The U.S. Army Corps of Engineers is proposing a new Mississippi River restoration project, starting with a 39-mile stretch near Memphis, Tennessee, that could help save threatened and endangered aquatic animals. The agency still needs to secure $50 million in funding.
The plan results from a major Corps study recently completed in the lower Mississippi River. Officials hope it will be a model for future, similar projects.
The lower Mississippi River’s levee system has disconnected much of its main channel from its historic floodplain — an unintended consequence of Army Corps flood control and navigation projects, which have transformed the behemoth river to a more managed flow.
The Mississippi River has historically topped its banks and changed course as it sought the path of least resistance to the Gulf of Mexico, but levees have held the river back and changed the natural flow. That has diminished the connections between the river and the floodplain, while reducing habitat diversity and increasing the presence of invasive species, the Corps said in a report on the proposed restoration project.
Less than 25 percent of the lower Mississippi River Valley’s original forested wetlands remain.
“Although the levee system has reduced the footprint of the historic plain, its ecological value reflects a complex mosaic of diverse aquatic and vegetative habitat,” the Corps said in the report.
‘Flagship study’ near Memphis
The seed for the project was planted more than two decades ago with the passage of the Water Resources Development Act of 2000, a biennial legislative package that authorizes the Corps’ activities.
A follow-up assessment in 2015 identified eight segments of the river to focus on, including near Memphis.
When the study of the Memphis area — the largest of its kind on the lower river — ended last year, the Corps used its findings to propose the new restoration project for a 39-mile stretch of river that will benefit more than 6,000 acres, from the Lower Hatchie National Wildlife Refuge to the mouth of the Wolf River near, downtown Memphis.
“This is really a significant study because of the size,” said Jason Allmon, project manager at the Corps’ Memphis District.
The project has a few aims: increase vegetative habitats, optimize connections between the river and the floodplain, and give the public more access for recreation.
The initial construction and engineering costs to get the project off the ground would total about $50 million.
The lower Mississippi River supports roughly 136 freshwater fish species, 325 migratory bird species, and 50 mammal species, the Corps said. Eight of those species are federally threatened or endangered, like the pallid sturgeon and the fat pocketbook mussel; several other species are at risk of joining that list.
Climate change is causing more extreme weather, including drought and flooding. Restoring connections between the river and the floodplain is one way the Corps hopes to restore habitats for threatened and endangered aquatic species during extreme weather.
The area is also within the Mississippi Flyway, a migration route that connects central Canada to the Gulf. About 60 percent of all bird species in the country depend on the flyway.
Next steps for ecosystem restoration
Once the Corps reviews public comments, which it’s accepting through March 13, officials will refine the plan and issue a final report to the agency’s Mississippi Valley Division office. If the final plan gets a stamp of approval from the division, it’ll be added to the Water Resources Development Act of 2024 or 2026, depending on the timing.
If Congress approves the act, the Corps will still have to secure funding. It’s a long, arduous process, but if all goes according to schedule, the Corps could start implementing the plan by 2027.
“There’s a long road ahead for this project,” said Marsha Raus of the Corps’ Memphis District.
There are seven other high-priority areas that are in line for a Corps study. With one study under its belt, Raus said, the Corps will find a more efficient method for tackling a wide study area.
Raus said approaching the project with all eight study areas in mind allowed the Corps to see the mosaic of habitats on the lower river, making this proposal the first in a coordinated effort to restore aquatic habitats.
“This is the flagship study for the whole lower Mississippi,” Raus said.
This story is a product of the Mississippi River Basin Ag & Water Desk, an editorially independent reporting network based at the University of Missouri School of Journalism in partnership with Report for America and the Society of Environmental Journalists, funded by the Walton Family Foundation. It was originally published in The Daily Memphian.