This week the Washington Aqueduct reverted back to chloramine from chlorine in the water treatment process for tap water provided to the District of Columbia and Arlington County and Falls Church City in Virginia.

The temporary disinfectant change, which began April 6, 2009 and ran through May 3, 2009, is a standard practice in the water utility industry. It is an annual process used to keep water mains clean and free of potentially harmful bacteria throughout the year.

Customers may continue to notice a chlorine taste and odor for an additional week as the chlorine eventually leaves the water distribution system. Customers may be able to reduce the taste by refrigerating a pitcher of drinking water overnight.

Users who take special precautions to remove chloramine from tap water such as dialysis centers, medical facilities or aquatic pet owners should take note of this change in the water treatment process and act accordingly. Users of tap water for home dialysis equipment and aquariums should also be aware of this change.

For additional water quality information or questions please contact the DC WASA Water Quality Division at 202-612-3440 (Monday-Friday, 8:00 a.m. – 4:30 p.m.) or call 202-612-3400 (24-hour).