Billion Oyster Project

A New York City Water Cycle


Unit

Nitrogen Cycle Investigation

Grade

6-8th

Class Periods

2

Setting

Classroom

Subject Areas

Science


Summary

Students will go outdoors to observe and document the water cycle in motion where they live. Students will also discover how they and their community impact not only the movement of water through the cycle, but also the water quality.

Objectives

  • Describe the movement of water through the water cycle.
  • Understand that water changes states when it gains energy from the sun or loses energy to the environment.
  • Understand that gravity causes water to move downhill and to precipitate from the clouds.
  • Create a model of the water cycle using the original pictures of water in the act of precipitating, infiltrating, condensing, running off, evaporating and transpiring.  

Materials and Resources

Supplies

  • sticky notes (one pad per group)
  • colored markers
  • projector cameras
  • buckets of water (if weather is uncooperative)
  • water sprayers (if weather is uncooperative)
  • printed student photographs and poster board/paper OR presentation software (e.g. Prezi, PowerPoint)

Before you get started

Tips for Teachers

Students will take their own photographs and then construct a water cycle diagram. If you plan on printing out the pictures and having the students arrange them on posterboard, you could consider having groups of 4-5. If the students will be using digital photographs arranged on something like Powerpoint or Prezi you should consider having students work in pairs. Consider whether you want a standard water cycle diagram available for students to look at any point in this lesson.

Background

The water cycle has no starting point. But, we'll begin in the oceans, since that is where most of Earth's water exists. The sun, which drives the water cycle, heats water in the oceans. Some of it evaporates as vapor into the air. Ice and snow can sublimate directly into water vapor. Rising air currents take the vapor up into the atmosphere, along with water from evapotranspiration, which is water transpired from plants and evaporated from the soil. The vapor rises into the air where cooler temperatures cause it to condense into clouds.
 
Air currents move clouds around the globe, cloud particles collide, grow, and fall out of the sky as precipitation. Some precipitation falls as snow and can accumulate as ice caps and glaciers, which can store frozen water for thousands of years. Snowpacks in warmer climates often thaw and melt when spring arrives, and the melted water flows overland as snowmelt.
 
Most precipitation falls back into the oceans or onto land, where, due to gravity, the precipitation flows over the ground as surface runoff. A portion of runoff enters rivers in valleys in the landscape, with streamflow moving water towards the oceans. Runoff and groundwater seepage accumulate and are stored as freshwater in lakes. Not all runoff flows into rivers [and lakes], though. Much of it soaks into the ground as infiltration. Some water infiltrates deep into the ground and replenishes aquifers (saturated subsurface rock), which store huge amounts of freshwater for long periods of time.
 
Some infiltration stays close to the land surface and can seep back into surface-water bodies (and the ocean) as groundwater discharge, and some groundwater finds openings in the land surface and emerges as freshwater springs. Over time, though, all of this water keeps moving, some to re-enter the ocean, where the water cycle "ends" ... oops - where it "begins."
 

AUCKLAND CITY COUNCIL 2010 Water Cycles.jpg


Instruction Plan

Engage

  1. Ask students the following questions:
    • What is precipitation?
    • What types of precipitation are there? 
    • What types of precipitation do we experience living here in NYC?
    • Which state is water in for each type of precipitation you named?
  2. Divide students into small groups. Give each group a stack of sticky notes and colored markers (each group gets a different color to write with). 
  3. Groups brainstorm what happens to the precipitation that falls here. Where does the water go? How does it get there? 
  4. Students write each idea on a separate sticky note. 
  5. Bring the class back together.
  6. Project the below image (or a similar image that shows a NYC scene with road, water, buildings and park) in front of the class.
  7. Facilitate groups/students coming up to the image and posting their sticky note on the photo. (e.g. “rain” could go in the sky, “runoff” could go by the edge of the dock, “infiltration” could go by the trees, etc.)
  8. Recap the students’ ideas. For example, “Rain falls onto the grass in the parks and infiltrates the soil.  Rain falls onto the street and runsoff the edge of the dock into the harbor.” Help the students understand that their sticky notes are all part of the water cycle.
  9. Have a set of water cycle sticky notes pre-written before class.  Fill in any gaps that the students missed (e.g. transpiration) and explain where it fits into the water cycle. 

