FOCUS AREA | WATER QUALITY

Protecting and improving the water quality in Lake Poinsett is critical to our enjoyment of life on the lake. Lake Poinsett is one of the largest natural lakes located in eastern South Dakota. Past studies of the flows entering the lake have revealed high levels of bacteria, sediment, and algae nutrients (e.g. nitrogen and phosphorus). These contaminants can threaten the quality of the water in Lake Poinsett. 

Have you ever seen the lake turn green and slimy, almost like someone spilled paint on the water? This is caused by algae, and it thrives when nitrogen and phosphorus make their way into the lake. 

Algae are common plant life in a lake and are an important part of the ecosystem. Most of the time, algae are generally harmless. But sometimes, things get out of balance: with enough nutrients like nitrogen and phosphorus, algae can grow exceptionally fast, like weeds in a garden. Algae overgrowth can lead to a number of issues. 

The water can change color (usually green but sometimes blue or even red), and it can also start to smell like rotten eggs. The real problem, however, is that some of these algae can produce toxins. These toxins can hurt animals like fish, frogs, and even birds. People or pets can also get sick from these toxins if they swim in or drink contaminated water.

Harmful algae blooms aren't just unpleasant to look at—they can be genuinely dangerous for the environment and for us. 

With the Lake Poinsett Management Plan, we will explore ways to limit algae nutrients entering the lake and protect it for years to come.