• With 32 days of no overflows reaching the Potomac River, DC Water and its contractor continue to make progress on the Environmental Rehabilitation of the areas impacted by the failure in the Potomac Interceptor.
• In Area 1, which is divided into two sections from the collapse site to the length of the drainage channel along Clara Barton Parkway, DC Water crews have completed about 70% of the initial phase of rehabilitation on the west section.
• Additional rehabilitation work continues on the east side of Area 1 and in Area 2 around the Rock Run culvert down to the tributary, working in coordination with the Environmental Protection Agency and US Army Corps of Engineers.
• The first phase of the clean-up includes brush and debris removal, mucking, soil raking and soil removal, and assessment.
• Work remains on target to complete the emergency repair by mid-March to return full flow to the interceptor. This process will involve carefully removing the bulkhead gate blocking the flow, while methodically turning pumps off as more flow is introduced to the pipe.
• Once all the pumps are turned off and flow returned to the interceptor, the C & O Canal will no longer be needed for the bypass system. The remaining wastewater will continue to drain into the Potomac Interceptor downstream of the collapse site, and any residual wastewater will be pumped out of the canal to allow the environmental rehabilitation to begin.
• The emergency repair is now focused on applying geopolymer to the trench boxes around the excavated pipe sections to provide a waterproof seal to successfully return the flow to the interceptor.
• The trench boxes will provide an “open flow channel” allowing the wastewater to flow through sections of the pipe where the crown has been removed. These openings will be used to insert new pipe sections into the existing pipe as part of the long-term rehabilitation that when complete will return it to like-new condition.

Water Quality Sampling Results

Fluctuations in water quality are influenced by factors such as rain, heat, or other 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.

As of March 4, two new sampling locations have been added at Sycamore Island and Lock 6. Sample results from March 2 - present. Past results may be found here.

For more information, including the latest news and updates, and to provide feedback on the Environmental Rehabilitation Plan go to our dedicated page for the Potomac Interceptor Repairs.