EMERGENCY WATER OUTAGE
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EMERGENCY WATER OUTAGE
Jul 16, 2026 | 09:00 AM

EMERGENCY WATER OUTAGE
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Clean Rivers Project

DC Water’s Clean Rivers Project


Everything you need to know about the Clean Rivers Project and how it affects...

your water

your neighborhood

your rivers

your life

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

Clean Rivers Projects

The DC Clean Rivers Project will reduce CSOs in an average rainfall year by 96 percent system-wide. Reductions will be 98% for the Anacostia River, 93% for the Potomac River and 90% for Rock Creek. In addition, the Project will reduce the chance of flooding in chronically impacted areas in Northeast Boundary from approximately 50 percent to 7 percent (equivalent to a 15-year storm) in any given year and reduce nitrogen discharged to the Chesapeake Bay by approximately 1 million pounds per year.

Green Infrastructure Banner

Green Infrastructure

Green Technologies for the District

Piney Branch Tunnel

Piney Branch Tunnel

Storing overflows from CSO 049

PRT Tunnel Map

Potomac River Tunnel Project

CSO Relief for Potomac River

Just the facts
96 %
Reduction
System-wide CSO volume
98
%
Reduction
CSO Volume to the anacostia river
92
IMPERVIOUS ACRES
OF LAND MANAGED WITH GREEN INFRASTRUCTURE AT ROCK CREEK
15
YEAR STORM CONVEYANCE
FOR CHRONIC FLOOD AREAS SERVED BY NORTHEAST BOUNDARY TUNNEL
1
Million
POUNDS
REDUCTION OF NITROGEN TO CHESAPEAKE BAY
18
Miles
OF TUNNELS
OVER 100 FT BELOW GROUND
Clean Rivers Project Map

What is the Clean Rivers Project ?

The Clean Rivers Project is comprised of a system of deep tunnels, sewers and diversion facilities to capture CSO's and deliver them to DC Water’s Blue Plains Advanced Wastewater Treatment Plant.  The Project is also installing Green Infrastructure to assist with the reduction of CSO's to the Potomac River and Rock Creek. The Anacostia River and Potomac River tunnel systems include more than 18 miles of tunnels that are larger than the Metro tunnels and are constructed more than 100 feet below the ground.

Combined Sewer Overflows
GI Tech graphic

What is Green Infrastructure?

DC Water’s Clean Rivers Project involves the construction of innovative green infrastructure technologies that include bioretention (rain gardens) in planter strips and curb extensions, permeable pavement on streets and alleys, and downspout disconnection (including rain barrels).  These practices will manage stormwater by taking advantage of the earth’s natural processes, such as allowing water to infiltrate into the soil, evaporate into the air, or for plants to use the water and expire it as vapor.

Green Infrastructure
Diversion Facility Graphic

What is the Tunnel System?

The Clean Rivers Project is installing "diversion facilities" at strategic locations to capture untreated sewage from wet weather events and convey it to the Blue Plains Advanced Wastewater Treatment Plant. Diversion facility components include a Diversion Chamber to intercept flow from the existing sewers, an Approach Channel to direct the flow and create a vortex, a Drop Shaft to drop the flow approximately 100 feet and an Adit to connect to the main tunnel system. The entire system works by gravity. During dry weather conditions, the existing sewer system uses its existing Dam and Interceptor system to deliver flow to Blue Plains for treatment.

Blue Plains

Do you have a question or comment?

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    202-787-4400

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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
Five photos from the American Water Works Association (AWWA) ACE26 conference featuring panel discussions, technical presentations, networking, and attendees posing at the ACE26 display.
ACE26 Highlights: How DC Water Advanced the Conversation on Water
More than 80 DC Water employees joined thousands of water professionals in Washington, D.C., sharing expertise, building partnerships and advancing conversations that will help shape the future of water.
Upcoming Meeting
Date
July 17, 2026
Friday, 2:00 PM

Upcoming Events

Jul 23
Jul 25

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.