Taste and Odor Changes to Tap Water Still Affecting Many in Maryland

As previously reported, customers served by WSSC Water’s Potomac Water Filtration Plant (Potomac River) may still notice changes in the taste and odor of their tap water because of algal activity in the Potomac River (map available below). This change is not harmful and is due to an increase in a naturally occurring substance, Geosmin, caused by warmer weather and low water levels in the Potomac River.  As Geosmin are prone to fluctuate with rain and changing water levels, customers may notice order is stronger at certain times than others. This is completely normal.

The odors from the naturally occurring compound, Geosmin, are not toxic. Because the human nose can detect Geosmin concentrations at very low levels, the unpleasant smell can cause sensitive individuals to experience nausea/headaches. Despite the taste and odor issues, the water remains safe, meeting all EPA Safe Drinking Water Act standards.

WSSC Water frequently monitors levels of Geosmin at the plant and makes treatment updates accordingly to minimize the odor. Per WSSC, “We perform 500,000 laboratory tests on our water every year, on samples from both of our water filtration plants and from 90 different locations throughout our distribution system. If there were a reason to believe the safety of our water was compromised, we would immediately issue a public notification.  This would include web alerts, text messages*, news outlets and utilizing our social media platforms.

Boiling the water will not improve the odor. Flushing the water lines inside homes or flushing the WSSC Water mains in the impacted areas will not improve the taste and odor issues. Customers can always reach us (24/7) by calling the Emergency Call Center at 301-206-4002 or complete this form to report a water quality concern.