MACKINAC COUNTY, Mich. (WJMN) – The LMAS District Health Department announced Thursday that suspected harmful algal blooms (HABs) were detected in multiple locations on South Manistique Lake.

The department says it was notified by the Michigan Department of Health and Human Services (MDHHS) that algal blooms suspected to be blue-green algae, also known as also known as cyanobacteria or HABs were found near the lake’s north shore, south shore, and Shoepac Bay on the lake’s west shore.

LMAS recommends visitors to the lake avoid activities in the water and keep pets from going in or consuming lake water where bloom is visible until testing on the water is done or the bloom breaks up.

Samples of the bloom are being sent to the MDHHS for testing. Advisory signs regarding the bloom have been posted around the lake.

LMAS says it is not possible to tell whether algal blooms contain harmful toxins by looking at them, so it is recommended to avoid contact with any body of water that is covered with algal scums, mats or significant rafts of algae on the surface. You can search online at for verified reports of harmful algal blooms in Michigan or contact EGLE at 800-662-9278 for more information about HABs and the environment.

LMAS included the following recommendations regarding the HABs in a release:

Below are some steps to take when near waterways:

  • Avoid direct contact with waterways that appear to be scummy or have a green shade to them. This includes swimming, boating, tubing, skiing, playing in or allowing pets in the water in active bloom areas.
  • Do not drink untreated surface water
  • Obey posted signage for public health advisories and/or beach closings
  • Limit or avoid eating fish from algal bloom impacted areas

Contact with algae blooms can cause minor illness in humans but can be fatal to pets. Therefore, it is also
recommended that people keep their pets out of the water that shows any signs of algae blooms.

People and pets can experience the following symptoms after exposure to algae blooms:

  • Rash, hives, or skin blisters at skin contact site
  • Runny eyes and/or nose, sore throat, asthma-like symptoms, or allergic reactions
  • Diarrhea, vomiting, abdominal pain, weakness, tingly fingers, numbness,
  • Dizziness, difficulty breathing, or even death resulting from ingesting contaminated water

If you think you have been exposed to algae blooms, take the following precautions:

  • Immediately remove yourself and/or your pet from the area
  • Take a shower and thoroughly rinse off pets with clean, fresh water if they swam in an area with algae blooms to avoid potential toxic ingestion from licking their fur

If you think you or your pet may have been exposed to or ingested algal toxins, seek medical treatment for yourself and/or veterinary treatment for your pet as soon as possible.

Algal blooms are a normal part of lake and pond cycle. Harmful algal blooms need sunlight, slow-moving water, and nutrients, like nitrogen and phosphorus. Nutrient pollution from human activities makes the problem worse, leading to more severe and more frequent blooms. You can help reduce nutrient pollution by:

  • Choosing phosphate-free detergents, soaps, and household cleansers
  • When walking your pet, pick up after them and keep their waste away from waterways and waterbodies
  • Inspect your septic system annually to ensure proper function
  • When washing vehicles and watercraft, use nontoxic, phosphate free soaps and wash them on grass of gravel to filter the runoff before it enters the lake or stream