Long-Term Rehabilitation Work on Potomac Interceptor Continues in Preparation for Construction

April 21, 2026
Photo of long stretch of C & O Canal with soil removed
  • DC Water has excavated a section of the Potomac Interceptor along Clara Barton Parkway, outside the I-495 Beltway as part of the accelerated rehabilitation of more than 2700 linear feet of the interceptor that was previously planned.
  • As part of the long-term rehabilitation project, crews are beginning to remove trees which is necessary to construct a bypass chamber that will divert wastewater around sections of the pipe while they are being rehabilitated.
  • Soil removal is now 55% complete in the C & O Canal. Work continues to remove the soil down to the clay liner on the remaining sections of the canal between locks 10 and 12.
  • Cleaning is complete on the historic canal’s locks 11, 12, and 13 utilizing NPS prescribed methods.

Water Quality Sampling

Daily water quality testing continues to show E. coli levels within the typical range for recreation, with normal historical fluctuations attributed to rain, heat, stormwater runoff, and other known environmental factors. See the District Department of Energy and Environment webpage for more details.

Ongoing sampling is precautionary and intended to address community concerns, ensuring the highest standards of public health and safety.

For the Potomac River, historical water quality data shows E. coli levels may vary from a range as low as 10 MPN/100mL to as much as 5,000 MPN/100mL on a given day.

Results April 13 – present below: (past results can be found here)

graphic of water quality sampling results

You can find more information about the environmental rehabilitation, get the latest news and information, and results of all the water quality testing on our Potomac Interceptor Response page.

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We hope to see you tonight for our upcoming Lead Free DC Virtual Meeting! We will discuss Losing the Lead Without Losing Your Yard. This session is an in-depth look at an important concern for many homeowners: how Lead Free DC restores your yard following a lead service line replacement.

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Hundreds of Sampling Results Confirm Return to Normal Bacteria Levels in Potomac River

DC Water has outlined its next steps to complete the environmental cleanup and its plan for continued water quality monitoring this summer, as part of the ongoing response to January’s failure in the Potomac Interceptor sewer pipeline. The plan, submitted to the Maryland Department of the Environment (MDE), is supported by extensive data from hundreds of samples.

crews removing soil in C & O Canal

Work continues to remove the remaining soil between locks 10 and 12 of the C & O Canal which was used as an emergency bypass while the Potomac Interceptor was repaired. Crews area also removing plants, trees, and shrubs in preparation for the long-term rehabilitation of the Potomac Interceptor.

Upcoming Meeting

Board of Directors Meeting

April 24, 2023

Monday 9:00 AM

Announcement

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Customer Service Center Announcement

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