Stabilization of Eroding Shorelines in Estuarine Wave Climates with Constructed Fringe Wetlands Incorporating Offshore Breakwaters
Scott L. Douglass and Judy P. Stout
University of South Alabama, Mobile AL 36688
We are investigating the use of low-crested offshore breakwaters in the construction of fringe wetlands. Breakwaters can protect constructed wetlands from waves until the root/rhizome mat is established. Preliminary evidence suggests that a very small amount of wave attenuation can be very beneficial to a natural wetland along the shoreline of a bay or bayou. Although some engineering guidance exists for the functional design of offshore breakwaters for beach creation, guidance for their use for wetlands stabilization is very limited. This research will evaluate the existing engineering tools for estimating wave attenuation by low-crested breakwaters within the context of the storm wave and water level climate of the Gulf of Mexico estuaries. The field research component of the research will be to monitor the physical and biological behavior of two constructed, fringe wetlands that are protected by breakwaters on Mobile Bay. One of these wetlands will be constructed as part of this research using sand-filled geotextile tube breakwaters. The ultimate goal of this research is to develop guidance for the consideration and construction of this type of fringe wetland as an alternative to bulkheads for shoreline stabilization.