Pumping of raw sewage to river halted after pipe repairs

The New Orleans Sewerage & Water Board stopped pumping raw sewage into the Mississippi River on Friday after completing repairs to a 60-year-old, 60-inch sewer force main in the St. Roch neighborhood.

A bypass line was being used temporarily to pump the sewage to the river to avoid backups into homes and businesses or leakage from the pipe break. Sewage is again being routed through the Station D Sewer Force Main at 2800 Florida Avenue on its way to treatment at the Eastbank Wastewater Treatment Plant.

The 36-day repair job was complicated by a second break in the main, discovered after the first break was repaired. Workers had to excavate a pit about 15 feet deep beneath the pipe breaks, and install 25-foot sheet piles as shoring, before metal patches were soldered over the holes on the pipe's bottom.

SWB officials said about 150 cubic feet per second of wastewater was being released into the river during the pipe repairs, where it mixed with the river flow of about 260,000 feet per second, which is lower than normal this year. Officials with St. Bernard and Plaquemines parish water departments downstream have reported no contamination of their water.

The Friday completion of repairs was about eight days ahead of schedule. The site was monitored over the weekend to make sure no additional breaks had occurred.

"As we've said, this sewer force main is over 60 years old. Due to the age of the pipe, we faced additional leaks after the initial repair," said Ghassan Korban, executive director of the SWB. "Our crews worked dilegently and expeditiously to repair the sewer force main ahead of schedule."

The stretch of pipe that failed was in a vertical bend of the pipe system and included a number of connections to other pipes, and its replacement would require waiting for a customized pipe to be manufactured, so the temporary repairs were authorized.

A longer segment of pipe that includes the repaired piece is scheduled to be replaced within the next 18 months.

As part of that project, a separate bypass pipe will be installed that will deliver sewage to adjacent parts of the system leading to the treatment plant, and will not require disposal of sewage in the river.

his work is supported with a grant funded by the Walton Family Foundation and administered by the Society of Environmental Journalists.

Email Mark Schleifstein at [email protected] or follow him on Twitter, @MSchleifstein.