As river rises, flood structure will be closed

With the Atchafalaya River on the rise, local officials plan to close the Bayou Chene Flood Control Structure on Monday, protecting bayou-side residents from back-flooding.
The St. Mary Levee District announced Wednesday that the structure will be closed beginning at 7 a.m. Monday. No traffic on the bayou will be allowed after that time.
“If you have assets that you need to get in or out of the system please do it before then,” the Port of Morgan City said in an email Wednesday.
“Currently we are not sure of the duration of the closure. Looking at current predictions, we can assume a couple of weeks. We will re-open the structure as soon as conditions are safe. “
Closing the structure is expected to take about five hours.
The National Oceanic and Atmospheric Administration gauge at Morgan City said the Atchafalaya was at 3.8 feet Thursday. It’s expected to rise to the 6-foot minor flood stage by early Wednesday and to the 7-foot moderate flood stage by early Monday, April 21.
The NOAA predicts a crest of 7.2 feet at midday Tuesday, April 22.
The procedures for operating the Flood Control Structure call for the issuance of a notice of intent to close when the stage reaches 6 feet. The trigger point for closure is 7 feet.
After the crest, the structure will be opened when the Bayou Penchant gauge is 4 feet or lower and the difference between the stages on the flood and protected sides of the structure is 1 foot or less.
The heart of the Flood Control Structure is a 400-foot barge, constructed at Bollinger’s Amelia facility, that can be moved into place across the bayou to block flooding.
The structure was built after a series of floods 2011-19. In order to protect interests along the bayou from flooding, local officials sank barges across the bayou at a cost of millions each time.
The structure is an $80 million solution to that problem. The structure, financed by the Coastal Protection and Restoration Authority and operated by the Levee District, was dedicated in 2022.
Portions of the lower Mississippi and Ohio valleys have been drenched by heavy rain this spring. The water flows into the Mississippi River, and 30% of the flow is diverted into the Atchafalaya.
Warren County, Mississippi, officials, based in Vicksburg, declared a state of emergency Wednesday as the Mississippi heads toward an expected crest of 48.5 feet, about 1.5 feet short of the level that causes major flooding.