D.C., Fairfax County and Arlington County are taking part in the annual process of flushing and disinfecting the region’s water mains.
Beginning Monday, residents may notice a slight change in the odor or taste of their tap water as chlorine is added to disinfect and clear away bacteria and natural biofilm buildup. Officials said the water remains safe to drink and the change shouldn’t last more than a week.
In the District, D.C. Water said the Washington Aqueduct, which is operated by the U.S. Army Corps of Engineers, performs this annual disinfectant switch as part of routine maintenance to support overall water quality.
There are ways to mitigate the taste and smell of tap water if it becomes an issue. Faucet and pitcher filters can help. You can also leave an open container of water in the refrigerator for up to two hours before drinking it, which allows the chlorine to dissipate.
Crews will open fire hydrants across all three jurisdictions for short periods of time to help move fresh water through the system. The flushing process can result in discoloration or sediment buildup in tap water. Fairfax Water said these conditions are not harmful and are typically short-lived.
While officials said that water remains safe to drink, they warn it could stain clothing if used for laundry.
In Arlington County, Virginia, officials said flushing will take place through May 4 between 9 a.m. and 3 p.m., Monday through Friday. Residents are encouraged to plan ahead if they need to do laundry while the water is being treated.
Arlington residents can request a special detergent that removes stains caused by the water, by calling the county at 703-228-5000 for more details.
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