The no-swimming advisory at the town beach and Thurston’s Cove has been lifted. As of Oct. 2, people and pets are allowed to swim for the first time since Aug. 20. The ban was lifted by the Board of Health after two consecutive tests, done about a week apart, showed acceptable levels of cyanobacteria and did not detect cyanotoxins.
According to state and local standards, swimming should be banned when cyanobacteria levels exceed 70,000 cells per milliliter. Weekly testing started Aug. 3 and yielded a result of less than 50,000 cells/mL. Two weeks later it rose to 205,000 cells/mL, peaked at 371,000 cells/mL on Aug. 31, and remained at unacceptable levels until Sept. 21, when levels tested at 1,800 cells/mL at the town beach, and at 2,700 at Thurston’s Cove. Testing on Sept. 30 confirmed the water was safe for swimming.
Between mid-September and now, cyanotoxins were tested for three times, and were not not detected in any of the water samples.
