Official Site of The State of New Jersey
In Spring 2019, the U.S. Army Corps of Engineers (USACE) Philadelphia District partnered with New Jersey Fish and Wildlife, The Wetlands Institute, and the USACE Engineer Research and Development Center to establish the Seven Mile Island Innovation Laboratory (SMIIL). This initiative aims to advance and improve dredging and marsh restoration techniques. Since its inception, SMIIL projects have restored over 85 acres of marshland and protected two island complexes from further degradation.
The Scotch Bonnet Island project will enhance tidal marshes struggling with rising sea levels by adding supplemental sediment to Scotch Bonnet Island in Cape May Coastal Wetlands Wildlife Management Area. Clean sediments dredged from the NJ Intracoastal Waterway (NJIWW) will be used to raise low marsh areas that have sunk below optimal levels. These sediments will fill in expanding pools, thereby strengthening the ecosystem’s resilience. The project builds upon the success of previous beneficial use projects in coastal New Jersey.
Approximately 25,000 cubic yards of sediment from a critical shoal in the NJIWW federal channel will be hydraulically pumped onto the marsh platform to increase its elevation. The goal is to uplift a 12-acre area. Biodegradable coir logs will be used to direct sediment flows into lower-lying areas and prevent sediment loss to non-target areas. Tidal flooding will naturally distribute the sediments across the marsh platform.
The USACE Philadelphia District, USACE ERDC, US Naval Academy, University of Pennsylvania, and The Wetlands Institute are involved in monitoring the site and placement efforts. They will document conditions before and during sediment placement and monitor the marsh’s response and recovery, as well as usage by diamondback terrapins and various migratory birds.
Project implementation is expected to begin in October 2024.
