The District of Columbia, Arlington County and northeastern Fairfax County will clean out their tap water network starting Monday—a safe, annual process. Water service continues uninterrupted during the process, which runs from April 5 through May 17. During that time, drinking water may smell or taste slightly different. 

The U.S. Army Corps of Engineers’ Washington Aqueduct, water supplier to these regions, performs the temporary disinfectant switch from chloramine to chlorine to allow local water authorities to clean the pipes and maintain water flow. Washington Aqueduct continues to add a corrosion inhibitor during the process to reduce the potential for release of lead in service lines.

Local water authorities will continually monitor the drinking water for safe chlorine levels as well as conduct system-wide flushing to enhance water quality. At the same time, water utilities will systematically flush fire hydrants by opening them up to allow fresh water to flow through the system. Crews operating hydrants in this manner are a normal part of this routine. This process is repeated nearly every spring, in this region and across the nation.

This temporary cleaning often adds a new smell or taste to tap water. If customers opt, they can run the cold water tap for about two minutes, then use a water filter or allow water to sit in a container in the refrigerator to remove chlorine taste and odor.

Customers who take special precautions to remove chloramine from tap water should continue such methods during the temporary switch to chlorine. As always, those with special concerns should consult their health care provider.

Washington Aqueduct is the wholesale water supplier for the District of Columbia, Arlington and northeastern Fairfax County.

For more information, please contact the appropriate water authority:

• DC Water: dcwater.com/chlorine-switch; 202-612-3440 (Monday-Friday, 8:00 a.m. - 4:30 p.m.) or 202-612-3400 (24-hour)
• Arlington County: 703-228-5000 (Monday-Friday, 7:00 a.m. - 7:00 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)