Nutrients, such as phosphorus and nitrogen, are the biggest problems for lakes.
Think of nitrogen and phosphorus as food for plants. They’re very important. But too many nutrients in water can cause certain annoying plants to grow wild in your lake or river. Also, you should not drink water that has too much nitrogen in it.
“Sediment,” or soil washing into lakes from nearby land, is a big problem too. Sediment washing into lakes can harm fish and other forms of life, burying eggs and making it hard for some fish to hunt food.
According to the U.S. Environmental Protection Agency, about 22 percent of the lake and pond acreage in the country is harmed by nutrients. About 9 percent of U.S. lake acres are harmed by eroding soil, or sediment.
Green plants grow wild on a lake. Many of these plants are a type of algae.
Photo: USDA NRCS