Billion Oyster Project

Watersheds Part 1 - Where Does the Rain Go?


New York’s Urban Ecosystem Lessons



Class Periods




Subject Areas



This lesson takes place in the field - ideally at your Oyster Restoration Station (ORS) site. This lesson would work well after you have completed the monitoring of your ORS. This lesson could also be done at any convenient location outside your classroom. Students will explore the area and make predictions about what happens to the water when it rains. Students will test their predictions with the actual pouring of water.


  • Observe carefully the slope and features of the surface of the ground

  • Predict where water will flow along the surface of the ground

  • Understand that slope and gravity affect water flow over the surface of the ground

  • Design a way to reduce runoff at the site.

Materials and Resources


  • Clipboard for each student
  • Water bottle full of water for each student
  • Extra water

Before you get started

Tips for Teachers

Visit your field location before bringing your students, so you have an idea of what’s there! Think about which features of the ground surface will be obvious to the students and which might be trickier for them to notice. Working outdoors or in the field goes more smoothly if every student has a clipboard! Trying to use folders, notebooks, or the backs of friends adds unnecessary distractions to an already distracting outdoor environment. You will need to bring extra water with you in the field, for use during the activity. It doesn’t have to be potable water. Consider using buckets with line to get water from nearby waterbody, carrying a gallon jug of water, or buying a portable water sprayer ($15-$150 from Home Depot). Consider a visit to the Queens Museum! They have a specific NYC water supply watershed exhibit (a lovely scale model), which also has life-size photos of water tunnels, as well as the better-known NYC scale model.


A watershed describes an area of land and how water flows in that area.  A watershed is a basin-shaped area of land defined by high points (ridges) and low points (the receiving water-body).  Imagine an umbrella turned upside down in the rain and how water would flow and collect in the center: the umbrella’s inner surface is acting as the watershed for the little pond that is forming inside it.  Since rain falls everywhere, all land is part of a watershed for some receiving body of water.  Water “sheds” or flows off the ridges, down the slope and into the lowest lying body of water, which may be a lake, reservoir or river.  As water flows downhill, it is also absorbed into the ground, lessening the amount that ends up directly running into the waterbody.

Instruction Plan


  1. In this activity, students observe the surface of the ground and predict where water will flow, where it will speed up and slow down, and what kinds of litter or pollutants they think it will pick up and/or drop in different places.

  2. In the classroom, make sure each student has a clipboard and give each student a copy of the Where does the rain go? Worksheet.

  3. Give the students a couple of minutes to look over the worksheet.

  4. Take the class outside.

  5. Ask: What happens to the rain that falls on this area?  

    • Examples: Slopes, hills, drains, grates, holes, cracks, curbs, roofs, downspouts, gardens, tree beds, waterbodies,

  6. Follow-up with probing questions, so students don't stop at their first thought.

    • Does that explain what happens to *all* of the rainwater?  

    • How much of the rainwater would you guess goes to this place vs. that place?  

    • What if it rains faster or slower?  Thundershower vs. drizzle?

    • What if it rains every day or just once a month?  

  7. Ask: are there pollutants and litter in this area?  

    • Where do you think flowing rainwater would pick up different pollutants and litter?  

    • Where do you think flowing rainwater would drop different pollutants and litter?

  8. Take note of information, misconceptions, questions, and dialogue among students.  

  9. Student complete questions #1 & 2 on their worksheet.


  1. In this activity, students will think about how to change the direction of the water flow.

  2. Engineering Challenge:  What would we have to do in order to make rainwater flow a different way, right here on the ground in front of us? 

  3. Note: We are not yet concerned about how to decrease runoff, (although take note if students are thinking along those lines as this issue will be raised later in the lesson).  In this activity we are trying to drive home the point about how slope and gravity affect water flow.

  4. Students complete question #3 on their worksheet.


  1. In this activity, students will think about how to change the direction of the water flow.

  2. Engineering Challenge:  What would we have to do in order to make rainwater flow a different way, right here on the ground in front of us? 

  3. Note: We are not yet concerned about how to decrease runoff, (although take note if students are thinking along those lines as this issue will be raised later in the lesson).  In this activity we are trying to drive home the point about how slope and gravity affect water flow.

  4. Students complete question #3 on their worksheet.


  1. In this activity, students will be testing their predictions of where water will flow.

  2. Explain: Now the students will be testing their predictions (inferences) of:

    1. where the water will flow

    2. Where the water will flow fastest and most slowly

    3. Where the water will pick up and drop different pollutants and litter
      Make sure students have made predictions before the water is poured.

  3. Students get into small groups.

  4. Students use their water bottles to pour water on the ground creating some flow.  Students should test several locations to test their predictions from earlier.

