Barrier Islands are the first line of defense against storms for the mainland, and the resilience of these islands is essential for protection of the ecosystems and communities along the coast. These islands also provide feeding and breeding habitats for shorebirds, seabirds, and other sea animals and vegetation. Barrier islands are dynamic by nature, changing, sometimes disappearing, but returning with the course of nature. However, they have been rapidly disappearing and not recovering due to a combination of storms, erosion, sea level rise, construction, and oil spills.
The state of Louisiana has been mitigating land loss on its coastal islands by depositing dredged sand onto the island platforms. This study looks at four islands in the Louisiana Outer Coast Restoration Project to assess the positive land change and persistence of the restorations by comparing pre-restoration orthophotos (2013) with post-restoration orthophotos (2021 and 2022) to detect land change.
Results show the growth of the islands due to the restoration and that a range of 86% to 100% of the reported added land area has persisted in the time since restoration completion despite a number of severe tropical storms in the area during this time frame.