Mid-Barataria Sediment Diversion Project


The Mid-Barataria Sediment Diversion project is a component of the Coastal Louisiana restoration strategy that proposes to divert sediment-laden water from the Mississippi River to restore natural deltaic processes and increase land area in the Barataria Basin. Over a 50-year time frame, the project would build and maintain 10,000 to 30,000 acres of upland, and freshwater and coastal marsh habitat, and restore damage to natural resources caused by the Deepwater Horizon oil spill by restoring and preserving critical coastal ecosystems. Confluence is leading the Endangered Species Act (ESA) and Essential Fish Habitat (EFH) consultations, assisting with the Oil Pollution Act (OPA) restoration plan, and contributing to National Environmental Policy Act (NEPA) review associated with the project.

Approach

The ESA biological assessment and EFH assessment that Confluence is managing includes an evaluation of short-term construction effects as well as operational effects over the 50-year design plan for the project. The analytical approach is deconstructing project activities to understand the potential impact mechanisms (e.g., turbidity, salinity change, etc.) as they relate to the species preferences and tolerances as well as alterations to important habitats. This effort is being conducted in close coordination with the Deepwater Horizon Oil Spill restoration plan for the project and a third-party environmental impact statement being developed by the U.S. Army Corps of Engineers to ensure consistent analyses. Confluence is guiding the evaluation of projected impacts to ESA-listed species and EFH habitats using habitat and species model outputs to project long-term operational effects of the project. These analyses focus on ESA listed species including 5 species of sea turtle, 3 bird species, manatee, and pallid sturgeon, and EFH resources such as emergent marshes, submerged aquatic vegetation, soft bottoms, sand/shell, oyster reefs, and water column habitats.

Conclusions

Louisiana’s Coastal Protection and Restoration Authority hopes that land/ marsh retention and growth resulting from sediment diversion projects such as the Mid-Barataria Sediment Diversion will provide communities with sustainability, protection from impacts of storm events and sea level rise, ecological restoration, and boost local economies. With an estimated budget of more than $1.2 billion, the Mid-Barataria Sediment Diversion project’s schedule and activities continue to attract attention and scrutiny from regulatory agencies and the public as the largest sediment diversion project proposed to date. By using best available science and closely coordinating the NEPA and ESA processes with each other and with the OPA restoration plan, the ecological analyses will provide decision makers and the public detailed and accurate information with which to base their conclusions.

Project Location
Plaquemines Parish, Louisiana

Client
Louisiana Coastal Protection and Restoration Authority

Project Timeline
Ongoing since 2018