Corps releases West Shore Lake Pontchartrain environmental documents for review

Published Dec. 2, 2022

NEW ORLEANS – The U.S. Army Corps of Engineers, New Orleans District released today the Final Supplemental Environmental Impact Statement to the "2014 Final Integrated Feasibility Report and Environmental Impact Statement for the West Shore Lake Pontchartrain Hurricane and Storm Damage Risk Reduction Study" for a 30-day public review.

The Final Supplemental Environmental Impact Statement (FSEIS), which includes the Final Clean Water Act Section 404(b)(1) Evaluation, is available for public review through Jan. 3, 2023.

The FSEIS evaluates, at the request of the non-federal sponsor, an alternative project to compensate for unavoidable impacts to swamp habitat associated with the construction of the West Shore Lake Pontchartrain Hurricane and Storm Damage Risk Reduction Project (WSLP Project).


Findings in the documents indicate the non-federal sponsor’s Maurepas Swamp Alternative 2 (MSA-2) satisfies the mitigation needed by the WSLP project and is recommended as the Tentatively Selected Alternative (TSA). While the New Orleans District commander recommended MSA-2 as the TSA, the ultimate decision on which mitigation plan to implement will be made by the Mississippi Valley Division commanding general.


The proposed action, MSA-2, is a 2,000 cubic foot per second freshwater diversion from the Mississippi River into the Maurepas Swamp. The diversion would be operated yearly, as Mississippi River water levels allow, to provide benefits to existing swamp habitat within the mitigation area. The MSA-2 could generate approximately 1,240 Average Annual Habitat Units of coastal zone swamp offsetting the 947 units needed for the WLSP project.

The conveyance channel would be located on the East Bank of the Mississippi River in St. John the Baptist Parish, immediately west of Garyville, LA, and would encompass Hope Canal. The embankment features would be located in St. John the Baptist and Ascension Parishes, and the weirs would be located within Bayou Secret and Bourgeois Canal, located in St. James Parish.

The FSEIS and Final 404(b)(1) are available online on the New Orleans District website at: The 30-day review period will begin Dec. 2, 2022 and end Jan. 3, 2023.


Matt Roe

Release no. 22-026