RIDOH and DEM Recommend Lifting Restrictions for Blue-Green Algae in Melville Ponds and Carbuncle Pond Published on Tuesday, November 28, 2023 The Rhode Island Department of Health (RIDOH) and the Rhode Island Department of Environmental Management (DEM) recommend lifting the advisory restricting recreational activities at Upper and Lower Melville Ponds in Portsmouth and Carbuncle Pond in Coventry. The advisories were related to high levels of blue-green algae, also known as cyanobacteria. Recent consecutive surveys and sample analysis confirmed that blue-green algae have been present but at acceptably low levels and that cyanotoxin is not present in detectable concentrations. These findings meet the advisory guidelines and support lifting the advisory. Blue-green algae conditions can change quickly, and it is possible that blooms may affect other water bodies in Rhode Island. The public should avoid contact with any body of water that is bright green or has a dense, floating algal mat on the water's surface. Blue-green algae blooms may look like green paint or thick pea soup. Toxins may persist in the water after a blue-green algae bloom is no longer visible. To report suspected blue-green algae blooms, contact RIDEM's Office of Water Resources at 222-4700 or DEM.OWRCyano@dem.ri.gov