Oak Bluffs health officials closed Medeiros Cove, near the Sailing Camp Park on Lagoon Pond, to swimming Wednesday, after water tests show more than the allowed amount of harmful bacteria in the water.
The pond at Lucy Vincent Beach in Chilmark and Uncle Seth’s Pond in West Tisbury remain closed this week.
Water samples taken at Medeiros Cove on Monday, August 6, showed 1,401 colony forming units per 100 milliliters (cfu/100ml) of enterococci bacteria. State regulators require beaches closed if the level exceeds 104 cfu/100ml.
“Monday, we tested,” Oak Bluffs health agent Shirley Feauteux said. “We had that really strong rain event. According to the state, we still have to close it.”
Medeiros Cove must remain closed to swimmers until further water testing indicates the bacteria levels do not exceed the limits.
All other beaches in Oak Bluffs including the beach near the Lagoon Pond Drawbridge, tested safe and remain open.
Water samples taken on Monday, August 2, from the pond at Lucy Vincent Beach show enterococci bacteria at 2,014 cfu/100ml, nearly 20 times the amount considered safe by state regulators. Water taken from the ocean off Lucy Vincent Beach, and from the ocean off the Chilmark Pond Preserve, sites on either side of the pond, tested below allowable limits.
Seth’s Pond, a freshwater pond on Lambert’s Cove Road in West Tisbury, has been closed for most of the summer, and it remains closed this week.
The Bureau of Environmental Health (BEH) posts beach water quality information on the Massachusetts Public Health Department website.
Enterococci are a group of bacterial species within the streptococcus genus, some of which (e.g. streptococcus faecalis) are typically found in human and animal intestines and are therefore present in sewage. These tests are also referred to as indicator organisms.
Any sample with a count greater than 104 cfu/100 ml qualifies as an exceedence, which requires that the beach be closed.
The BEH advises that swimming in polluted water can cause gastrointestinal symptoms such as nausea, vomiting, diarrhea, and abdominal pain, respiratory symptoms such as sore throat, cough, runny nose, and sneezing, eye and ear symptoms including irritation, earache, and itchiness, dermatological symptoms like skin rash and itching, and flu-like symptoms such as fever and chills.
Most of these symptoms are minor most of the time, but they can occasionally be more serious, especially in sensitive populations, like immuno-compromised children and the elderly.