Records show that Texas Brine Co. has developed a backup plan to replace the cracked southern section of a protective levee surrounding the sinkhole in Louisiana’s northern Assumption Parish and may look to reroute Bayou Corne if conditions deteriorate further.
The Advocate reports the company’s new draft plan proposes “triggers” that would prompt the levee replacement. It also outlines an alternative of rerouting Bayou Corne if a replacement levee proves too unstable to maintain due to sinking of the remaining land between the sinkhole and the bayou.
Company officials and regulators say it is unlikely there would be a need to reroute the bayou based on current projections for the sinkhole’s expansion but need to be prepared.
Bayou Corne runs just south of the levee’s southern segment and forms half of a semi-circular arc of waterways south of La. 70. Bayou Corne ultimately joins Grand Bayou, which flows south to Lake Verret.
The sinkhole was dormant for weeks this fall, but has rumbled back to life twice since late October. Spikes in “micro-earthquakes” have resulted in cracks and sinking in a section of the levee’s southern arm.
As the 26-acre, lakelike hole has edged toward the southern levee and the bayou beyond, Texas Brine had been under growing pressure from regulators, parish government officials and the remaining residents in the Bayou Corne community to lay out contingency plans in the event the sinkhole expands farther to the south.
Scientists think the breach of an underground salt dome cavern operated by Texas Brine last year unleashed percolating methane gas from natural deposits and caused the sinkhole to emerge between the Bayou Corne and Grand Bayou communities probably on Aug. 3, 2012.