The Louisiana Trustee Implementation Group, the agencies charged with restoring Louisiana’s natural resources after the 2010 Deepwater Horizon oil spill, has approved $2.26 billion in funding for the Mid-Barataria Sediment Diversion project. The implementing partner, the Louisiana Coastal Restoration and Protection Authority (CPRA), will use the funding to construct a large-scale sediment diversion to reconnect the Mississippi River to Louisiana's Barataria Basin estuary.
The project represents one of the largest and most innovative coastal habitat restoration efforts ever undertaken. Intended to re-establish historic delta land-building processes by allowing for the controlled release of freshwater, sediment, and nutrients from the Mississippi River into the Barataria Basin estuary, the project will support ecosystem-scale restoration of the estuary and its wetlands.
The Louisiana Trustee Implementation Group finalized its funding decision based on the September 2022 Mid-Barataria Sediment Diversion (MBSD) Final Restoration Plan (PDF, 1,123 pages). In that Plan, the Louisiana Trustees evaluated a range of alternatives for the diversion, and the benefits and impacts of the project. The February 1, 2023 funding decision implements the Louisiana Trustees’ selection of the preferred project at River Mile 60.7 in Plaquemines Parish, Louisiana.
Once constructed, the project is intended to re-establish historic deltaic processes by allowing for the controlled release of up to 75,000 cubic feet per second of water, sediments, and nutrients from the Mississippi River into the Barataria Basin estuary.
Over 50 years, the sediment carried by the project is projected to restore over 13,000 acres of wetland habitat—which is 20 square miles, or the size of Breton National Wildlife Refuge. These restored wetlands are intended to contribute to protecting communities and infrastructure, reducing impacts from storms, supporting healthier Gulf fisheries, and benefiting many species important to the region’s economy and environment.
The Trustees recognize that the scale of the project will result in adverse impacts to those natural resources that rely on higher salinity waters, particularly dolphins, brown shrimp, and oysters. The project will also increase water levels in the vicinity of the diversion. The Louisiana Trustee Implementation Group's funding decision includes $378 million dedicated to mitigation and stewardship measures to minimize impacts where possible.
Restoration Plan Evaluation and Timeline
The funding decision is the final step in the Louisiana Trustees’ evaluation of the Mid-Barataria Sediment Diversion under the Oil Pollution Act. This is the culmination of six years of work focused on the Barataria Basin that began in May of 2017.
The Louisiana Trustees participated in the U.S. Army Corps of Engineers’ evaluation of the environmental impact of the Mid-Barataria Sediment Diversion Project. In December 2022, the Army Corps released their Records of Decision and issued permits and permissions to CPRA to construct and operate the diversion.
CPRA and the National Oceanic and Atmospheric Administration (NOAA) are the lead Trustees for this Final Restoration Plan, which was prepared jointly with the other Louisiana Restoration Area Trustees: the U.S. Department of the Interior, the U.S. Environmental Protection Agency, and the U.S. Department of Agriculture.
Historic and Environmental Context
Louisiana’s wetlands act as critical foraging, nursery, and nesting grounds for hundreds of species of fish and other wildlife. The 2010 Deepwater Horizon oil spill was the largest in U.S. history, impacting the entire northern Gulf of Mexico ecosystem.
The wetlands in the Barataria Basin estuary were among the most heavily impacted. The oil spill and response accelerated an ongoing trend of coastal land loss, especially in the state’s Barataria Basin estuary. The species, fisheries, and communities that rely on estuarine habitats face serious challenges due to the continued loss of wetlands, increasing estuarine salinities, as well as sea level rise, and land subsidence.
Since the Deepwater Horizon oil spill, the Louisiana Trustees have approved 78 restoration projects. Several are currently underway in the Barataria Basin estuary, including the Upper Barataria Marsh Creation and Spanish Pass projects.
More Information and Plan Documents
- Record of Decision (PDF, 466 pages)
- Final Phase II Restoration Plan #3.2: Mid-Barataria Sediment Diversion Restoration Plan (PDF, 1,123 pages)
- Executive Summary (English, PDF, 4 pages; Spanish, PDF, 5 pages; Vietnamese, PDF, 4 pages)
- Mid-Barataria Sediment Diversion Fact Sheet (PDF, 3 pages)
- U.S. Army Corps of Engineers Final Mid-Barataria Sediment Diversion Project Environmental Impact Statement