EPA Leadership Ignored EPA Scientists’ Concerns Over Mississippi Wetlands

Published Jun 29, 2022

What Happened: While drafting an environmental impact statement, political appointees at the Environmental Protection Agency (EPA) failed to incorporate the science-based concerns of EPA scientists. The EPA scientists provided scientific input on how implementing a massive Mississippi flood control project, the Yazoo Pumps project, would drain and damage thousands of acres of ecologically rich wetlands, an action which could have constituted a violation of the Clean Water Act.

Why it Matters: Science is required by law to inform the evaluations of environmental impact of proposed projects. EPA officials politicized one of the major ways that we use science to protect the environment by failing to incorporate the best available science from career scientists. Political interference from EPA leadership under Trump resulted in EPA career scientists having their comments and concerns omitted out of public comment periods. The EPA scientists stated that the project could have devastating effects on the aquatic life, wildlife, and communities that depend on and live near these wetlands along the Mississippi Delta.

Environmental Protection Agency (EPA) leadership under the Trump administration failed to incorporate evidence-based comments and concerns from EPA scientists on the ecological impact of a massive Mississippi flood control project. The Yazoo Pump project was previously vetoed by the Bush administration in 2008 due to scientific evidence showing there would be significant degradation of thousands of acres of ecologically rich wetlands because of Yazoo pump construction, the last part of the flood control project.

Following the Great Flood of 1927, Congress acted and passed the Flood Control Act the following year, which was later updated and expanded upon by Congress in 1936 and 1941. In 1941, Congress authorized the Yazoo Backwater Project – a combination of levees, drainage structures, and pumps – to help prevent frequent flooding events along the Mississippi Delta.

The US Army Corps of Engineers drafted a supplement to the final environmental impact statement issued in 2007, which was later vetoed by the Bush administration due to science-based concerns on the project’s ecological impact. In April 2020, US Army Corps of Engineers announced their intent to draft a second supplement. EPA scientists attempted to voice their science-based concerns in a public comment over the revival of this project and the adverse impact it would have on wetlands and surrounding communities. However, when the scientists’ public comment letter was reviewed by EPA senior officials, the officials edited out these science-based concerns. The scientists were not informed of these major changes to the public comment letter.

“The final version of EPA’s 2020 DSEIS [draft supplemental environmental impact statement] comment letter, which was not vetted by EPA career scientists prior to issuance, included changes made by or directed by EPA senior leadership that resulted in significant inaccuracies and omissions” stated Palmer Hough, a scientist in the EPA’s Office of Wetlands, Oceans and Watersheds, and William Ainslie, a wetland scientist in the Region 4 office in Atlanta. They also noted that EPA scientists were “deeply disturbed” by these unauthorized changes to their comment letter. EPA career scientists did not see any of their concerns addressed in the final supplement to the environmental impact statement and responded to this political interference via public comment, which was submitted on January 6, 2021. However, EPA leadership once again interfered and did not submit the scientists’ public comment by its deadline of January 11.

EPA scientists extensively detailed in a January 2021 memo their concerns with the Yazoo Pumps project, including the degradation of 194 acres of wetland due to pump construction and secondary adverse impacts on approximately 69,000 acres of wetlands. According to the EPA scientists, “impacts [from the building of the Yazoo pumps] will degrade the ability of affected wetlands to perform important ecological functions,” which the scientists state could constitute a violation of the Clean Water Act. Upon review of the US Army Corps of Engineers’ biological assessment, the US Fish and Wildlife Services determined it provided “an insufficient analysis of the project and its effects.”

Based on the best available science that suggested devastating impacts on thousands of acres of wetlands, EPA scientists advocated for the termination of the Yazoo Pumps project. As stated by the EPA website, "Wetlands are among the most productive ecosystems in the world” and they “provide values that no other ecosystem can.” By editing out the evidence-based concerns of EPA scientists, EPA officials prevented the best available science from informing the decision-making process, which in turn jeopardized fragile wetland ecosystems and the livelihoods of communities along the Mississippi Delta most at-risk of flooding.