Hydrodynamic Change Following Living Shoreline Restoration Based on a Before-After-Control-Impact Experiment

摘要

Preventing shoreline erosion is critically important as coastal hazards intensify. Living shoreline stabilization protects vulnerable coastal assets while promoting biodiversity. However, increased understanding of impacts to physical processes could improve restoration designs. This before-after-control-impact study quantifies hydrodynamic change resulting from restoring a degraded estuarine shoreline using living shoreline techniques. The eroding shoreline, located in Florida's Mosquito Lagoon, was restored using oyster shell bags and emergent vegetation. Hydrodynamic data were collected from three shoreline sites (the Restored shoreline, a Control degraded shoreline, and a control Reference shoreline stabilized by mature mangroves) before and after living shoreline implementation. We find immediate and pronounced hydrodynamic effects attributed to restoration. Incoming velocities were reduced in the Restored site soon after restoration and significant wave heights were attenuated by the living breakwaters. Notably, onshore-offshore gradients of mean velocities and turbulence statistics within the restored site differed from the reference shorelines.