The Lake Pontchartrain and Vicinity, Louisiana (LPV) Project provides coastal storm risk management for the greater New Orleans area on the east bank of the Mississippi River.
The project was built to reduce flood risk from a 1% annual exceedance probability (AEP) storm surge and wave event. Southeast Louisiana faces ongoing challenges from weak soils, regional subsidence, and the global effects of sea level rise. These factors were fully accounted for in the original LPV system design. For this reason, floodwalls within the system were constructed to elevations that factored in projected relative sea level rise through the year 2073. From the outset, it was understood that levees would require future "lifts"— or height increases — to maintain performance over time.
The need for future levee lifts was always part of the LPV system's lifecycle planning. Construction of levees in lifts is typical in south Louisiana in order to take advantage of soil strength gains over time. Those gains allow designs with a smaller cross-sectional area which minimizes costs by reducing the amount of borrow or clay material required and mitigation costs by reducing the levee’s footprint. Following extensive analysis, USACE completed a General Reevaluation Report (GRR), and in 2023, a Record of Decision (ROD) was signed endorsing the planned lifts as the long-term solution for sustaining the system’s 1% level of risk reduction.
Overview / Authorization
In WRDA 2024, Congress authorized construction as identified in the Director’s Report signed Dec. 17, 2021, and the Environmental Impact Statement (EIS) Record of Decision signed October 16, 2023. The authorized work will follow a 65% Federal and 35% non-Federal cost share structure and the fully funded cost estimate for multiple lifts over 50 years is $3.5B.
The non-Federal Sponsors are the Coastal Protection and Restoration Authority Board of Louisiana, Pontchartrain Levee District, and Southeast Louisiana Flood Protection Authority-East.