What is runoff?

Runoff is any water that flows across the surface of the land.  The main source of runoff is precipitation.  However, anytime you wash your car or water your lawn you are creating runoff.

Runoff carries pollution including nutrients, chemicals and sediment into our waterways.  Think about all the things that are on our roads and yards.  Gas and oil from cars, fertilizers and pesticides from our yards, waste from our pets…runoff carries all of these things into our rivers and streams. 

Chemicals and pesticides can be harmful to aquatic plants and animals.  They can also be harmful to people that use the river for swimming or fishing.  Excess nutrients from fertilizers and pet waste can lead to algae blooms.  These blooms can cause the water to be cloudy, discolored or to have a bad odor.  When the algae bloom dies the dissolved oxygen levels in the water drop.  Low dissolved oxygen can often cause fish kills.