As part of the DARPA Reefense program, a new type of living shoreline was built in St. Andrew’s Bay, Florida. This living shoreline includes artificial reefs, vegetation patches, and small landscape features designed to reduce flow energy and protect the coastline.

Here, we studied how this living shoreline affected the nearby coastline in the short-term, by measuring flow characteristics and sediment movement before and after installation of the Reefense project. Study results highlighted water flow was slower and less turbulent after installation, denoting how the living shoreline helps attenuating the incoming flow. Local acceleration also occurred within the living shoreline, which likely induced small areas of scour. However, sediment deposition was enhanced up to 50 cm within the living shoreline, suggesting the sedimentation overcomes local scours. The area not covered by the living shoreline showed less predictable changes, both erosion and deposition.

Overall, the observed short-term effect of the living shoreline was to attenuate incoming flow and promote sediment deposition. Ongoing monitoring will help understand long-term benefits