Name: _____________________
Watershed Simulation Lab
Class Period: ________
What is a Watershed?
A watershed is an area of land from which rainwater and snowmelt drain into a particular
body of water. Watersheds may be small areas of land that drain water into streams or
rivers or huge areas of land that drain into larger rivers, estuaries or deltas. A watershed is
usually named after the stream or river it drains into. By defining the boundary of a
watershed, people can determine what type of pollution affects a body of water and the
source of the pollution.
Map of the Chesapeake Bay Watershed
Map Reading Check Point: Label Elmira, NY and Binghamton, NY on the map above
Wacky Watershed
Objective:
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Students will become familiar with the terms, runoff, watershed, and land use.
Students will understand how runoff accumulates various materials (including
pollutants) and collects into a larger body of water.
Materials:
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Lid for a cardboard box
Newspaper, smaller boxes, cardboard (needed to contour the land)
Scissors
Washable markers
Small white trash bag
Medium binder clips
Spray bottle filled with water
Tape or glue (optional)
Procedure:
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Students will work in small groups, preferably 2 to 3 students per group. Each
group will need the materials listed in order to build their watershed model.
The box will serve as the base of the watershed. As a group, students will decide
which materials they will use to shape the “land” inside their watershed. Students
should include both high and low points in their model.
Once the bottom layer of the model has been assembled, place the trash bag over
the model so that it covers the contours of the model’s landscape. Use the binder
clips to secure the edges of the bag to the box lid.
After the trash bag is secure, students will use the markers to color various areas
of the trash bag. The different colors will represent different types of land use in
their watershed. Blue: forested areas; Brown: farms/agriculture; Red: mined
areas; Black: residential areas; Green: wastewater treatment plant; Yellow:
industrial areas/factories; Purple: development/construction. Students may
choose as many land uses as they wish or the teacher may choose for the groups.
Once the colors have been applied to the trash bag, the teacher should check the
setup of the watershed. Teacher should add some clear water to a low area of the
watershed before students will apply the “rainstorm”.
Students will use the spray bottle to simulate rainfall across their watershed and
watch how the water flows.
Observations
(Record your observations on a separate sheet of paper)
1. What is the relationship between slope of the landscape and stream velocity?
2. Our model watershed was able to move clay, silt and small sand particles,
how fast was our water moving in order to move these sediments?
3. Where were sediments eroding in our model, where were sediments
depositing? Why did this take place at these locations?
4. What is the relationship between sediment size and permeability?
5. What impact did urban development have on the permeability of the ground?
Discussion Questions
Based on the given maps, which Ground Cover is most abundant in the
Chesapeake Bay Watershed?
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In your opinion which ground cover was most harmful to a watershed? Why?
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