Excessive Bacteria and Toxins at Spirit Lake Beach


Via Flickr

Josie Taylor | August 23, 2022

The water at a Spirit Lake beach recently had the highest concentrations of bacteria detected so far this year at any state beach in Iowa, along with an unhealthy amount of blue-green algae toxins, according to the Iowa Department of Natural Resources.

That means the DNR’s weekly test revealed more than 24,000 viable bacteria in less than a half cup of the lake water. The tests are unable to quantify the number of bacteria above that level.

In Iowa lakes that are prone to unhealthy concentrations of bacteria, a single test that detects 235 viable bacteria can prompt the DNR’s “swimming not recommended” warning. 

Bacteria concentrations in Iowa’s lakes can shift dramatically over the course of days, which is why the DNR samples state beaches once each week during warmer months when people are most likely to come in contact with the water. 

Spirit Lake has a fairly significant blue-green algae bloom right now near the beach that stretches into the lake for perhaps 50 yards. That’s the source of the toxin warning at the beach.