The Dauphin Island Causeway Shoreline Restoration Project is restoring 80 acres of salt marsh habitat along 3.5 miles of shoreline in Mobile Bay. The purposes of the project are to restore eroded marsh habitat and provide resilience to the Causeway, the sole evacuation corridor from Dauphin Island to mainland Mobile County that is frequently overtopped during storm events. The project is funded by NFWF’s Gulf Environmental Benefit Fund (GEBF) and Emergency Coastal Resilience Fund (ECRF), and is one of the largest and most significant investments in an Alabama coastal restoration project to date.

The project is being constructed in three contract phases. The Phase 1 contract was administered by Mobile County to construct segmented low-crested breakwaters to protect the restored habitat and roadway and provide containment during the marsh fill construction activities. In Phase 2, over one million cubic yards of material dredged from the Mobile Harbor Deepening Project was beneficially used to restore habitat through an agreement between the County and the USACE Mobile District. The sandy material was used to construct a sand berm along the landward side of the breakwaters, providing additional containment and forming high marsh and beach ridge habitat. The material with higher fines content was placed landward of the sand berm as marsh fill. Finally, the County will administer the Phase 3 contract to install vegetative plantings, excavate tidal creeks, and perform other habitat enhancements, which may include additional BU placement to increase habitat sustainability.

This project’s success was highly dependent upon the close coordination of Mobile County, ADCNR, USACE Mobile District, and Mobile County’s consultants. This presentation will discuss the coordination efforts that were made to bring this project to fruition, key design features that enabled efficient beneficial use, permitting constraints, construction challenges, and lessons learned for successful BUDM.