Too much of a good thing

Looking out from the forrest over the St. Croix river

All plants need phosphorus to grow. Phosphorus in fertilizers keeps grass green and helps farmers raise crops.

But phosphorus doesn't always stay where we put it. Some of it washes into rivers, where it makes algae grow. This can lead to serious problems.

Phosphorus levels in the St. Croix increased significantly after the 1940s. Though they have now leveled off, another rise in the future could can seriously damage this beautiful habitat.

A dock with boats along the St. Croix river
Every year, over one million people enjoy fishing, swimming, boating and other activity on the St. Croix River.
(Photo courtesy of 1000 Friends of Minnesota)

What good is a river?

Plenty! Minnesotans love the outdoors. Over one million people a year use the St. Croix River for recreation—fishing, swimming, canoeing, relaxing. This beautiful natural area also supports many jobs.

But phosphorus—from lawns, farms and sewage—pollutes the St. Croix. And as our population grows, the problem will only get worse. If we take action now, we can keep enjoying the river for many years to come.