Annual Spring Cleaning for Arlington Water Pipes Starts March 23

As performed each spring, Arlington County, the District of Columbia and northeastern Fairfax will adjust their water treatment process to allow for safe, controlled maintenance of the tap water pipe network.  

From March 23 through May 4, 2026, the year-round disinfectant chloramine will be temporarily switched to chlorine for most Arlington pipes to clean water mains and free them from any flow issues. For Arlington pipes located in the Willston Pressure Zone, serviced by Fairfax Water, the disinfectant switch will go from March 23 through May 26. 

Water service will continue uninterrupted during the procedure. Customers may notice a slight change in taste or scent when using the tap; this is to be expected, and the water is still safe to drink thanks to the purification process. County staff will continually monitor chlorine levels to ensure Arlington’s water meets all required federal and state standards. 

Arlington and neighboring jurisdictions receive water from the Washington Aqueduct, operated by the U.S. Army Corps of Engineers. The Aqueduct initiates the annual disinfectant swap as a standard water treatment practice.  

Arlington County’s water remains safe to use and is not impacted by the recent DC Water sewage spill in the Potomac River. The primary water intake to the Dalecarlia Water Treatment Plant (located near Great Falls) is upstream of the location of the spill and therefore unaffected. 

Along with the disinfectant switch, Arlington will conduct a system-wide flushing to enhance year-round water quality. Residents may see open fire hydrants as part of the practice. A map of hydrant flushing locations will be available soon at water.arlingtonva.us.  

What to expect between March 23 and May 4

• Water from the tap may have a distinct smell and taste of chlorine. These can be minimized by using a tap filter system or letting the water sit in an open container for an hour or two in the refrigerator, which will allow the chlorine smell and taste to dissipate. 

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

• Due to the presence of sediment, there is a possibility that discolored water generated from the flushing of fire hydrants may stain clothes being washed in nearby homes. Flushing will take place between 9 a.m.-3 p.m., Monday-Friday. Residents are encouraged to plan ahead regarding doing laundry during this time frame.  

The County can provide a special detergent to remove related stains upon request. Call 703-228-5000 for more details. 

Arlington’s water distribution network is made up of some 500 miles of pipes linked to homes, businesses and schools. The County’s drinking water continues to meet or exceed all safety standards established by the federal Environmental Protection Agency and Virginia Department of Health. 

For more information on Arlington’s water treatment process, visit the County website or call 703-228-5000, Monday-Friday, 7 a.m. to 7 p.m. or the 24-hour line at 703-228-6555.