DC Water: Rain will help rinse C&O Canal, now that sewage flow is restored to Potomac Interceptor

Monday’s expected heavy rain should be beneficial to the environmental cleanup at the site of repairs to the sewage line that collapsed on Jan. 19, along the Clara Barton Parkway, according to D.C. Water.

Over the weekend, D.C. Water completed emergency repairs to the collapsed Potomac Interceptor, so wastewater is again flowing the length of the regional pipeline from Loudoun County to the Blue Plains Advanced Wastewater Treatment Plant in Southwest, D.C.

With the flow of sewage contained within the Interceptor, D.C. Water has turned off pumps that were diverting sewage from the Interceptor into a short stretch of the C&O Canal to bypass the collapse site and then returning the wastewater to the pipe further downstream.

Crews have been vacuuming sludge from the canal, and D.C. Water said Monday’s expected rain will be helpful.

“The rain is expected to assist with cleaning the canal,” D.C. Water said in a statement. “While sections of the repaired pipe remain open, there is no danger expected from the rain. The pipe sections are contained in the trench boxes and the Interceptor has excess capacity for any additional flow caused by rain infiltration.”

A trench box is a safety structure, made of aluminum or steel, that allows crews to access a pipe that is being repaired within a trench.

For the longer-term environmental cleanup of the canal, D.C. Water said crews are finishing work on a freshwater dam at Lock 14, upstream from the collapse site, “which will be used to help flush out residual waste and contaminants in the C&O Canal.”

D.C. Water said work continues with the U.S. Army Corps of Engineers and Environmental Protection Agency on the environmental rehabilitation of the drainage channel, culvert and river shoreline impacted by the overflows.

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Neal Augenstein

Neal Augenstein has been a general assignment reporter with WTOP since 1997. He says he looks forward to coming to work every day, even though that means waking up at 3:30 a.m.

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