"When determining if a beach is safe for swimming, local health departments and state officials measure levels of the bacteria enterococcus, which typically makes its way into marine water through fecal matter. High levels of enterococci in ocean water are a red flag that the water may also contain other disease-inducing microbes, which is why it is referred to as an “indicator” bacteria.Continue reading the article online (subscription may be required)
This is why beaches are often closed after heavy rainstorms — rain that isn’t absorbed into the soil or diverted can pick up fecal matter from pets and wild animals and flow it into the ocean.
“Stormwater is a major culprit for beach closures related to fecal bacteria,” said Bethany Traverse, coordinator of the Barnstable County Department of Health and Environment’s beach water testing program. “In any populated area, you have roadways and other infrastructure that affect the flow of contaminated water into the surrounding water bodies. When it rains, a lot of water is diverted into storm drains and away from bathing areas. But it’s not perfect; bird and animal waste will make its way into the water and storm water helps it get there in a rapid ‘flush.’”
The full Environment America report
|More than half of the thousands of beach sites sampled for bacteria across the country were potentially unsafe for swimming on at least one day in 2018|