Water Pressure
Description
Of all the water on earth, 97.5 percent is salt water. Of the remaining 2.5 percent fresh water, some 70 percent is frozen in the polar ice caps. The other 30 percent is mostly present as soil moisture or lies in underground aquifers. In the end, less than 1 percent of the world's fresh water (or only about 0.007 percent of all water on Earth) is readily accessible for direct human use.
As the human population grows, the pressure on available water intensifies. The purpose of this lesson is to look at water usage in the United States and Africa and to gain a clearer understanding of the problems facing both areas of the world as the population increases and as natural resources are stressed.
Time Frame
Six 50-minute class periods
Curricular Areas
Geography, language arts, math, world history
Grades
9–12
Essential Questions
Why is there a disparity of resource use between developing and industrialized nations?
Why do nations need to work together to solve resource problems?
Materials
Fact Sheet: Use of Water Worldwide (PDF or RTF)
Graph paper
Colored pencils
Art supplies, poster board
Internet access for students
Evaluation Rubric (PDF or RTF)
Standards
Geography Standard 1—Understands the characteristics and uses of maps, globes, and other geographic tools and technologies
Benchmark—Transforms primary data into maps, graphs, and charts
Geography Standard 16—Understands the changes that occur in the meaning, use, distribution, and importance of resources
Benchmark—Understands programs and positions related to the use of resources on a local to global scale
Geography Standard 17—Understands global development and environmental issues
Benchmark—Understands why policies should be designed to guide the use and management of Earth's resources to reflect multiple points of view
Language Arts Standard 4—Gathers and uses information for research purposes
Benchmark—Uses a variety of primary sources to gather information for research topics
Benchmark—Determines the validity and reliability of primary and secondary source information and uses information accordingly in reporting on a research topic
Benchmark—Synthesizes information from multiple research studies to draw conclusions that go beyond those found in any of the individual studies
Language Arts Standard 8—Demonstrates competence in speaking and listening as tools for learning
Benchmark—Makes formal presentations to the class
Benchmark—Responds to questions and feedback about own presentations
Math Standard 5—Understands and applies basic and advanced concepts of statistics and data analysis
Benchmark—Selects and uses the best method of representing and describing a set of data
World History Standard 44—Understands the search for community, stability, and peace in an interdependent world
Benchmark—Understands major reasons for the great disparities between industrialized and developing nations
National Science Education Standards
Content Standard F: Science in Personal and Social Perspectives
Objectives
Students will
- Participate in discussions about their own water resources, the resources of Namibia, and global water resources.
- Transform primary data on world water usage into a graphic representation of it (using either an electronic spreadsheet or pencil and paper.
- Gather information using a variety of primary sources, and synthesize them to form their own conclusions.
- Make a poster that illustrates their solution to a problem.
- Make a formal presentation to the class using their posters to illustrate their conclusions and solutions.
Procedure Day 1
1. Grab student attention by asking "Do you do anything during the day that takes you three hours?" Then begin by discussing the facts about water highlighted below. They are from WaterPartners International: (www.water.org).
Every day more than a billion people will make a three-hour journey on foot just to collect water.
How do you think your life would be different if you had to walk three hours every day just to get water? (Possible answers: less time for other things, might appreciate water more, would not bathe as often, would not drink as much.)
There is enough water on Earth to cover the United States with a blanket 93 miles thick.
If there is so much water on Earth, why is there a problem with water use and supply? Why do people have to walk so far to get some? (Possible answers: Not all water is potable; some is salty or polluted. Some water is not accessible, located in underground aquifers. Also, water is not evenly distributed. Deserts get less rainfall than do rain forests.)
A quarter of the world's population—1.5 billion people—lacks access to safe water supplies.
Imagine if every fourth person in the room didn't have clean, safe water. What would happen to the friendships in the room? (Possible answers: people might be resentful; maybe fights would break out; some people would try to share, others would hoard water.)
Average Hondurans spend 25 percent of their income on drinking water. The average American spends .5 percent of his or her income on drinking water.
What would change in your life if you had to spend a quarter of your income on drinking water?
More than 25,000 people die every day from water-related diseases. Worldwide, that is more than 80 million people in the last eight years.
What is a water-related disease? (Possible answers: diseases such as giardia and dysentery that come from drinking parasitically contaminated water. Other water-related diseases come from a lack of water (dehydration), from parasites that use water to breed (malaria), and conditions that thrive where refugees share too little water for hygiene (typhus, cholera). Do you know anyone who has had a water-related disease? Did you ever know anyone who died of a water-related disease?
In the last eight years, 130 people in the United States have died of water-related disease.
If so many people worldwide die every day from water-related diseases, why does it happen so relatively seldom in the United States? (Possible answers: clean water, easily accessible water.)
2. For homework, ask the students to write a reflection about what they learned about water supplies. Ask students to write about the question, "What are your feelings about the disparity of water resources that we learned about today?" The intent is to keep students thinking about water issues.
Day 2
1. Spend a few moments at the beginning of class to go over the homework assignment in small groups. Students should share their reflections in their small groups.
2. Pass out "Fact Sheet: Use of Water Worldwide" PDF or RTF).
3. Give the class an overview of the facts on the sheet. Point out the various countries on the map. Domestic water use consists of water for drinking, bathing, and such. Discuss the differences you see in the raw data.
4. Give each student two different colored pencils and graph paper. Instruct the students to make a bar graph of the information on the sheet, with gallons on one axis and countries on the other. Color the African countries in one color and the North America countries with the other. (See Follow-up Activities below for instruction to make this a computer-based activity using Excel.)
