We know that our sewer mains are intact. There was no combustible gas detected in our sewer lines. We found high water in the Entergy vault, which was above our sewage level, preventing liquid waste we collect from flowing into the vault.
— SWB New Orleans (@SWBNewOrleans) February 19, 2020
The New Orleans Sewerage and Water Board on Feb. 19 concluded its end of the investigation into the cause of a sudden explosion on Dauphine Street last December, launching several manhole covers into the air and igniting a nearby car.
The explosion occurred at approximately 5 a.m. on Dec. 16 in the 500 block of Dauphine Street, near the intersection of Toulouse and Dauphine, according to the New Orleans Fire Department.
A video taken by an eyewitness was published by WWL-TV on Dec. 16 and shows the front end of a car on fire.
Video of fire on Dauphine @WWLTV courtesy of person evacuated pic.twitter.com/ZS8QT5q56p
— Duke Carter II (@dcarterII) December 16, 2019
Causes of the explosion include a sewer methane explosion to a faulty Entergy electrical line, according to city officials.
In coordination with Entergy, the SWB launched a process-of-elimination investigation into the explosion’s cause days later, said Executive Director Ghassan Korban.
During the investigation, the SWB learned that the sewer main lines were intact and contained no detectable amount of combustible gas, Korban said.
There was high water in the Entergy Vault, which was above the SWB’s sewage level, which prevented liquid waste collected by the SWB from flowing into the vault, Korban added.
Additionally, Korban said, the sewer line on St. Louis Street was cleaned and inspected, which found no breaks or intrusions.
“It is logical for the agency that owns the vault where the explosion occurred to be responsible for determining the root cause of the explosion,” Korban said. “In the interest of public safety, we stand ready to assist our partners as they continue to search for the cause.”