Red, temporary fencing went up around a contaminated pond in Montgomery County, Maryland, as leaders warn you to stay out of nearby waterways.
County officials say your tap water is safe, but testing found elevated levels of PFAS in a stormwater pond and nearby streams near Great Seneca Highway and Key West Avenue in the Gaithersburg and Rockville area.
At the pond, across Great Seneca Highway near where Decoverly Drive crosses, crews are putting up the fencing to keep people and pets out.
The affected waterways run near Shady Grove Hospital along Great Seneca Highway and just past Muddy Branch Road.
PFAS are manmade chemicals often called “forever chemicals” because they do not break down and can build up over time in the environment and the body.
Jennifer Macedonia, director of the Montgomery County Department of Environmental Protection, said testing pointed to an area near a former county site, where firefighters trained for decades until 2015.
“The state’s testing detected high levels of PFAS in an area on and adjacent to the site of the county’s former public safety training facility,” Macedonia said.
Officials said the contamination may be tied to chemicals used in firefighting foam at that training facility.
The high readings came to light after WSSC Water requested more testing in the Muddy Branch area. WSSC Water PFAS Program Manager Laura O’Donnell said despite the findings in the pond and stream, the drinking water in the area remains safe.
“I want our WSSC Water customers in Montgomery and Prince George’s counties to know that the water we provide is safe. This is not a public water supply issue,” O’Donnell said.
Montgomery County Executive Marc Elrich said the county is working to respond and protect the public.
“The county is taking this issue and the concern very seriously, and it’s taking steps to inform the public and protect public health and the environment,” Elrich said.
The county filed a lawsuit in 2023 against companies that made PFAS, accusing them of hiding risks while profiting from the chemicals.
Elrich also noted the chemicals are widespread.
“This stuff is ubiquitous and it’s not always easy to figure out where it came from, but it’s there now,” Elrich said.
Health officer Dr. Kisha Davis said the greatest risk comes from repeated exposure over time.
“The health risks are tied to chronic exposure, meaning drinking contaminated water or eating contaminated fish every day for years, which allows the chemical to gradually accumulate in the body’s tissues,” Davis said.
She added that brief contact is less concerning.
“I don’t think that folks need to worry too much about if they were playing in that stream over the weekend,” Davis said.
For nearby homeowners with private wells, the county said it’s reaching out directly and offering free testing to make sure their drinking water is not affected.
Out of caution, the county is advising residents to stay out of the affected waterways, keep pets away and avoid eating fish caught there.
Officials said additional testing is underway to determine how far the contamination may extend.
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