The Potomac River received some unwelcome waste after a sewer main near Oxon Hill, Maryland sprung a leak.
TheBayNet.com reports that last month, residents of Oxon Hill were advised to avoid certain parts along the Potomac as repair crews were hard at work stopping the leak. Workers from the Washington Suburban Sanitary Commission (WSSC) faced an especially challenging job considering that fixing a sewer main involves building tributary pipes to divert the sewage.
“Fixing a broken sewer main is very different than fixing a broken water main,” said Lyn Riggins, a spokeswoman for WSSC. “You can’t just shut off the wastewater. The wastewater has to keep flowing or it will back up somewhere.”
The leak itself comes from a 14-inch crack in the main sewer line. The line was buried roughly two feet underground. In order to prevent back up, the repair crews built a temporary 7,000-foot pipeline to safely re-route the sewage around the cracked pipe. They also inspected the busted pipeline with a camera before they actually touched it.
Because the pipes were buried underground, they were prime candidates for the trenchless pipe repair method. As the name suggests, the method does not require digging large trenches in order to reach the pipes. Rather, the method calls for the use of existing pipes in order to guide special flexible pipes in them. Already available for residential projects for the past 10-15 years (although still relatively unknown), the trenchless method is considered more efficient and considerably less destructive than traditional methods.
All in all, the repair work took about a week to complete. More than 15,000 gallons of sewage was spilled before the work was done.
WSSC maintains that the leak could have been a lot worse had Oxon Hill not been located in a low-lying area. Due to the town’s topography, much of the sewage was effectively blocked off from the Potomac. Some of it, however, managed to seep into the river through the Oxon Run tributary.
WSSC and Oxon Hill officials reassured residents that their water was safe to drink since the sewage and wastewater treatment plants that treat the nearly water is separate from the drinking water plant. Still, officials warned residents to avoid certain areas close to the spillage and put up warning signs just in case.
“Even though there is waste water leaking in this area, the drinking water system is safe,” Riggins said.