Nutrients are good, right? Not always. Too much of a good thing can be very, very bad for people, fish, and clean water.

The Problem: Nutrient Pollution & Toxic Algae Blooms

Too much phosphorus and nitrogen in water can be very harmful to aquatic life and to people. Phosphorus and nitrogen pollutants fuel the growth of algae, which at excessive levels leaves us with the green gunk-infested waters we’re all too familiar with in Illinois. These waters are nasty, and they stink. No one wants to swim in them, and when the algae decomposes, it robs the water of oxygen, making life difficult for fish and other aquatic creatures that depend on that oxygen. Nitrogen and phosphorus pollution from Illinois (and other states in the Mississippi River basin) has helped create a dead zone as large as the states of Connecticut and Rhode Island combined in the Gulf of Mexico where the oxygen is so depleted by decomposing algae that fish and other aquatic life can no longer live.

Certain forms of algae can also be toxic, as we saw in Toledo when algal toxins shut down that city’s drinking water supply in the summer of 2014. Many of Illinois’ rivers, lakes and streams are polluted by phosphorus and algae. For example, in 2014 at least 57% of Illinois lakes were suffering pollution problems due to phosphorus and/or algae.

Where does all this nitrogen and phosphorus pollution come from? In Illinois, the sources are almost equally split between sewage treatment plants and corn and soybean farms.

The Solution: Reducing Nutrient Pollution

At Prairie Rivers Network we are working with multiple partners to achieve, over the long term, reductions in nitrogen and phosphorus pollution through enhanced sewage treatment (like this agreement with the City of Joliet) and improved farming practices. Enhanced sewage treatment technologies, reduced fertilizer use and better farming practices can go a long way to significantly reducing these harmful pollutants and clean up the algae both at home and in downstream waters.

Clean Water Priorities


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