UPDATE: Work to Remove Rocks and Debris Dam Blocking Damaged Potomac Interceptor Nearly Complete

February 25, 2026
Photo of remaining rocks and debris

Potomac Interceptor Repairs Update
February 25, 2026 

  • Crews are nearly done removing a rock and debris dam that was blocking the damaged section of the Potomac Interceptor. Several feet of rocks and debris remain to be cleared and is expected to be completed overnight. 
  • Since Monday, crews have cleared about 45 feet of rocks and debris. To do this, the excavation area was extended around the damaged pipe section to expose the pipe, cut the top off, and reach the debris dam.
  • No overflows have been reported entering the Potomac River in 17 days. The last release into the river occurred on February 8.  
  • Additional work is underway to clear soil, muck, and other debris in the upstream section of pipe around the collapse site.
  • Zeldin Visit with Gadis
    DC Water CEO David L. Gadis shows EPA Secretary Lee Zeldin the progress being made to repair the damaged section of the Potomac Interceptor.

    Once the rocks, muck, and debris are removed, work will begin to prepare the pipe for repair. To ensure the geopolymer – a material with similar strength to concrete and more resistant to sewer gases – can properly adhere the sewer pipe must be pressure washed and thoroughly cleaned out to eliminate any debris. 

  • Once the pipe is cleaned and prepared, the geopolymer will be sprayed on. This could begin as early as next week. The geopolymer will be applied in layers and will require time to cure before more layers are added to reach the desired thickness. 
  • Works is progressing and is on target to complete the emergency repairs by mid-March, restoring the full flow and functionality to the Potomac Interceptor and eliminating the need for the bypass pumping system that is currently using the C&O Canal to divert the flow around the collapsed section and back into the Potomac Interceptor further downstream.
  • Work is underway in coordination with the US Army Corps of Engineers on some environmental mitigations to divert stormwater runoff away from the creek bed and channel, to avoid carrying any residual wastewater or contaminates in the soil to the river. 
  • Teams are also on site, beginning initial preparations and marking the area to begin the environmental restoration process. 

DC Water is committed to protecting public health and the environment and completing emergency repairs as quickly and safely as possible and to restore the immediately impacted areas. 

Water Quality Sampling Results

DC Water is performing daily water quality sampling. It’s important to note that historically the E. coli levels in the Potomac and Anacostia rivers vary widely from day to day. This is reflected in recent sampling results with stormwater runoff from rain and snow impacting water quality. Fluctuations in water quality are influenced by factors such as weather events, river flow, runoff, pollutants, releases of combined overflows, and other sources discharging into waterways.

Given these variables, measurements taken much further downstream cannot be attributed solely to this incident.

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. A more detailed explanation is posted on the District Department of Energy and Environment (DOEE) website at doee.dc.gov/release/potomac-interceptor-update-and-faqs

Below are the results of sampling during the period from February 16 – present. Past results may be found on our dedicated Potomac Interceptor Response page.


   chart of water quality sampling results

For more information about the Potomac Interceptor Response go to dcwater.com/potomac-interceptor-collapse.

Latest News

Photo of soil removal and excavation

DC Water and its contractor have removed all the soil down to the clay liner between locks 12 and 13, marking 50% completion of the canal clean-up. Soil removal between Locks 13 and 14 was completed earlier this month. Meanwhile, clean-up efforts continue between locks 10 and 12, with sludge removal complete and soil removal now underway.

View of Mary at bottom of shaft inside tunnel shown from above

First turn of cutterhead signals the start of excavation for the Potomac River Tunnel Project

In a defining moment for one of the District’s largest infrastructure investments, DC Water has marked its next major milestone in the Potomac River Tunnel Project. The first tunnel boring machine, Mary, has launched her northbound journey breaking through the soil to signal the start of excavation.

With the first turn of Mary’s drill-like cutterhead underground, the machine pushed forward to begin tunneling, representing the transition from years of planning and preparation to active tunnel construction on the $819 million project.

Photo of the vegetation growing back in the culvert area
  • DC Water has completed soil removal, utilizing excavators and manual digging, to expose the clay lining for the C & O Canal between locks 13 and 14. This is the final step in the clean-up process ...

Upcoming Meeting

Board of Directors Meeting

April 24, 2023

Monday 9:00 AM

Announcement

View of Mary at bottom of shaft inside tunnel shown from above
DC Water Launches Tunnel Boring Machine Mary, Marking Important Step for Potomac River Tunnel Project

First turn of cutterhead signals the start of excavation for the Potomac River Tunnel Project

In a defining moment for one of the District’s largest infrastructure investments, DC Water has marked its next major milestone in the Potomac River Tunnel Project. The first tunnel boring machine, Mary, has launched her northbound journey breaking through the soil to signal the start of excavation.

With the first turn of Mary’s drill-like cutterhead underground, the machine pushed forward to begin tunneling, representing the transition from years of planning and preparation to active tunnel construction on the $819 million project.

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Upcoming Meeting
Date
April 15, 2026
Wednesday, 9:30 AM

Customer Service Center Announcement

Payment Plan Incentive: provides a credit back of 50% of the last 3 payments made. Eligible participants are residential customers who have had an outstanding balance for 60 days or greater and with an outstanding balance of $500 or more.