State health and environmental officials are advising residents to avoid all contact with Lower Melville Pond after confirming the presence of a harmful cyanobacteria bloom that can cause serious health problems in humans and pets.
The Rhode Island Department of Health and Rhode Island Department of Environmental Management issued the advisory Friday, warning that swimming, fishing, boating and kayaking pose high health risks at the Portsmouth pond.
Cyanobacteria, commonly called blue-green algae, occur naturally in water bodies but can form dangerous blooms under certain environmental conditions. These harmful algae blooms can produce toxins that cause skin and eye irritation, gastrointestinal illness and, in severe cases, liver and nervous system damage.
“People should not drink untreated water or eat fish from affected waterbodies,” the agencies stated in their advisory. Pet owners were specifically cautioned against allowing animals to drink or swim in the contaminated water.
The agencies emphasized that residents should use caution throughout Lower Melville Pond, as the algae blooms can shift locations within the water body.
Young children and pets face elevated risks because they are more likely to accidentally ingest water during recreational activities, according to health officials.
Symptoms of exposure can range from skin, nose, eye and throat irritation to more serious effects including stomach pain, diarrhea, vomiting, nausea, dizziness, headaches and fever. Officials advise anyone experiencing these symptoms after contact with the pond to consult their healthcare provider.
The contaminated water may appear bright to dark green with thick algae floating on the surface, resembling “green paint, pea soup, or green cottage cheese,” according to the advisory.
If exposure occurs, officials recommend immediately rinsing skin with clean water, showering and washing clothes upon returning home. Pet owners should wash exposed animals with clean water and prevent them from licking algae from their fur. Veterinary care should be sought if pets show signs of illness within 24 hours.
Residents can report suspected cyanobacteria blooms to the Department of Environmental Management’s Office of Water Resources at 401-222-4700 Press 6 or DEM.OWRCyano@dem.ri.gov. Photographs of suspected blooms are encouraged.
Current advisories and water quality data are available on DEM’s Freshwater Cyanobacteria Tracker Dashboard at www.dem.ri.gov/bluegreen.