5. Discuss the differences you see on the chart. The more industrialized nations use a great deal more water than the others. Why is that? (Possible answers: cheap, easy access to water; greater natural supply of water; flush toilets versus squat toilets.)
6. At the end of class, have students add more thoughts to their reflection on what they have learned about water usage.
Day 3
1. Introduce the Water in Africa website to your students. Have students work in pairs reading the stories and looking at the pictures of Namibia. Students should direct their research to the essential questions," Why is there a disparity of resource use between developing and industrialized nations?" "Why do nations need to work together to solve resource problems?" Suggest that they read the sections Conservation, Daily Usage, and The Source of Our Water first, and then look at other stories and pictures. It works well if the students take turns reading the stories out loud to one another.
2. At the end of class, make a web on the board of the main ideas that the students came up with about water usage in Africa. Themes might include the following: Namibia is a desert country; people use much less water there than in North America; people and animals sometimes share water; water is recycled. Leave the work on the board, overhead, or paper chart to help students with their projects for the next two days.
Days 4 and 5 (Can take longer if you wish)
1. Divide the class into small groups. Tell the students that they are going to work together to create a plan for Namibia to access and share water with its neighbors. Remind the students of the essential questions, "Why is there a disparity of resource use between developing and industrialized nations?" "Why do nations need to work together to solve resource problems?"
2. Start by reading a case study about water availability in Namibia. Search the Web for the keywords "case study, namibia, water crisis" to find suitable content.
3. Discuss difficult vocabulary: desalinization, aquifers, delta, hydrologists. Summarize the problems in Namibia (i.e., rainwater evaporates quickly without replenishing aquifers, no rivers, population is changing from being nomadic to stationary, desalinization plants create excessive pollution, etc.) What is Namibia's solution? (Divert water that now flows to Botswana.) What is wrong with this solution? (Will hurt delicate ecosystem, takes water from people who live along the delta, will cause political problems with Botswana.)
4. Have students brainstorm in their groups to come up with what they would like to know more about. Remind them of what they learned on the Water in Africa site. For example, one group may want to focus on researching desalination plants to find out if there are less-polluting models. Another group might want to research the Okavango River area of Botswana to understand the issue of the delicate biome there. Another group might want to research rainwater collection systems. Let each group decide what area of the problem they want to focus on.
5. Instruct the groups that they have the next two days to research and come up with a solution to Namibia's problem. On the fifth day, students will present their solution to their classmates in the form of an oral presentation and poster illustrating their solution. Emphasize that this is a short time, so their presentations don't have to be perfect. (Nations spend years coming up with good solutions to problems.) All solutions should be based on research and students' impressions from the Water in Africa website.
6. Allow students the rest of the class period and the next day to work on researching their problems. Students may need help finding what they are looking for on the Internet. A list of helpful water websites is included. Provide the evaluation rubric (PDF or RTF) to students prior to assigning homework so that the requirements for the plan are clear as they are building it.
Assessment
The students present their plans to the class. At the end of the presentations, the class can vote on which plan is the most feasible, the most creative, etc. Final projects should be assessed using the evaluation rubric.
Follow-up Activities
Have students research water-use issues in the United States. For example, there is a great debate over the Colorado River and California's consumption of water. A good resource is PBS's miniseries "Cadillac Desert."
Bring in gallon jugs to represent the amount of water used in various countries to give students a visual representation of the amount of water used every day in countries around the world.
Investigate the biomes of the countries involved to see if the landscape of a country affects its water resources and usage.
Instead of a paper-and-pencil graph on Day 2, students can experiment with Microsoft Excel to make graphs on the computer.
Get more information about water systems, the comparative cost of water, and lots of good definitions about water usage in the Water Handbook at http://www.unicef.org/programme/wes/pubs/glines/water.htm
Additional Resources
Material World : A Global Family Portrait. Peter Menzel. Sierra Club Books. 1994. A great book of photographs of families all over the world surrounded by their belongings. Contains a page of pictures of toilets of the world.
Water Science for Schools http://ga.water.usgs.gov/edu
Water Partners International http://www.water.org
World Water Day www.worldwaterday.org
Water Aid Educational Activities www.wateraid.org.uk
Exploris www.exploris.org
World Health Organization at http://www.who.int/inf-fs/en/fact112.html
Issues about drinking water in the United States can be found at these websites:
The Environmental Protection Agency at www.epa.gov
The U.S. Geological Survey at http://water.usgs.gov/
The National Water Resources Association at http://www.nwra.org About the Author
Carly Sporer Garrett is a teacher at Palomar High, a continuation school in Chula Vista, California. She served in the Peace Corps in Mongolia in 1995–96. After she piloted this unit with her class, she reflected:
"I began the unit by talking about some water-related facts. The kids got into that discussion, and it was really fun. That night they reflected on what they learned. The next day we looked at water usage facts and made bar graphs to show the disparity in usage between Americans and those in other countries in the world. That was a nice way to integrate math, and it made them shocked even more. We are lucky to have so many students who were born in Mexico, so they had a greater understanding of water usage, telling stories from personal experience. (Hauling water, not bathing so much, getting sick, etc.) We posted the graphs and moved into the rest of the unit. The students ended up with a lot more knowledge of water usage, and the week has been pretty enjoyable for them. They are not the best Web-researchers around, so it is kind of frazzling for me to run back and forth helping everyone find appropriate materials. Hopefully this unit improved that skill a little, also."
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