Beginning the week of April 21, 2025, DC Water will implement temporary traffic lane closures near Georgetown University’s Canal Road Northwest entrance to identify and mark underground utilities for the Potomac River Tunnel Project. The work is expected to take 3-5 weeks to complete, depending on weather conditions.  

To minimize disruptions to campus traffic, excavation activities will be scheduled during non-peak hours, between 9:30 a.m. and 3:30 p.m. Most of the work will occur in the wooded area near the entrance, helping to reduce the impact on motorists and pedestrians. The process, known as potholing, involves excavating small holes to locate underground utilities, including water, electricity, gas, and fiber optics, in preparation for construction. 

While the utility investigation is underway, motorists and pedestrians are advised to follow directional signage and detours. Flaggers will direct traffic around the work zone. The site will be restored once the work is completed.  

Next year, DC Water will begin constructing a facility to divert excess sewage and stormwater to the Potomac River Tunnel, which will convey the overflow to the Blue Plains Advanced Wastewater Treatment Plant. 

Georgetown University, Canal Road Entrance (Maps A & B)   

• Start Date: Week of April 21, 2025, weather permitting 
• Time: Monday–Friday from 9:30 a.m. – 3:30 p.m.
• Location: West Road near the Canal Road Northwest campus entrance
• Traffic Pattern Changes and Pedestrian/Bicycle Detours: 
  • Traffic: Temporary lane closure during non-peak hours      
  • Pedestrian Detours: Pedestrians and bicyclists will be redirected around the work zone 
  • Please adhere to flagger directions and construction signage

Important Information  

• Be aware of road signs and flagging personnel directing traffic through the temporary closures.
• Please plan your travel routes accordingly and anticipate potential delays. Traffic control measures will be in place to guide motorists safely through the area. 

Project Details 

The Potomac River Tunnel is the next major phase of DC Water’s Clean Rivers Project. The tunnel will capture and divert the combined sewer and stormwater overflows to the Blue Plains Advanced Wastewater Treatment Plant. When the system exceeds capacity, 654 million gallons of untreated wastewater are released into the Potomac in an average year of rainfall. This increases bacteria levels, impacts aquatic life, and releases trash, polluting the Potomac and, ultimately, Chesapeake Bay. 

The tunnel is expected to begin operation in 2030 and will reduce the volume of overflows by 93% and the number of events from 74 to four in an average year of rainfall. The tunnel also ensures compliance with the 2005 Federal Consent Decree entered by DC Water, the District of Columbia, the US Environmental Protection Agency, and the US Department of Justice, as amended in January 2016. 

For more information  

Project Email: dcpotomacrivertunnel@dcwater.com  

Project Website: www.dcwater.com/prt 

Project Hotline: 202-972-1388  

DC Water 24-hour Emergency: 202-612-3400