Coastal Protection and Restoration Authority to Begin Sediment Diversion Project to Restore Wetlands

The Coastal Protection and Restoration Authority (CPRA) is working with the Louisiana Department of Wildlife and Fisheries and other natural resource agencies, to design two coastal restoration projects. The Mid-Barataria and Mid-Breton sediment diversions will establish a controlled and permanent connection between the Mississippi River and the coastal wetlands on either side of Plaquemines. Since the Mississippi River was leveed in the 1930s, the Barataria and Breton Basins and Mississippi River Delta have lost approximately 700 square miles (or 447 thousand acres) of land, representing one of the highest land loss rates in the world, through sediment deprivation, hydrologic alteration, subsidence, sea level rise and saltwater intrusion.

CPRA has selected the Archer Western-Alberici Joint Venture to provide Construction Management At-Risk (CMAR) services for the Mid-Barataria Sediment Diversion Project under a $13.8 million contract. The CMAR model in Louisiana involves two contracts:  a pre-construction phase contract and construction phase contract. The scope of this contract includes participation in the design process of the project. Once the design is complete, CPRA will negotiate a Guaranteed Maximum Price (GMP) of construction with the Archer Western-Alberici. If negotiations are successful, the construction phase contract will then be awarded for the agreed upon GMP.

The Mid-Barataria Sediment Diversion will provide sediment, water and nutrients from the Mississippi River to the Barataria Basin to build, maintain and sustain wetlands. The project will be located in Plaquemines Parish, Louisiana, along the west bank of the Mississippi River, just north of Ironton and south of the Phillips 66 Alliance Refinery, near Mississippi River Mile 61.

Through the 2017 Coastal Master Plan, the state has identified $6.6 billion in projects to build or maintain land and reduce flood impacts in Plaquemines. This includes ridges, marsh creation, shoreline, structural and nonstructural protection, and sediment diversions.
The construction is being done under Deepwater Horizon oil spill funds and is anticipated to invest about $2 million to the local economy. For more details on projects already completed, see the article in the March/April issue, “CPRA Approves FY19 Annual Plan; $17.7B for Marsh Creation.”