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Student Resource Pages - Nonpoint Source Pollution

Cover-Freddie the Fish

Some rainwater goes straight into our lakes, rivers, and streams, but a lot of it falls on roads and in yards first. We call that "runoff." Runoff brings icky stuff like oil from the streets and fertilizer from our yards with it when it flows into lakes, rivers, and streams. That’s "nonpoint source pollution."

This cool interactive storm water runoff animation helps you understand:

Examples of Nonpoint Source Pollution:

Dog Poop

Danger: The bacteria in dog poop can make fish sick when run-off carries it from the land into the water. Yucky!


Danger: Fertilizer helps our lawns and flowers grow better, but when run-off washes fertilizer into the water plants there grow too fast and use up the oxygen fish need for breathing.

Motor Oil

Motor Oil

Motor Oil

Danger: Motor oil in the water coats fish’s gills, causing them to suffocate since fish need their gills to breathe. Run-off carries motor oil from our streets and driveways into streams and rivers.


Danger: Chemicals used to kill insects are called "pesticides" and too



many pesticides in the water can kill other things besides bugs – like fish!


Scientists Seining Fish Samples

Scientists Seining for Fish Samples

Danger: We spray "herbicides", or weed killers, on plants when we don't want them to grow, but when run-off brings herbicides into the water it can kill the plants and animals that live there.


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