Billion Oyster Project

Watersheds Part 2 - Paper Watersheds


New York’s Urban Ecosystem Lessons



Class Periods




Subject Areas


Students will make a two paper models of watersheds to highlight the way water flows through a watershed.


  • Identify and understand a ridge from a valley

  • Understand and explain how water flows through a watershed

  • Observe a topographic map

  • Determine where the water flows on a topographic map

Materials and Resources


  • Paper (photocopy paper works well)
  • Tape
  • Washable markers
  • Spray Bottles
  • Water
  • Eyedroppers

Before you get started

Tips for Teachers

You need to choose a topographic map for this lesson. Use the website ArcGIS USA Topo Maps. Ideally, choose the topographic map of you Oyster Restoration Station (ORS) site or the location you brought your class for the lessons “Watersheds Day 1 - How does water flow through the watershed?” Take the time to study your topographic map before you give it to your students!! Some parts of the topographic map are harder to read than others, depending on how clearly the contour lines stand out from the street map. You can make your own version by tracing the desired area onto a transparency. That can then be photocopied and/or laid over the ArcGIS map to make the contour lines stand out more clearly. If neither of the above locations have enough of slope to work well for the activity, consider using the topographic map of the Gowanus Canal, because it is an excellent example of a watershed within New York City.





Instruction Plan


  1. Review vocabulary

  2. Review student work from previous lesson, “Watersheds Day 1 - How does water flow through a watershed?”

  3. Review “Land Conditions” data collected during previous expeditions to your Oyster Restoration Station (ORS).


  1. In this activity, students make a simple watershed model out of paper and spray water on it.

  2. Students get into small groups.

  3. Each group gets a piece of paper, marker and tape.

  4. Each group crumples up the paper.

  5. Students open the paper on the desk so they have a hilly terrain (i.e. a watershed model).  

  6. Tape the edges of the paper to a solid surface, such a desk. The paper should be taped down so it is relatively flush to the surface.

  7. Now introduce the vocabulary, and ask your students to identify what they think are the ridges, valleys, and the largest single watershed on their paper model.

    • Draw the ridgelines (high points) on the model to mark the watershed boundary using washable marker.

    • Explore the different parts of the model (e.g. hills and valleys).

  8. Spray the models with water using the spray bottle.

  9. Use the following discussion questions throughout the activity or in a worksheet.

    • Describe what the watershed model looks like.  What features does it include?

    • What features are similar to something you know or have seen outdoors?

    • Sketch your watershed model.  Add to your sketch throughout the activity.

    • What do you predict will happen when you spray water on your watershed model?

    • What happened when you sprayed water on your watershed model? Record your observations in words and/or diagrams.

    • Which direction did the water flow?  Did it flow quickly, slowly, or some of each? What factors seem to influence the speed and direction of the water flow?

    • Where did the water collect?  Did it collect all in one place, or in multiple places? Explain why you think it collected where it did.


  1. In this activity, will learn/review the basics of a topographic map.

  2. Each student gets a topographic map.  (The example below is the Gowanus Canal)

Screen Shot 2016-09-13 at 12.04.55 AM.png

  1. Explain or review topographic maps, contours and elevations.

  2. Note: Consider showing an image like the one below to illustrate how a topographic map represents a 3-dimensional landscape.


    1. Note: Consider taking the time to supplement this activity with a lesson about constructing a 3D model of a topographic map.

    2. Draw the ridgeline on the topographic map. (Students may need more help with this step if the concept of topographic maps is new to them. Start by looking at the highest contour lines adjacent to the water body.)



  1. In this activity, students will turn their flat, topographic map into a 3D watershed.

  2. Carefully pinch and fold the map, so the ridgelines are the highest point and the Gowanus Canal and the Harbor are the lowest points.

  3. Tape the edges of the paper to a solid surface, such a desk. The paper should be taped down so it is relatively flush to the surface.