The lake that kept Portage residents out is safe again

*Kalamazoo County Health & Community Services lifted a public health advisory for Austin Lake* in Portage after recent water samples tested negative for microcystin toxins. The advisory had been in place for about two weeks, keeping swimmers, boaters, and pet owners on edge during the height of summer.

The lake sits just east of downtown Portage and is a popular spot for fishing, kayaking, and casual swimming. When the advisory went up in late May, residents who rely on the lake for recreation had to weigh the risks of getting in the water.

What triggered the advisory

On Wednesday, May 27, 2026, Kalamazoo County health officials sampled Austin Lake and found the water tested positive for microcystin. That is a type of cyanobacteria that produces toxins dangerous to both people and pets.

"These toxins can be harmful to humans and pets if they are exposed to the contaminated water, causing a range of potential health problems including skin irritation, gastrointestinal issues, and respiratory symptoms." — Kalamazoo County Health & Community Services Department, public health advisory issued May 27

The county warned that in severe cases, the toxins can cause neurological symptoms or organ damage in people. For pets, the risks are even more immediate. Symptoms in animals can appear within minutes to a few hours and can include vomiting, diarrhea, staggered walking, excessive drooling, and convulsions. Deaths can occur.

When the all-clear came

Samples collected on Monday, June 8, 2026 tested negative for microcystin. The health department announced the advisory was lifted the following day.

"The Kalamazoo County Health & Community Services Department has lifted the public health advisory for the suspected harmful algal bloom on Austin Lake after recent water samples tested negative for microcystin toxins." — City of Portage, June 8

What officials still advise

Even with the advisory lifted, health officials say harmful algal blooms can occur throughout the summer and fall. Residents and visitors are encouraged to keep monitoring lake conditions.

Officials recommend the following precautions:

  • Avoid water that appears blue-green or has a paint-like sheen on the surface
  • Rinse off people and pets with fresh water after any lake contact
  • Look for clear water and clean shores before entering
  • Contact a veterinarian immediately if a pet shows signs of illness after lake exposure

For additional information, the Kalamazoo County Health & Community Services Environmental Health Division can be reached at 269-373-5210.

The bigger picture

Harmful algal blooms are becoming more common across Michigan lakes as warmer water temperatures and nutrient runoff create ideal conditions for cyanobacteria growth. The State of Michigan has published a picture guide to help residents identify harmful algae and distinguish it from harmless lake conditions.

Austin Lake is not the only body of water in the region affected by algal blooms this season. Health officials across West Michigan have issued similar advisories for lakes in neighboring counties, underscoring the widespread nature of the issue.

For Portage residents who were told to stay out of the water for nearly two weeks, the negative test results are a welcome sign that summer on Austin Lake can resume normally.

Sources: