The Mid-Barataria Sediment Diversion

MBSD is a State Priority But It Isn’t Costing Taxpayers

The state must uphold CPRA’s mandate to protect Louisiana’s coast and the state’s business climate.

1. Conserving Louisiana Working Coast is a State Priority: Following the devastating hurricanes of 2005, the Coastal Protection and Restoration Authority (CPRA) was created as Louisiana’s lead agency for coastal protection and restoration, establishing concrete action steps through the creation of the Coastal Master Plan. Independent polling conducted in 2025 found that 83% of Louisiana residents support the MBSD. In Plaquemines and St. Bernard, 85% of residents polled supported sediment diversions.

2. MBSD is Fully Funded through the Deepwater Horizon Settlement: MBSD’s funding does not come from taxpayer dollars, but through the RESTORE Act created after the BP spill. These funds follow a strict federal-state process. Abandoning or modifying MBSD would burden the state with paying back the already-spent $600 million from the state’s general fund. It would also freeze the remaining $2.4 billion until a new project could be proposed, evaluated and permitted and there is no guarantee Louisiana would hold onto these funds.

3. CPRA’s Reversal Could Risk State Authority: CPRA is the single entity responsible for coastal restoration projects like MBSD. Local parish governments cannot legally override this authority. By taking this project to court, CPRA risks setting a precedent that weakens state authority over parishes and emboldens individuals on other issues such as education or public safety.

Protecting Lives and Homes from Hurricanes and Flooding

1. Flood Protection for Greater New Orleans: MBSD will create a natural flood buffer zone to manage sea level rise and extreme storm surges, reducing flood risk for 1.2 million people in greater New Orleans, protecting lives, homes and businesses.

2. Support for Westbank Parishes: As part of MBSD, $378 million will be provided to West Bank parishes to raise homes or relocate them to safer areas, further reducing flood risk.

Nature, Science and Process Prove MBSD Works

Decades of world-class, best-available science and 50,000+ public comments back MBSD. Substitutions or alternative proposals lack evidence of success.

1. Louisiana’s Best Land-Building Tool: The Mississippi River built up coastal Louisiana by depositing sediment and fresh water over thousands of years. Mimicking that process is the only way to rebuild coastal wetlands durably at scale. A critical proof point—the only areas gaining land in Louisiana today are places that receive river inputs, such as the Atchafalaya Bay.

2. Wetlands Protect Against Hurricanes, Storms and Everyday Flooding: Wetlands, such as MBSD will build, act as a sponge to trap and slowly release water, reducing flooding in communities.

3. Land Loss will Continue without MBSD: Without intervention, Plaquemines Parish could lose as much as 55% of its land area over the next 50 years, bringing sea level rise closer to New Orleans. Only MBSD addresses this problem at its root.

4. More Durable than Dredging: Dredging, an alternative suggested, is a short-term solution (20 years), that would start eroding again as soon as the pumps turn off. MBSD reintroduces sediment and freshwater naturally and continuously for at least 50 years.

More Cost-effective and Longer Lasting than Dredging

Dredging projects are short term solutions that do not address the root cause of the problem—sediment starvation, subsidence, lack of freshwater, and sea level rise. Dredging projects begin to sink as soon as the pumps turn off and are only expected to have a 20-year lifespan. The diversion reintroduces sediment and freshwater in a way that can combat sea level rise and subsidence nourishing both naturally built and dredged wetlands as long as it continues to run—at least fifty years.

CPRA estimates it would cost ~$5 billion to create as much land as MBSD through dredging and the process would need to be done again after 20 years, doubling the overall cost.

Economic Benefits to Louisianians

1. Jobs and Revenue: MBSD will generate $1.9 billion in Plaquemines Parish business sales, $308.2 million in household income and support 540 jobs annually over the construction period. Regionally (Plaquemines, St. Bernard, Orleans, Jefferson, St. Tammany), it will generate $2.8 billion in sales and 3,095 jobs.

2. Reduced Insurance Costs: Increased coastal buffer zones will reduce flood insurance costs for residents in the greater New Orleans area.

3. Improved Commercial and Recreational Fisheries: MBSD will improve the productivity of the higher value white shrimp as well as crawfish, key commercial fisheries in the state. It will also improve habitat and increase population sizes for largemouth bass, red drum and other fish species, bolstering the outdoor recreation industry in the state.

Robust Mitigation Measures to Reduce Impacts to Fisheries

1. Short-term Impacts: MBSD is expected to alter the salinity of the Barataria Basin. This will impact a portion, just over one-third, of Louisiana’s oyster fishery in the near-term. The fishery is not expected to experience serious losses over the lifetime of the project.

2. Significant Mitigation Funds: MBSD is providing $53 million to support oyster fishers affected by the project to shift oyster grounds, not halt them. Fishers will help control how funds are spent, whether that is building new or enhancing depleted oyster reefs, or evolving the aging workforce or improving gear.

3. Oyster Farming Already in Decline: Oysters are already under threat from environmental changes. Without MBSD, the oyster fishery will continue its decline as more marsh converts to open water, the basin’s water grows saltier, and temperatures change. MBSD’s mitigation funds will help the industry adapt to these changes long-term.

What’s the Latest on the Project and What Can You Do?