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Louisiana is officially sinking

Posted: 5:18 PM, Jul 16, 2019
Updated: 2019-07-16 18:18:29-04
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The state of Louisiana is officially sinking.

29 years ago, the National Geodetic Survey last measured the state's subsidence. This first observation took place at the University of New Orleans in 1989.

This past year, with the help of LSU's Center for Geoinformatics, the Survey completed four absolute gravity observations and the results show the difference in the state's elevation.

LSU Chief of Geodesy Cliff Mugnier said that the cumulative change in elevation is 147 mm in 29 years.

That's 5mm a year.

The study showed that Baton Rouge, Lafayette, Oakdale, Hammond, and Shreveport have remained virtually unchanged.

Alexandria, Old River, Lake Charles, Boothville, and Ruston all subsided to some degree, while some places instead gained ground.

These include Thibodaux, Siciliy Island, Rayville, and Natchitoches.

Mugnier said changes can be a result of variations in groundwater and tectonic motion.

The LSU Center for Geoinformatics has a three-person permanent crew that travels to all their reference sites statewide to observe and note changes.

Mugnier said, "These observations are expected to contribute to the knowledge of the surface motions of the state."