WSSC Water has detected high concentrations of blue-green algae, known as Harmful Algal Blooms (HAB), in the Triadelphia Reservoir. These blooms pose potential health risks to humans and animals. The reservoir, located along the Patuxent River in Montgomery and Howard counties, provides drinking water and is a popular spot for hiking, fishing, and boating.
The health advisory applies only to the Triadelphia Reservoir, while the neighboring T. Howard Duckett Reservoir remains unaffected. WSSC Water assures residents that drinking water meets Safe Drinking Water Act standards. As a precaution, the agency is actively monitoring water quality at the Patuxent Water Filtration Plant.
Recreational areas at the reservoir remain open, with the following guidelines in place:
- Boating and fishing are allowed, but rinse any body part that touches the water with clean drinking water afterward.
- Wash fish fillets thoroughly, and avoid consuming fish livers or other organs.
- Keep pets from swimming in or drinking the reservoir water, as required by WSSC Water regulations.
If you, your pet, or someone you know comes into contact with or ingested water at the reservoir, call Montgomery County health department at 240-777-0311.
WSSC Water will continue weekly monitoring of water quality and will post updates at wsscwater.com once the advisory is lifted.
For more details on algal blooms, visit WSSC Water’s Algal Blooms page.
