Supplemental Environmental Impact Statement for the Regulating Works Project. The Regulating Works Project guides the Corps’ management of this section of the Mississippi River.

“The Army Corps has opted to continue to recklessly follow a century-old plan that increases the risk of catastrophic floods while destroying vital wildlife habitat,” said Melissa Samet, Senior Water Resources Counsel at the National Wildlife Federation. “It is unfortunate that we had to go to court to urge the agency to assess all the risks and evaluate modern approaches. However, last year’s flooding shows how critical it is that the Army Corps get this right.”

“Great Rivers Habitat Alliance is a part of this important lawsuit because we feel it is imperative that all government agencies properly consider the cumulative impacts of their individual project proposals, which far too many government entities at every level fail to do,” said David Stokes, the executive director of the Great Rivers Habitat Alliance. “We also support limits on structural projects to attempt to manage our great rivers.”

The Corps has built training structures that alter the river’s flow along hundreds of miles of river.  They are used by the Corps to direct water and sediment flow for various purposes. They can be used to scour out navigation channels and reduce the necessity of dredging to maintain them, or to create wildlife protection areas away from the channel.

The groups allege that these structures—which include wing dikes, bendway weirs and chevrons—have increased flood height by up to 15 feet in some locations and 6 to 8 feet in broad stretches of the Middle Mississippi. In a press release, the groups said, “The impacts of these and other Army Corps actions on the river have so constricted the river that it now suffers from the type of flash flooding more typical of a much smaller river.”

Most Endangered River

“American Rivers named the Upper Mississippi as America’s Most Endangered River for 2020 because of the urgent threat of flooding and climate change. The Army Corps’ outdated approaches threaten community safety and river health. It is critical that the Corps reevaluate the impacts of its plan and consider more effective solutions. It is time to change course,» said Olivia Dorothy, Upper Mississippi Basin Director for American Rivers.

The lawsuit seeks to require the Corps to redo its environmental review, stop or limit construction of new river training structures and “effectively mitigate” the impacts of its Regulating Works Project. The groups are represented by the Law Offices of Stephan C. Volker and St. Louis-based Great Rivers Environmental Law Center.

The Corps’ Mississippi Valley Division declined to comment on the suit.