Spring Cleaning in the Region’s Drinking Water System

March 11, 2014

From March 17 through April 28, 2014, the disinfectant in drinking water will temporarily switch from chloramine to chlorine.

The annual switch in water disinfection is part of a routine program to clean and maintain drinking water systems in the District of Columbia, Arlington County and the northeastern portion of Fairfax County. During the temporary switch to chlorine, local water authorities will also conduct system-wide flushing to enhance water quality. This program is a common practice for many U.S. water systems that use chloramine during the majority of the year.

The Washington Aqueduct is the organization responsible for treating and disinfecting drinking water for its wholesale customers: DC Water, Arlington County, and Fairfax Water. Local water authorities are responsible for monitoring drinking water to ensure chlorine levels continue to meet safe target levels.

Individuals and business owners who take special precautions to remove chloramine from tap water, such as dialysis centers, medical facilities and aquatic pet owners, should continue to take the same precautions during the temporary switch to chlorine. Most methods for removing chloramine from tap water are effective in removing chlorine. Individuals with special health concerns should consult a health care provider on the use of tap water.

During this time, individuals may notice a slight change in the taste and smell of their drinking water. Local water authorities recommend running the cold water tap for approximately two minutes and refrigerating tap water to reduce the chlorine taste and odor. Water filters are also effective for reducing chlorine taste and odor. For more information, please see Frequently Asked Questions (link below) or contact the appropriate water authority.

DC Water: 202-612-3440 (Monday-Friday, 8:00 a.m. - 4:30 p.m.) or 202-612-3400 (24-hour)

Arlington County: 703-228-6570 (Monday-Friday, 8:00 a.m. - 5:00 p.m.) or 703-228-6555 (24-hour)

Fairfax Water: 703-698-5800 (Monday-Friday, 8:00 a.m. - 6:00 p.m.) or 703-698-5613 (24-hour)

Washington Aqueduct: 202-764-0008 (Monday-Friday, 8:30 a.m. - 5:00 p.m.)

Latest News

Pennyfield Lock Potomac Interceptor bypass pipeline running next to C & O Canal with equipment

There is no active spill or overflow. Work to strengthen the pipe to begin soon.

Today, DC Water completed construction on a temporary bypass system as part of sewer repairs on the Potomac Interceptor near Pennyfield Lock in Potomac, Maryland. Crews turned on the pumps and successfully tested the system. With the bypass now ready, it will allow us to begin the emergency repairs inside the pipe by carrying the wastewater around the repair area.

DC Water Officials with NPS and ANC commissioners doing ceremonial groundbreaking

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.

Photo of the drop shaft looking from above down into the bottom

Starting the week of July 13, 2026, people who live, work or travel near the Canal Road NW entrance to Georgetown University may hear controlled blasting. This work is part of our Potomac River Tunnel Project.

When blasting happens, neighbors may hear a brief noise or feel light shaking. Drivers, cyclists, and pedestrians on Canal Road NW may also be stopped for a few minutes while we safely complete each blast.

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.

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Five photos from the American Water Works Association (AWWA) ACE26 conference featuring panel discussions, technical presentations, networking, and attendees posing at the ACE26 display.
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Upcoming Meeting
Date
July 13, 2026
Monday, 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.