ST. JOSEPH — Berrien County and Michigan environmental officials are testing a potential algae bloom on Lake Michigan, about a mile offshore of St. Joseph, to determine if it is an organism that could be harmful to people.
Gillian Conrad, communications director of the Berrien County Health Department, confirmed that they were made aware of a visible blue-green patch on the lake’s surface late Monday by a resident who saw it near Lookout Park on Lakeshore Avenue.
The Michigan Department of the Environment, Great Lakes and Energy (formerly the Department of Environmental Quality) was alerted and samples of the surface water were taken Tuesday. In addition, the water treatment plants in St. Joseph and Benton Harbor sent their raw and treated water to a state lab to find if it contained any toxins related to the possible algae.
No results had been received by Wednesday afternoon, Conrad said. At this point there were no major health concerns, and the beaches remained open, she said. With the source of concern a mile from the shore, it is unlikely that swimmers could come in contact with it, she added.
Conrad heard from one of the environmental officials that the growth looked like duckweed, a small free-floating plant that looks like algae.
Whatever it turns out to be, winds from the east are likely to push the growth farther offshore, Conrad said.
Algae typically grows in warmer water and when there is chemical run-off. The most prominent algae bloom on the Great Lakes is the cyanobacterial bloom on Lake Erie, that continues to grow and now covers 620 square miles, taking up about 6 percent of the entire lake.
Hugh McDiarmid, with the Michigan Department of Environment, Great Lakes, and Energy, told Michigan Public Radio last week that cyanobacterial blooms have the potential to release toxins that cause harm to humans and animals.
“The symptoms of contact with toxic algae are rashes, hives, asthma-like symptoms,” McDiarmid told the radio station. “If you swallow toxins, you can develop flu-like symptoms, have abdominal pain. In great quantities it could conceivably harm your kidneys and liver.”
He said the toxins have also been known to harm dogs, who will go swimming and then often lick their fur. “It can happen pretty quick with the pets, where you see vomiting, fatigue, staggering, convulsions, and in rare instances it has actually killed dogs.”
Algae blooms can grow on inland lakes, and residents are advised to avoid contact with water with a green growth on its surface.
Conditions allowing for an algae bloom are different on Lake Michigan than on Lake Erie, which is the shallowest of the Great Lakes and has the smallest water volume, Conrad said.
Coincidental to the appearance of the suspected algae is a chemical spill last week into a tributary of Lake Michigan near Portage, Ind. The spill came from a steel plant, and shut down parts of the Indiana Dunes National Park and killed hundreds of fish.
“It’s important to note that we do not believe that there is any connection between the presence of algae in St. Joseph and the ammonia/cyanide spill in Portage, Indiana,” Conrad said. “In fact, the chemicals that were spilled would kill algae, rather than promote its growth. The samples gathered last week in New Buffalo showed non-detects for those chemicals, so we don’t have any further concerns with that situation.”
Contact: jmatuszak@TheHP.com, 932-0360, Twitter: @HPMatuszak