Experts warn about bacteria in Missouri waters

ST. JOSEPH, Mo. (News-Press NOW) -- Across Missouri, reports of waterborne bacteria and related illnesses have been on the rise.

One of the most recent and alarming cases involved an individual who contracted a brain-eating amoeba after swimming in the Lake of the Ozarks.

Areas that prohibit swimming are often not regularly tested, which means bacterial levels in those waters are largely unknown.

Waterborne bacteria thrive in warm temperatures, particularly in the late spring and early summer months when water temperatures range from the 70s to the low 80s.

However, once water temperatures reach the upper 80s and into the 90s, many harmful bacteria begin to die off, struggling to survive in such heat.

While the St. Joseph region doesn’t offer local freshwater beaches or designated swimming areas, there are still plenty of options for outdoor recreation, especially fishing.

Eric Dennis, a fisheries biologist with the Missouri Department of Conservation, provided insight into local water safety and bacterial concerns.

"Ninety-nine percent of the time, it’s going to be perfectly fine to eat fish caught from potentially contaminated waters — especially around here,” Dennis said. “We don’t have a lot of areas with high enough bacteria levels to cause harm."

When it comes to waterways getting tested for swimming safety, Dennis said the MDC only tests areas where recreational swimming is permitted.

Dennis added that cooking fish thoroughly will eliminate most harmful bacteria and parasites, making them safe to consume even if the water quality is questionable.

Though swimming might not be common in local waterways, Dennis noted that it’s typical for dog owners to let their pets swim or drink from natural bodies of water. He issued a warning about one particular threat: harmful algal blooms.

“Don’t let your dog go near any body of water that looks greenish, blue, olive green, or even red,” Dennis said. “That’s a sign of a blue-green algae bloom, which can be extremely harmful for dogs to ingest — or even breathe.”

As temperatures rise and outdoor activities increase, experts urge residents to stay informed and cautious about the hidden risks in Missouri’s waters.

Before deciding whether to enjoy one of Missouri's waterways, remember the Missouri Department of Natural Resources' helpful reminder: "When in doubt, stay out."

For more information on Missouri's waterways and bacteria, visit: https://dnr.mo.gov/water/hows-water/pollutants-sources/harmful-algal-blooms-habs