Water Pollution: Where Does it Come From?
Context: Almost 20% of the world’s fresh water is found in the Great Lakes, providing Michigan with access to a massive supply of water. We rely on this freshwater source for drinking water, cleaning, growing food, and transporting goods. Unfortunately, humans are also responsible for significant amounts of water pollution, from a variety of sources, which impacts the quality of the freshwater in the Great Lakes. This activity provides more information on the importance of our Great Lakes, the threats facing them, and how to identify the point and nonpoint sources of water pollution.
Goals: Age Group: 6th - 12th grade
Learn about different types of water pollution
Think critically about the ways humans impact our natural environment
Consider strategies to reduce water pollution
Supplies: Time: 30 minutes
(Optional) Paper and writing utensil to record your answers
First, watch this short video on the importance of our Great Lakes: https://www.youtube.com/watch?v=gBRcOLcEwF0
As mentioned in the video, different pollutants are threatening the quality of water in the Great Lakes. Pollutants are substances that are not typically found in nature, that humans release into the environment. Types of water pollutants can be broken down into two categories, point and nonpoint sources.
Point sources: Water pollution coming from a single place or source, for example, chemicals released from a factory.
Nonpoint sources: Smaller amounts of water pollution that come from many places over a given area, and combine to equal a large amount of pollution. During rain events, nonpoint sources of pollution can end up in water runoff, making their way to our water bodies. For example, think of individual people littering along a roadway, then a rain storm carries the collective litter to a nearby river.
Use these definitions to identify which of the following pictures of pollution are point sources or nonpoint sources. Afterwards, check your answers at the end of this page.
Lastly, take time to answer the following reflection questions.
Identify Point and Nonpoint Sources:
1. Description: Pesticides (chemicals to prevent insects) on someone’s lawn. Point or nonpoint source?
2. Description: Oil on a road from passing cars. Point or nonpoint source?
3. Description: An oil spill in the Gulf of Mexico (Deepwater Horizon spill). Point or nonpoint source?
4. Description: Plastic bags and garbage left on the sidewalk. Point or nonpoint source?
5. Description: Washing a car in a driveway, soapy water flows down into the street. Point or nonpoint source?
6. Description: A factory releases their pollution into the river. Point or nonpoint source?
7. Description: With heavy rainfall, a wastewater treatment facility (a place that ‘cleans’ our water after we’ve used it) is overwhelmed and untreated water is released into a river. Point or nonpoint source?
Did anything surprise you from the video? Did you learn anything new about the Great Lakes?
What benefits of the Great Lakes were mentioned in the video?
What are the negative effects of water pollution? Think of ways pollution impacts humans, plants, and animals.
Do you think point or nonpoint sources of water pollution are harder to stop? Why?
What are things that individuals can do to reduce water pollution? Think of different behaviors.
How can the government play a role in stopping water pollution? For point and nonpoint sources?
Answers for Identifying Photos: 1 - nonpoint, 2 - nonpoint, 3 - point, 4 - nonpoint, 5 - nonpoint, 6 - point, and 7 - point.