The Potomac Riverkeeper Network says its recent testing of an unnamed tributary found E. coli levels at more than 100 times the safe limit.
The Potomac Riverkeeper Network says sewage carrying dangerous levels of E. coli is leaking from a C&O Canal bypass system established during emergency repairs of the collapsed Potomac Interceptor sewer line.
Betsy Nicholas, the president of the group, said its recent testing of an unnamed Potomac River tributary passing through a nearby culvert found E. coli levels at more than 100 times the safe limit.
Soon after the Jan. 19 collapse, which spilled more than 240 million of gallons of sewage into the Potomac, D.C. Water set up a bypass system to divert wastewater around the rupture.
The bypass carries sewage into a short stretch of the C&O Canal between Locks 10 and 11, and directly above the historic Rock Run culvert.
“It’s just sort of this old brick tunnel,” said Nicholas.
Potomac Riverkeeper testers, as detailed in a new report, said they saw “clear evidence of dripping from the ceiling” as they collected samples over a two-week period.
The streamwater below contained E. coli at more than 100 times the EPA safety limit.
“It’s not the kind of kind of volume that we saw in the rupture — it’s a very low volume, but it is a very high bacteria level in a low volume of water,” said Nicholas. “In any event it’s still bacteria that could be very dangerous for human contact.”
Nicholas said Montgomery County’s ongoing advisory against coming into contact with the Potomac River remains in effect, “so that covers the area of this site.” The Potomac Interceptor collapse was just inside the Beltway along the Clara Barton Parkway.
The Potomac Riverkeeper Network, which states its mission is: “To protect the right to clean water for all communities and all those who live in and rely upon the Potomac and Shenandoah watersheds by stopping pollution, making drinking water safe, protecting healthy river habitats, and enhancing use and enjoyment for all,” wants the culvert to be addressed during D.C. Water’s emergency repairs.
“If they completed the remediation and never fix this problem, there would be ongoing leaking of bacteria into the river,” said Nicholas.
In a statement, D.C. Water said it is aware of the testing conducted by the Potomac Riverkeeper Network: “We are actively investigating the impact of the bypass on the culvert and adjacent tributary, while ongoing mitigation efforts have been underway.”
The water company said since the bypass was activated on Jan. 24, it has prevented over one billion gallons of wastewater from reaching the Potomac River.
D.C. Water also said it is nearing completion of its emergency repairs of the collapsed section, which will allow the bypass to be removed.
“Once the flow of the Potomac Interceptor is restored, environmental rehabilitation of all impacted areas will begin,” D.C. Water said. “This includes the C&O Canal.”
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