A major state highway in Assumption Parish that was closed Saturday — after officials said an underground bent natural gas pipeline posed an explosion risk — may reopen by midnight Sunday.
Parish authorities shut down La. 70 over a four-mile stretch in Pierre Part and Bayou Corne after they discovered that when a sinkhole formed overnight Thursday, the natural forces that were unleashed bent the underground natural gas pipeline.
Authorities said while the bent 36-inch pipeline was not leaking, it still posed an explosion risk.
As a result, Crosstex Energy L.P. of Dallas, which owns the pipeline, began Saturday depressurizing the bent pipeline. Also, three other natural gas companies with pipelines near the bent pipeline are depressurizing their lines, said John Boudreaux, director of Assumption Parish Homeland Security and Emergency Preparedness.
The four pipeline companies were still depressurizing the lines as of Sunday afternoon, Assumption Parish Sheriff Mike Waguespack said.
“If all goes well, we’re hoping to get it (La. 70) opened at midnight,” Waguespack said.
The pipelines, which hold about 350 pounds per-square-inch each, are being depressurized at a rate of about 25 pounds per-square-inch per hour, Boudreaux said.
Boudreaux has said the decision to close La. 70 was necessary because the pipeline crosses under the highway just east of Bayou Corne. The compromised section of pipeline stretches about 400 feet in length about a half-mile south of the highway.
Of the three other pipelines being depressurized, two are owned by Acadian Gas, and one is owned by Florida Natural Gas, Waguespack said.
The sinkhole, which emerged overnight Thursday, toppled trees and turned forested patches of swamp into a watery mud flat, parish officials have said.
Authorities flew over the slurry around 9 a.m. Sunday and did not see an increase in the slurry’s area, Boudreaux said.
Louisiana Department of Natural Resources officials have said they believe a potentially failed salt cavern well owned by Texas Brine Co. LLC of Houston could be the cause of the sinkhole, as well as the cause of natural gas releases that have bubbled to the surface in Bayou Corne and Grand Bayou for more than two months.
Gov. Bobby Jindal declared a statewide emergency Friday and the state Office of Conservation issued its own emergency order Friday, directing Texas Brine to evaluate the cavern.
An evacuation of the area ordered Friday is still in place. While shelters are still open, residents are not being forced to leave, Boudreaux said.
The slurry area is on Texas Brine’s 40-acre facility on the south side of La. 70.