Coastal erosion in Louisiana

Coastal Erosion in Louisiana is the process of steady depletion of wetlands along the state's coastline in marshes, swamps, and barrier islands, particularly affecting the alluvial basin surrounding the mouth of the Mississippi River at the foot of the Gulf of Mexico on the Eastern half of the state's coast. In the last century, Southeast Louisiana has lost a large portion of its wetlands and is expected to lose more in the coming years, with some estimates claiming wetland losses equivalent to up to 30 football fields per day. One consequence of coastal erosion is an increased vulnerability to hurricane storm surges, which affects the New Orleans metropolitan area and other communities in the region. The state has outlined a comprehensive master plan for coastal restoration and has begun to implement various restoration projects such as fresh water diversions, however certain zones will have to be prioritized and targeted for restoration efforts, as it is unlikely that all depleted wetlands can be rehabilitated.

The process of coastal erosion is the result of various factors, particularly the blockage of traditionally occurring deposits of fresh water and silt from the river caused by man-made levees which have been built up and down most of the river over the last century, which now impede the river's ability to replenish its southernmost alluvial plains which are constantly dependent on the infusion of the river's once plentiful deposits which usually occurred during annual high stage floods in the springtime, the kind of which the river-levees now serve to buffer against for the protection of residents, livestock, and property residing in regions adjacent to the river throughout the Mississippi River valley. The deterioration results in the death of fresh and brackish water plants historically part of the ecosystem, which are not only a vital feature of the wetlands' topography, but also serve to capture silt, and thus are needed to build up and sustain marsh structures. As fresh and brackish water plant habitats recede, salt water from the Gulf of Mexico further encroaches, killing off more non-saltwater plants, thus further eroding pre-existing mud formations which these plants had once supported.

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