 NYCwater-1-4.jpg

Explore

  1. Students will go outdoors and become water cycle sleuths. Students use a camera to capture water moving through the water cycle. For example, they are to catch water in the act of precipitating, running downhill, infiltrating, etc.
  2. Students will also photograph any human impacts on the water cycle.  For example, students could photograph (or possibly stage) litter that could get caught up in runoff.
  3. Ideally, students will have the opportunity to work outside on a day when it is raining, has just rained, or when snow is melting. If the weather is uncooperative, students can bring out water sprayers and buckets of water to simulate rain falling over different surfaces.
  4. Divide students into small groups. Give each group a camera and a copy of Water Cycle Photographs
  5. Go outdoors! Define the students’ work area. 
  6. Students work as a team to get the pictures they need and they fill out Water Cycle Photographs as they take each photograph. See examples below. 
  7. Bring students back together. Ask the groups which part(s) of the water cycle they have been unable to photograph. 
  8. Brainstorm as a class how to obtain the images they need. For example, students may suggest drawing a picture or using photoshop to depict evaporation or transpiration. (See Teacher Resources for links to simple transpiration activities.)
storm-drains-Los-Angeles-plumbing.jpg
 images.jpeg

Explain

  1. This lesson is an opportunity to introduce or reinforce the concept of Combined Sewer Overflows (CSOs).
  2. Water that doesn’t evaporate or infiltrate becomes surface water runoff. Surface water may flow over the ground surface or enter storm drains.  Water captured by storm drains flows downhill through sewer pipes (downhill direction determined by the pipe orientation) into a wastewater treatment plant. Stormwater shares these pipes with raw sewage (also called the sanitary sewer). The stormwater is treated and then discharged into the nearest body of water. However, when the sewer system becomes overwhelmed with storm water, both the raw sewage and storm water flow directly into the nearest body of water through combined sewer overflow (CSO) outfalls.  This means that almost every time it rains we have raw sewage flowing into our harbor.

Elaborate

  1. Students can take additional photos or create additional drawings in order to fill any gaps in their water cycle.
  2. Discuss the following with the class:
    • Did we leave any parts of the water cycle out?
    • When water isn’t in the process of evaporating, condensing, etc., where is it?
    • Identify the places water “rests”/is stored (harbor, rivers, puddles, clouds, plants, etc.) within the cycle.
    • Where do freezing (snow/glaciers) and melting fit in the water cycle?
    • Where do dew and fog fit in the water cycle?
    • Where does the water that the plants transpire come from?
    • Should we include capillary action as a force in the water cycle?

Evaluate

  1. Students will create a New York City Water Cycle model utilizing their photographs. Students can use PowerPoint, Prezi, or printed photographs and poster board to create their models. Each group should have one complete set of photographs to work with.
  2. To begin, students label each photograph with the part of the water cycle (or human impact) it represents. This activity can serve as an evaluation of students’ comfort with water cycle vocabulary. 
  3. Ask students to think about what makes water move through the water cycle. Why doesn’t the water just stay in the same state and in the same place forever? Give groups time to discuss amongst themselves.
  4. If students have a difficult time figuring out gravity and sunlight are responsible for water’s movement, show them a standard water cycle diagram and have them to look for clues.
  5. Students’ water cycle models should include all parts of the water cycle (processes and “resting” places); show the multiple paths water takes through the water cycle in New York City; and convey the idea that gravity and energy from the sun drives water’s movement through the cycle.

Standards

CCLS - ELA Science & Technical Subjects

    • Follow precisely a multistep procedure when carrying out experiments, taking measurements, or performing technical tasks.
    • Determine the meaning of symbols, key terms, and other domain-specific words and phrases as they are used in a specific scientific or technical context relevant to grades 6-8 texts and topics.
    • Include multimedia components and visual displays in presentations to clarify claims and findings and emphasize salient points.
    • Integrate multimedia and visual displays into presentations to clarify information, strengthen claims and evidence, and add interest.
    • Include multimedia components (e.g., graphics, images, music, sound) and visual displays in presentations to clarify information.

NYC Science Scope & Sequence - Units

  • Grade 6, Unit 2

    • Weather and Atmosphere

NYS Science Standards - Major Understandings

    • During a phase change, heat energy is absorbed or released. Energy is absorbed when a solid changes to a liquid and when a liquid changes to a gas. Energy is released when a gas changes to a liquid and when a liquid changes to a solid.