Mid-Breton Sediment Diversion

Sediment Diversion

The Mid-Breton Sediment Diversion is a vital project aimed at reducing land loss in the Breton Basin, one of the most productive and ecologically diverse areas on the Gulf coast. This proposed diversion will be on the east bank of the Mississippi River at Wills Point in Plaquemines Parish.

This diversion, like other planned sediment diversions, will use the power of the Mississippi River to move sediment and fresh water from the river into nearby basins, mimicking nature’s historic land-building processes. As soon as it begins operating, the Mid-Breton diversion will begin depositing sediment and benefiting marshes that have been sediment-starved since levees were built almost 100 years ago. The diversion is projected to build and maintain almost 16,000 acres of new land in the Breton Basin during its first 50 years of operation, with the potential to restore almost 67,500 acres of marsh in the Breton Sound Basin in total.

Mid-Breton will complement other project types in the basin, such as marsh creations and ridge restorations, by protecting these projects and extending their lifespan. The addition of sediment and nutrients from the river will gradually increase soil strength, improving existing marshes in the basin and providing greater diversity of habitat for wildlife such as deer, wintering ducks, alligators, largemouth bass and crawfish. Most importantly, these wetlands also provide an important line of defense against storm surge for local communities and the larger New Orleans metro region.

As land is built, the project will also restore the wide range of salinity in the estuary, which contributes to the high productivity of habitats for many fish, bird, and marine species, many of which local communities may rely on. In the long term, the Mid-Breton diversion is an essential component of the 2023 Coastal Master Plan to restore land and increase community resilience in the face of sea level rise, hurricanes, and other environmental challenges.

The Mid-Breton Diversion is part of CPRA’s Mid-Basin Sediment Diversion Program, which includes the larger Mid-Barataria Sediment Diversion. As Mid-Barataria advances through the implementation process ahead of Mid-Breton, it will provide lessons learned for this similar though slightly smaller project.

What does a future without action look like?

What does a future without action look like?	What does a future with action look like?

About This Project

Project ID: CMP17: 001.DI.104

Type: Sediment Diversion

From the 2023 Coastal Master Plan

For the first time, two large-scale sediment diversions off of the Mississippi River — the Mid-Barataria and Mid-Breton Sediment Diversions — are included in Future Without Action (FWOA). These projects, when implemented, will divert sediment and water from the river when flows are favorable to transport sediment and deliver it to the Barataria and Breton basins, respectively. The two mid-basin sediment diversions are anticipated to reconnect the adjacent basins to the Mississippi River as a source of sediment to nourish and maintain existing wetlands and to create coastal wetlands over time, in much the same way as southeast Louisiana was originally built by the Mississippi River before levee construction

From the 2024 Annual Plan

FY 2025 Status: In E&D
Funding Source: NFWF
FY 2025 Expenditures: $20.3 million
Estimated Cost: $799 million

This project involves the construction of a sediment Diversion with a maximum capacity of 35,000 cfs on the east bank of the Mississippi River in the mid-Breton Basin in upper Plaquemines Parish. When in operation, the project would transfer sediment-laden water from the Mississippi River through a self-contained channel before outfalling into the basin.

Project Updates

06/14/2024
The Executive Director of the Permitting Council granted a U.S. Army Corps of Engineers request to extend several final completion dates for the Mid-Breton Sediment Diversion project, with a new target date of May 2025. (determination on request)
06/04/2024
The U.S. Army Corps of Engineers is expected to release the Draft Enviornmental Impact Statement (DEIS) in July 2024, with the Final EIS (FEIS) expected in September 2025.
08/03/2020
U.S. Army Corps of Engineers updated the status and shared the implementation timeline of the Mid-Breton Sediment Diversion on the Federal Permitting Dashboard. The update indicates that the expected release of the draft environmental impact statement for this project will be November 2022, and a record of decision is expected by February 2024. (press release)
02/14/2019
Louisiana’s Coastal Protection and Restoration Authority (CPRA) announced today that the United States Army Corps of Engineers (USACE) has approved its request to include the Mid-Breton Sediment Diversion on the Federal Permitting Dashboard. (press release)
01/16/2019
Louisiana Coastal Protection and Restoration Authority (CPRA) announced that the agency will expand the study for the Mid-Breton Sediment Diversion from 35,000 to 75,000 cubic feet per second (cfs). (press release)

What is a Diversion Project?

Graphic by SCAPE, Published in 2023 Coastal Master Plan

Diversions mimic nature’s historic land-building processes by using the power of the river to move sediment and fresh water from the river into nearby basins. This project type can not only build new land but also provide a sustainable source of sand and mud necessary to sustain and increase the health of existing wetlands over time. Sediment diversions can also re-establish or maintain the fresh end of the estuary, originally lost to saltwater intrusion, ensuring that the range of fresh to saltwater habitats that makes Louisiana’s estuaries so productive persists into the future. Sediment diversions also help sustain nearby marsh creation, barrier island and ridge restoration projects.