EMERGENCY WATER MAIN BREAK
Jul 25, 2026 | 08:40 PM

EMERGENCY WATER MAIN BREAK
Jul 25, 2026 | 04:44 PM

CSO 021 Diversion Facilities Project

2017 0112 PR-B Project Photo

Overview

The CSO 021 Diversion Facilities projects consist of the construction of a structure to divert flows from the existing Combined Sewer Overflow (CSO) 021 outfall, the largest CSO on the Potomac River. In order to minimize future impacts, the project was constructed simultaneously alongside the ongoing Expansion Project at the John F. Kennedy Center for the Performing Arts. The diversion structure will ultimately be connected to the future Potomac River Tunnel, which will convey the diverted flows to the Blue Plains Advanced Wastewater Treatment Plant for treatment prior to discharge to the Potomac River.

Scope of work

  • Construction of a new diversion chamber to divert flow from the existing CSO 021 Outfall Sewer to the future Potomac River Tunnel
  • Construction of a shaft to drop captured flows to the future Potomac River Tunnel
  • Construction of a ventilation control facility to regulate airflow in the tunnel system
  • Coordination with the Kennedy Center Expansion Project to ensure compatibility of surface features (manhole openings, equipment pads, etc.) with site improvements and minimization of future impacts related to construction and commissioning of the future Potomac River Tunnel

Partners

DC Water worked closely with multiple stakeholders to provide timely information about the project, to solicit input, and to ease the burdens of construction. These stakeholders include the Kennedy Center, NPS, District Department of Transportation, and Department of Energy & Environment. DC Water also coordinated with the Advisory Neighborhood Commission to provide regular updates.

Project Location

Contact Information

Senior Public Outreach Officer: Hadiah Jordan (202) 787-4717

Email: dccleanrivers@dcwater.com

clean river
Clean Rivers

The Clean Rivers Project is DC Water's ongoing program to reduce combined sewer overflows into the District's waterways - the Anacostia and Potomac Rivers and Rock Creek. The Project is a massive infrastructure and support program designed to capture and clean water during heavy rainfalls before it ever reaches our rivers.

Upcoming Meeting

Board of Directors Meeting

April 24, 2023

Monday 9:00 AM

Announcement

DC Water Officials with NPS and ANC commissioners doing ceremonial groundbreaking
DC Water Breaks Ground on Piney Branch Tunnel, Final Phase of DC Clean Rivers Project

Today, DC Water broke ground on the Piney Branch Tunnel, the final major tunnel in our Clean Rivers Project. This work will help keep sewage and trash out of local waterways and make Rock Creek, the Potomac River, and the Chesapeake Bay cleaner for our community.

When we finish the Piney Branch Tunnel, it will hold at least 4.2 million gallons of rainwater and wastewater during heavy storms. Instead of overflowing into Piney Branch, that water will go to the Blue Plains Water Resource Recovery Facility, where it will be treated.

Latest Blog Post
Plastic bottles, cups and other floating debris on the surface of the Anacostia River before the Anacostia River Tunnel began operating.
Cleaner Waterways Start With Everyday Choices
Protecting our waterways starts with everyday actions and continues through critical infrastructure designed to keep pollution out of our rivers.
Upcoming Meeting
Date
July 28, 2026
Tuesday, 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.