Fertilizer runoff endangers waterways

I am writing to bring attention to a serious issue that faces Lake County. For the past decade, there have been occasions in which local water quality has been compromised.

These include the 2021 closure of Diamond Lake in Mundelein, the Bangs Lake algae bloom in Wauconda in 2024 and the massive fish die-off in Valley Lake in Grayslake last year, just to name a few.

These events were all, in some way or another, a result of algae blooms. The events in Mundelein and Wauconda were the direct result of cyanobacteria. These microorganisms are dangerous for humans, with symptoms including skin and stomach problems. This is to say nothing of the threat these blooms pose to local wildlife.

Meanwhile, fish die-offs occur when the level of dissolved oxygen is too low in a body of water. Oxygen, in turn, decreases when there is a large amount of dead organic material in a body of water, which happens during algae blooms. Algae blooms are a direct result of an overabundance of nutrients in the water supply, which is typically a result of fertilizer runoff.

While some Lake County municipalities have voted to limit phosphorus-based fertilizers, not all have. Furthermore, the county government has done virtually nothing to address this issue.

I call on the county government, municipal governments and individuals to work together to restrict fertilizer runoff to solve this issue, namely by enacting broader, stricter fertilizer restrictions than those already in place.

Algae blooms hurt the local economy, the local environment and can even hurt people. More effort should be put into preventing this grave threat.

Isaiah Gauwitz

Grayslake