WATER USE AND CONSERVATION
Grade Level: 7-10, can be adapted for elementary grades by summarizing simple facts in the article and shortening the survey to 3 days.
Subject: Environmental Science
Time Allotment: three 45-minute class periods, one week for home observations
Students read the article entitled "Getting Up to Speed" on the water cycle and water conservation.
Review the content of the article.
Students define the key term in their science journals: Clean Water Act, conservation, evaporation, hydrologic cycle, and transportation.
LEARNING ACTIVITY 1
World of Water Demonstration
Before the demonstration the teacher explains to the class that the amounts of water are relative quantities and are not actually proportions or amounts.
Put 3 gallons of water in an aquarium. Explain that this water represents all the water on earth.
In their science journals, students complete a 3-minute quick-write estimating what percent of this water is:
- Ice caps/glaciers
- Freshwater lakes
- Inland seas/ salt lakes
Using a measuring cup, the teacher removes 20 ounces of water from the aquarium. Using food coloring, color the remaining water in the aquarium. The dyed water represents the world's oceans. The water in the measuring cup represents all the water in the world that is NOT ocean water.
Pour 15 ounces of water from the measuring cup into clear container. This water represents ice caps and glaciers. Because it is in the form of ice, it is not readily available for use so it has to be separated from the world's supply of fresh water.
The remaining 5 ounces of water in the measuring cup represent the world's available fresh water. Of this water, only a small percent of an ounce composes the world's freshwater lakes and rivers. Use an eyedropper to collect this water and place it into a student's hand.
The water remaining in the measuring cup, after removing ice caps and glacier
water and freshwater lakes and rivers (about 4.5 ounces), is groundwater. Pour this water into a cup of sand and explain that this water is what is referred to as groundwater and that it is held in pore spaces of soil and cracks in bedrock.
Students complete the World of Water activity worksheet.
The answers to the drinking water percentages are: 0.419% total and 2.799% grand total.
Students review their estimates from the beginning of class and discuss their reactions to learning that there is such a small percentage of fresh drinking water in the world.
Students respond to the following questions in the science journal:
LEARNING ACTIVITY 2
- Why isn't all fresh water usable? It's not often easy to get to; it can be frozen or trapped in the soil; it is too polluted for use
- Why do we need to take care of the surface and ground water? Water is important for humans, plants, and animals; the more we use and waste, the less water there is available to use.
Discuss responses as a class.
H2O Diary: How much water do you use?
Brainstorm in science journals using the guiding questions: What are some of the ways water is wasted at home? How much do you think is wasted every day?
Students share responses in small groups.
Student groups record a list of daily activities that require using water and guesstimate how many gallons of water are used for each activity.
Pass out H2O Diary
Explain that before they begin the survey, students must make a hypothesis as to how much water an average person uses a day. Students record their hypothesis in their science journals and on the H2O Diary.
Students complete survey at home for a full week. Make clear that students must make tally marks each time the activity takes place.
After students have completed the survey, have students discuss the results in small groups. Students record their responses in their science journals. Use the following suggested discussion questions:
Share group discussions with whole class.
- What activity happened most often?
- Which activity used the most water?
- How much water is wasted by leaving the water running while brushing your teeth instead of turning it off?
- Electricity is a major user of fresh water. Water is used to cool the machinery used to produce electricity. Reducing your usage of electricity saves on water usage. Can you think of other industries that might use a lot of water?
- Why might your answers differ from your classmates' answers?
- Based on you survey, what can you and your family do to reduce the amount of water you use every day?
- Estimate how much water you would conserve by reducing your water use.
- Per day
- Per week
- Per year
Review ways in which individuals and families can conserve water.