MANCHESTER — Swimming was banned at a Manchester beach and remained so at an Essex beach on Tuesday due to high bacteria counts.
The town portion of Gray Beach, located off Raymond Street in Manchester, failed weekly water testing for enterococci bacteria, which can cause infections. The beach is temporarily closed to swimming, the town announced Tuesday shortly before 4:30 p.m.
The tests showed 186 colony-forming units (CFUs) — or living individuals —of enterococci within 100 milliliters of water, where the state limit for bathing beaches is 104 CFUs.
"We will reopen this portion of beach when retesting provides a negative result," the notice said. The beach was retested Tuesday, and if results are positive, could open later this week.
Much of Gray Beach, also known as Magnolia Beach, is privately owned by the Manchester Bath and Tennis Club, and testing there showed enterococci under state limits for swimming.
Manchester's five other beaches — Singing, West Manchester or Black Cove, Black, White, and Tuck's Point, also passed. All the town's beaches are tested for enterococci weekly, from mid-May through Labor Day.
Meanwhile, Chebacco Lake at Centennial Grove in Essex remains closed to swimmers after a toxic algae bloom of cyanobacteria was discovered there late last week.
Health concerns associated with cyanobacteria blooms vary depending on the type of cyanobacteria, the route of exposure, and the amount of cyanotoxins present, the Essex health board said. Ingestion is the primary concern since ingesting small amounts of cyanobacteria or cyanotoxin can cause gastrointestinal symptoms while larger amounts may cause liver or neurological damage.