Sand resources, regional geology, and coastal processes for the restoration of the Barataria Barrier shoreline

Abstract

Louisiana's barrier shorelines are rapidly eroding due to high rates of relative subsidence combined with sea-level rise, repeated storm impacts, and a diminishing sand supply. Due to these factors Louisiana's barrier shorelines are the fastest eroding shorelines in the Nation. In places, the erosion of barrier islands exceeds 65 ft/yr (20 m/yr). One of the best methods for protecting Louisiana’s coastal resources from encroachment from the sea is shoreline restoration using coastal and nearshore sediment sources. The key to restoring barrier shorelines is to find large volumes of high-quality sand and developing cost-effective shallow delivery systems to move these materials. The first major barrier shoreline restoration project proposed by Coast 2050 planners is for the Barataria Basin barrier shoreline that stretches 50 mi (80.5 km) from Belle Pass east to Sandy Point. Many of the barrier shoreline areas in Barataria Basin have become fragmented, low mounds of sand, that are easily washed over by minor storm events, that provide less available habitat than fully developed barrier islands. The objective of this study is to provide information about sand resources, coastal processes, and regional geology which can be collectively used to restore the Barataria Basin barrier shoreline. The focus of this study is the identification of sand resources for the restoration of beaches and creation of backbarrier marshes along this portion of the coast.