Land Loss Facts

Coastal Louisiana is facing a land loss crisis: Since the 1930s, the state has lost nearly 1,900 square miles of land to open water.

This land loss continues today, with coastal Louisiana losing land at the rate of one football field every hour. As a result, our coast is increasingly vulnerable to the effects of sea level rise, subsidence and storm events, leaving communities and businesses in coastal Louisiana at risk.

The Untold Story — Disappearing Louisiana Wetlands

Louisiana's land loss is the product of a number of natural and man-made causes. Extreme storms, rising sea level, and changes in hydrology due to extensive canal dredging are all contributing factors. Although this crisis cannot be attributed solely to any one cause, land loss has been exacerbated by modifications to the river which have effectively cut it off from its delta.

In a naturally functioning delta, the river will overflow its banks during flood events, allowing the sediment carried within the water column to settle into the adjacent marshes and build land. Instead of nourishing its delta, the lower Mississippi River is now significantly altered and shunts its sediment-rich waters deep into the Gulf of Mexico. Without this influx of sediment to the wetlands of coastal Louisiana, the processes of subsidence and sea level rise dominate, and land is rapidly disappearing.

Additional causes of land loss in the Mississippi River Delta include invasive species, such as nutria; dams on rivers upstream; and disasters such as the BP oil spill.

More information on Louisiana land loss from the US Geological Survey.