Keywords: Nonpoint Source Pollution, Storm water, Storm Drain, Stream Quality; Grades: 4-5; Lesson/activity Time: Three 45 – 60 minute classes


  • Describe what storm water is and explain the purpose of a storm drain
  • Define the term "nonpoint source pollution" and identify examples of it;
  • Suggest reasons why people create or contribute to nonpoint source pollution; and select strategies for reducing or preventing some forms of nonpoint source pollution.
  • Design an effective public service announcement to show how to reduce nonpoint source pollution
  • Work cooperatively to design a system to remove the simulated "nonpoint source pollution" from the simulated river


  • Analyze real-life situations to determine concerns, problems and potential solutions
  • Participate in group discussion and work together to problem solve.
  • Write an effective announcement to draw attention to nonpoint source pollution and how it can be reduced

Materials Needed

Set Up:
* An aquarium (non-leaking) with clear glass sides
* Water - should fill aquarium up halfway
* Cardboard box or box top - big enough to fit over top of aquarium
* Green and brown food coloring
* Two small bottles, cups or baby food jars each filled halfway with water
* Three brown, dry twigs, each 2 - 3" in length--Playdoh is an option for this as well
* A mix of soil, sand, leaves and pebbles - about 1 cup
* Vegetable oil - about ¼-cup
* Food scraps and food wrappers (about 1 cup)
* Yard waste - grass clippings, leaves, nuts and small sticks (about 1 cup)
* Paper waste - shredded newspaper, cardboard, tissues and paper (about 1 cup)
* One copy of list of seven scenarios (see below) - these should be cut up into seven slips of paper (laminate for longer life)
* A long stick or yard stick for stirring the watery mix
* Materials to create Public Service Announcements and Awareness posters
* Materials brought from students' homes to clean up the water

WARM UP: This lesson should be completed after students understand the concept of a watershed.

The purpose of the warm up is to elicit existing knowledge regarding the purpose of a storm drain, where it drains, and how it might impact the watershed. The following can be used to accomplish this:

  • Draw or show a picture of a storm drain to the class and ask the following questions:
  • "What is this called?" (Sewer or storm drain).
  • "Where are these typically found?"(Alongside curbs or embedded in pavement, parking lots, bridges, etc.)
  • Encourage stories regarding balls, toys or other items that have been accidentally dropped into storm drains or sewers by the students, their friends or family members. "Were you able to obtain these items? If not, where do you think the items went?"
  • "What is the purpose of a storm drain and how does it relate to a storm?" (Flood control measure).
  • "Where does water from snow or rain go after it enters a stormdrain?" (In most cases water is carried by a pipe into a nearby waterway). Introduce the term "stormwater" to the group.
  • "What other materials can enter storm drains with stormwater?" List suggestions on the board. Examples include litter, fertilizer, road salt, oil, sand, soil, leaves, twigs, animal waste and hazardous waste that have been dumped into drains or soil, etc.)
  • Explain that the group will make a storm drain in the classroom in order to learn more about its purpose and the types of materials that can fall into it.

Session 1: 45 - 60 minutes
1. Prior to the lesson: Place the aquarium in an area where it is easy to view by all of the students. Fill the aquarium halfway with water. This water represents the river that the storm water drains into after it has rained and the storm water that has traveled from a street through a storm drain and into the river.

2. Prior to the lesson: Cut a rectangular hole in the center of the box or box top that is large enough for someone's hand to fit through. Place the box or box top over the top opening of the aquarium - this cover represents the storm drain opening. Leave the aquarium's sides uncovered so students can view its contents.

3. The eight scenarios on the separate worksheets provide realistic examples of the types of water pollution that enter storm drains in neighborhoods and communities. These sheets should be cut up into eight slips of paper and each slip should be randomly handed out to groups of students. The simulated materials should be placed on a table and numbered appropriately for the scenarios.

4. Invite two student volunteers from each group to introduce each scenario - one student should read it to the class and the other student should find the corresponding material on the table and drop the "simulated pollution" into the storm drain (box opening on top of aquarium) when the reader is finished. After each scenario ask the class to draw conclusions regarding the concerns or problems that the scenario presents and ask them to take notes on these conclusions (as the information may be useful to them later.) It is also beneficial to ask if they meant to do each scenario and how many of them know someone who also does this.---The students will be very excited, so perhaps a recorder on the board would be better than on individual paper.

5. Use the yardstick or stick to stir the contents of the aquarium when the scenarios have all been completed, or as each is completed. This usually gets quite a reaction from the students. Collect the scenario cards for later use.

6. Ask students to examine the contents of the aquarium and describe how the quality of the water it contained changed during the activity. In a real-world setting, what do they think happens to these forms of water pollution? Review with them basic information about the water cycle, water movement, and watershed.

7. Discuss the definition of "nonpoint source pollution" and explain that the forms of pollution mentioned in the scenarios are all forms of nonpoint source pollution. Explain that nonpoint source pollution originates from the individual actions of residents and can occur anywhere (we cannot point to the offender) - in small communities and neighborhoods as well as in cities and suburbs.

8. Ask students: "Does this type of pollution harm the environment? If so, how?" Explain that the water quality of almost all of Pennsylvania's streams, rivers and lakes are effected in some way by nonpoint source pollution and it does factor into whether people can drink the water, swim in it or fish from it. It can also be harmful to the animals and plants that live in or near water. It is helpful to make a list on the board of ideas.

