DC CLEAN RIVERS - POTOMAC RIVER TUNNEL PROJECT

DC Water will implement temporary traffic lane closures, trail detours, and parking restrictions on K Street Northwest between Potomac Street Northwest and 33rd Street Northwest as part of the Potomac River Tunnel Project. Crews will begin identifying underground utilities during the week of January 13, 2025, and expect to continue for approximately 3-4 weeks. These temporary closures will enhance the safety of pedestrians, bicyclists, motorists, and workers during the investigation process.

The contractor will use the potholing method to investigate the locations of underground utilities in preparation for constructing the Potomac River Tunnel (PRT). DC Water will construct a diversion facility at this site, including a diversion chamber, an approach channel, a drop shaft, and other structures to direct the flows from the existing combined sewer overflows (CSO) into the tunnel.

Work is estimated to take 3-4 weeks, pending inclement weather. Detours will be in effect until the investigation work is finished. The site will be restored when the work is completed. The map below highlights the detours, parking restrictions, and potholing locations.

Map: Work zone on K Street, NW between 33rd and Potomac streets NW

K Street Northwest Work Details (Map)

• Time: Monday – Friday from 9:30 am – 3:30 pm.
• Location: 3300 block of K Street, NW and Capital Crescent Trail.
• A flagger will assist pedestrians, bicyclists, and motorists around the work zone.
• Traffic Pattern Changes and Pedestrian Detours:
  • Portions of a travel/trail lane along K Street Northwest will be temporarily closed. Trail access for pedestrians and bicyclists will be shifted during construction.
  • Parking will be restricted on K Street Northwest near work zones as noted by the purple markings on the map.
  • See the map for specific details.

Important Information 

• Commuters and pedestrians are advised to follow signage and flagging personnel directing them through the temporary closures.
• Please plan your travel routes accordingly and anticipate 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 the DC Clean Rivers Project. The project consists of a large-diameter deep sewer tunnel, diversion facilities, drop shafts, and support structures to capture flows from existing CSOs along the Potomac River and convey them to the Blue Plains Advanced Wastewater Treatment Plant. The project is needed to reduce CSOs that contribute to water quality impairment of the Potomac River and ultimately the Chesapeake Bay; and to comply 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.

CSO outfalls release overflows into the Potomac River when rainfall exceeds the system’s capacity. This impacts water quality by increasing bacteria levels, contributing to low dissolved oxygen impacting aquatic life, and releasing trash into waterways. An estimated 654 million gallons of CSOs currently enter the Potomac River in a year of average rainfall. The proposed controls are estimated to reduce the volume of CSOs to the Potomac River by 93% and reduce their frequency from approximately 74 events to four events in a year of average rainfall.

For more information 

Project Email: dcpotomacrivertunnel@dcwater.com 
Project Website: dcwater.com/prt
Project Hotline: 202-972-1388
DC Water 24-hour Emergency: 202-612-3400