Louisiana Sinking, A Third Of State’s Coast Could Vanish By 2050
The state of Louisiana lost some 1,900 square miles of coastal land in the 20th century and could lose another 700 square miles by 2050 if no new restoration takes place, say federal and state scientists.
Most of the land lost and under threat is coastal marsh land, according to data from the U.S. Geological Survey (USGS), and without a coordinated effort one third of coastal Louisiana will have vanished into the Gulf of Mexico by 2050.
The 1,900 square miles lost between 1932 and 2000 is an area roughly “the size of the state of Delaware,” said James Johnston, spatial analysis branch chief at the USGS National Wetlands Research Center.
Based on USGS data, land loss rates have been reduced from 39 square miles per year between 1956 and 1978 to 24 square miles per year from 1990 to 2000. For the entire period, the loss rate has been 34 square miles per year.
Reversing this trend will not be easy, as USGS documented in a peer-reviewed report to be released soon. The report analyzes the recent work of the Louisiana Coastal Area Land Change Study Group, which includes federal and state government agencies and university experts in remote sensing, geographic information systems, ecosystem processes, and coastal land loss.
Data generated from the report indicates that restoring the state’s coast will be one of the largest environmental projects ever undertaken in the United States, estimated to cost $14 billion over the next 40 years. State and federal officials, however, estimate that the cost of inaction will amount to more than $100 billion in infrastructure alone.
The report cites many causes of wetland loss, but chief among them are the dams, levees, navigation projects and channels erected along the mainstream and major tributaries of the Mississippi River. These projects, started in 1928 following the watershed flood of 1927, were completed in 1963, coinciding with the first observations of major coastal land loss in Louisiana.
They have resulted in a 67 percent decrease in sediment delivered to the Louisiana coast, a necessary process to keep marshlands replenished.
The continued loss of the states’ coastal wetlands could have severe ecological, economic and human impacts.
Louisiana’s coastal wetlands make up the seventh largest delta on Earth and contain some 40 percent of U.S. tidal marshes and support the largest commercial fishery in the lower 48 states. The wetlands provide critical habitat for millions of waterfowl and migratory birds, as well as for several endangered and threatened species.
The entire region helps buffer larger populations and property in the state’s coastal cities, including New Orleans, from hurricanes and other storms. The U.S. Census Bureau finds that about half of the state’s 4.5 million residents live in coastal areas.
Provided by theEnvironmental News Service.