  5. Gather students back together.

  6. Explain: if students have monitored their Oyster Restoration Station (ORS) you might want to ask them to think back to the Land Conditions data they collected for Protocol 1 - Site Conditions.  See excerpt of data sheet below:

Land Conditions  (Take a photograph of the water with your camera)

Shoreline type:

Bulkhead/wall  |  Fixed Pier  |  Floating Dock  |  Riprap/Rocky Shoreline  |  Dirt or Sand |  Other

Estimate percent surface cover for the adjacent shoreline (about 100 x 100 feet)

_______% Impervious Surface (concrete/asphalt paths, roads, buildings etc.)

_______% Pervious Surface (dirt, gravel etc.)

_______% Vegetated surface (grass, shrubs, trees)

=______% Sum should equal 100%.

Garbage on the adjacent shoreline? Y / N


Hard Plastic

Soft Plastic










  1. Explain: Students might want to look for places to pour the water that highlight the following features:

    • Sediment that will flow along with the water

    • Litter or oil  that will flow along with the water

    • Permeable or impermeable surfaces

  1. Students complete question #4 on their worksheet and compare their results to their predictions.


  1. In this activity, students will think about how and why they could change runoff patterns in this area.
  2. Design Challenge:  What could we change or build on the surrounding buildings or ground surface that would either:
    • Decrease the amount of runoff that ended up in the nearby water-body or storm sewers -- in which case, where does the rainwater end up, and why is that better than runoff?
    • increase and direct runoff through a particular route -- in which case, what route do you choose, and why?
    • Choose one of these goals, and design for that goal.
  3. Encourage students to look back through their worksheets and to conduct some more water pouring experiments for design ideas.
  4. Then discuss: which goal is most appropriate for this location? Why? Multiple right answers are possible!


CCLS - ELA Science & Technical Subjects

    • Conduct short research projects to answer a question (including a self-generated question), drawing on several sources and generating additional related, focused questions that allow for multiple avenues of exploration.

NGSS - Cross-Cutting Concepts

  • Cause and Effect

    • Cause and effect relationships may be used to predict phenomena in natural systems.
  • Energy and Matter

    • Within a natural system, the transfer of energy drives the motion and/or cycling of matter.
  • Scientific Knowledge Assumes an Order and Consistency in Natural Systems

    • Science assumes that objects and events in natural systems occur in consistent patterns that are understandable through measurement and observation.

NGSS - Disciplinary Core Ideas

  • ESS2.A: Earth’s Materials and Systems

    • All Earth processes are the result of energy flowing and matter cycling within and among the planet’s systems. This energy is derived from the sun and Earth’s hot interior. The energy that flows and matter that cycles produce chemical and physical changes in Earth’s materials and living organisms.
  • ESS2.C: The Roles of Water in Earth's Surface Processes

    • The complex patterns of the changes and the movement of water in the atmosphere, determined by winds, landforms, and ocean temperatures and currents, are major determinants of local weather patterns.
    • Water continually cycles among land, ocean, and atmosphere via transpiration, evaporation, condensation and crystallization, and precipitation, as well as downhill flows on land.
    • Water’s movements—both on the land and underground—cause weathering and erosion, which change the land’s surface features and create underground formations.
  • ESS3.C: Human Impacts on Earth Systems

    • Human activities have significantly altered the biosphere, sometimes damaging or destroying natural habitats and causing the extinction of other species. But changes to Earth’s environments can have different impacts (negative and positive) for different living things.
  • ETS1.B: Developing Possible Solutions

    • Models of all kinds are important for testing solutions.

NGSS - Science and Engineering Practices

  • Asking Questions and Defining Problems

    • Ask questions that can be investigated within the scope of the classroom, outdoor environment, and museums and other public facilities with available resources and, when appropriate, frame a hypothesis based on observations and scientific principles.
  • Constructing Explanations and Designing Solutions

    • Apply scientific ideas to construct an explanation for real-world phenomena, examples, or events.
    • Apply scientific ideas or principles to design, construct, and test a design of an object, tool, process or system.

NYC Science Scope & Sequence - Units

  • Grade 6, Unit 2

    • Weather and Atmosphere

NYS Science Standards - Key Ideas

  • LE Key Idea 7

    • Human decisions and activities have had a profound impact on the physical and living environment
  • PS Key Idea 2

    • Many of the phenomena that we observe on Earth involve interactions among components of air, water, and land.
  • PS Key Idea 3

    • Matter is made up of particles whose properties determine the observable characteristics of matter and its reactivity

NYS Science Standards - Major Understandings

    • The environment may contain dangerous levels of substances (pollutants) that are harmful to organisms. Therefore, the good health of environments and individuals requires the monitoring of soil, air, and water, and taking steps to keep them safe.
    • During a physical change a substance keeps its chemical composition and proper- ties. Examples of physical changes include freezing, melting, condensation, boiling, evaporation, tearing, and crushing.
    • The rock at Earth’s surface forms a nearly continuous shell around Earth called the lithosphere.
    • The dynamic processes that wear away Earth’s surface include weathering and erosion.
    • Water circulates through the atmosphere, lithosphere, and hydrosphere in what is known as the water cycle.

NYS Science Standards - MST

    • Students will use mathematical analysis, scientific inquiry, and engineering design, as appropriate, to pose questions, seek answers, and develop solutions.
    • Students will apply the knowledge and thinking skills of mathematics, science, and technology to address real-life problems and make informed decisions.