9. Ask students: "Do you think people in the scenarios wanted to damage the environment? Do you think they planned to pollute the water near them?" If so, have them explain why people might want to do these things. If not, have them guess why these people did what they did regarding their individual actions.

Session 2: 45- 60 minutes
1. Divide the class into small groups of 3 - 4 students and give each group one scenario (one slip of paper), a pencil and a piece of blank paper. Give them 5 - 10 minutes to address the problem in the scenario by answering the following questions:
- What is the concern in this scenario?- Can the activity being conducted by people be reduced or prevented from happening? If so, how? OR- Can this form of nonpoint source pollution be reduced by amount or prevented from entering the water cycle? If so, how?

2. Have each group design a public service poster and awareness announcement to limit the specific nonpoint source pollution evaluated. Each group should describe their poster and announcement and find a place to hang it in the school, or copy and send home to parents, post on websites, etc.


* Participation in group activity and discussion,
* Responses to questions from the teacher.
* Public service announcement


* Have students "invent" a method or mechanism that would remove unwanted chemicals, solid materials and/or floating objects from stormwater. Students should bring materials to class the next period. Give students a sample of the water and give them time to test their methods.
* Pour the final product into clear jars and compare the groups
* Award a "best method" certificate for cleaning up the water
* Be sure to reiterate that the goal is not to clean up what we have messed up, but to prevent it at the source!


  • Environmental Protection Agency,
  • Beneath the Shell…A Teacher's Guide to Nonpoint Source Pollution and Its Potential Impact on New Jersey Shellfish. New Jersey Department of Environmental Protection. First Printing 1991; Revised 1993; Reprinted annually from 1997 - 2002 and 2004; adapted from "Storm Drain Watch"(pgs. 46 - 48).
  • Storm Drain Watch Worksheet: Eight Scenarios (below)

Scenario #1: Mrs. Howard has two small trees next to the house porch. The trees attract wasps, mosquitoes and caterpillars. She sprayed the trees with a chemical to kill or drive away the insects. A storm occurs soon after she sprayed and most of the chemical is washed off the leaves and onto the sidewalk and driveway. From there it is washed with rainwater into the storm drain along the curb.

Simulated Pollution: Mix 2-3 drops of green food coloring with the water in one of the bottles. Empty this green water into the opening on top of the aquarium
Scenario #2: A small stream winds through a popular golf course. During a heavy rain the stream is filled with fast flowing water. In certain places the sides of the stream are wearing away and tree roots are showing. During and after each rain soil, sand, leaves, pebbles and other natural debris are swept away with the heavy flow of water as the shores of the stream slowly collapse. This material is eventually carried by the stream into the river that it empties into.

Simulated Pollution: Add the mix of soil, sand, leaves and pebbles into the opening on top of the aquarium.
Scenario #3: Susan enjoys helping her father change the motor oil in the family automobile. She clumsily carries the huge pan of black, thick used motor oil to the storm drain in front of their apartment building, where she dumps it. It's gone! Eventually the oil will mix with the water of a nearby stream or river; and any motor oil that she spilled onto the ground will go into the soil and mix with water that is underground.

Simulated Pollution: Empty the vegetable oil into the opening on top of the aquarium.
Scenario #4: One snowy winter evening the Palmer family heard raccoons outside opening and turning over their garbage cans left out by the curb, but it was too dark and cold to go outside and chase them away. The next morning no one in the family had time to clean up the litter that was strewn all over the street. When the snow melted most of the trash floated with the water into the storm drain.

Simulated Pollution: Add the paper waste through the opening on top of the aquarium.
Scenario #5: One of Matthew's jobs at home is to cut the lawn each week after school. When the grass catcher is full he dumps the grass clippings into the nearby ditch or sewer, whichever one happens to be closer to the lawnmower at the time. While in the ditch or drain the clippings turn yellow and begin to rot and smell until water from the next rainstorm carries the clippings away.

Simulated Pollution: Add grass clippings through the opening on top of the aquarium.
Scenario #6: Theresa enjoys walking the family dog, Patches. When Patches needs to go to the bathroom she is careful to make Patches go on the paved road along the curb so that Patches doesn't create a mess on the neighbors' lawn. She doesn't worry about picking up the mess because she knows that eventually the dog's waste will be washed with the rain into the nearby storm drain.

Simulated Pollution: Put the three twigs, or playdoh logs through the opening on top of the aquarium.
Scenario #7: The Smith family enjoys stopping at a fast-food restaurant for dinner while on their way to the beach for the weekend. To save time, the family eats inside their mini-van that is parked in the restaurant parking lot. In order to keep the car clean, they leave their bags of food trash on the pavement in the parking lot for the workers to pick up, since there are no trashcans in the parking lot. This family may not realize that animals and wind will eventually open up the bags and spread this trash around. If it isn't picked up it can be carried by rainwater during the next storm into a nearby storm drain.

Simulated Pollution: Add food scraps and food wrappers through the opening on top of the aquarium.
Scenario #8: A maintenance worker employed by a resident's association for some townhouses must take on new summer duties for the landscaper while he is out sick. These duties include lawn care for each of the residences. The procedure of spreading weed killer takes about three days to complete and two days after he began an all-day rainstorm kept him indoors. The maintenance worker failed to realize that the downpour would wash away most of the weed killer that was already applied on the lawns. In fact, the chemicals would most likely be washed
from plants and pavement into the nearby storm drains.

Simulated Pollution: Mix 2-3 drops of brown food coloring with the water in one of the small bottles.. Empty this brown water into the opening on top of the aquarium.


Susan Howard, Avon Grove Charter School, West Grove, PA