Lexy Porter samples water from Lake Michigan at Pere Marquette Beach in Muskegon for water quality testing. Photo by Valerie Wojciechowski, Grand Valley State University.
As air and water warm for summer, so do thoughts of beach time. Is it safe to get in the water?
“In Michigan, most of our beaches are doing well,” says Shannon Briggs, a toxicologist in the Water Resources Division of the Department of Environment, Great Lakes, and Energy (EGLE). “About 4% of all samples are elevated, meaning they exceed water quality standards [for full body contact]. Over the years, about 20 to 40 beaches report multiple exceedances. There are over 1,200 beaches in Michigan and about 400 are monitored.”
A relatively new tool is adding to the confidence of local health officers that they are capturing in a timely way indicators of water quality problems at public beaches. Using the QPCR method (quantitative polymerase chain reaction, which monitors the amplification of a targeted DNA molecule in real time), health departments can respond far more quickly in issuing advisories regarding potential threats at beaches in Michigan, often the same day samples are taken. The culture-based method for measuring the fecal bacteria E. coli, formerly the predominant method, takes a minimum of 18 hours to yield results, while QPCR takes only several hours.
A relatively new tool is adding to the confidence of local health officers that they are capturing in a timely way indicators of water quality problems at public beaches.
“It’s frustrating to use the culture-based method and come back the next day and say you shouldn’t have been swimming at this beach yesterday,” Briggs says. “We’re pleased how well the QPCR method is working for Michigan beaches.”
EGLE received approximately $280,000 in federal funds for monitoring of Great Lakes beaches and will pass on these and another $200,000 in state funds for monitoring of inland beaches this year. The money goes to local health departments, which, under the Michigan health code, are the lead agencies in monitoring public beaches. EGLE assists and supports local health agencies.
Although there is no state mandate that local health departments monitor beaches, if they do so, they are required to submit the resulting data for use in EGLE’s Beach Guard system. The searchable database allows users to seek historical and current data at particular beaches.
The latest State of the Great Lakes report issued by the United States and Canada characterized the conditions at beaches basin-wide as “good and unchanging.” This 2019 report noted approximately 1,000 beaches along the Great Lakes shoreline are monitored for E. coli each year.
“It’s frustrating to use the culture-based method and come back the next day and say you shouldn’t have been swimming at this beach yesterday. We’re pleased how well the QPCR method is working for Michigan beaches.”
Sources of pollution for the Great Lakes can include overflow from wastewater treatment plants, runoff from the land after a heavy rainfall, improperly working septic systems, and even large flocks of water birds. An advantage of the QPCR method is that it can show markers of specific pollution sources, enabling health and environmental agencies to address those sources.
