Earth Water Distribution and Water Consumption

Keywords: freshwater, saltwater, groundwater, glacier water consumption, direct water consumption; Lesson Plan Grade Level: seventh through twelfth grade; Total Time Required for Lesson: 40 minutes; Setting: classroom Laboratory

Goals for the Lesson

  • Students will gain a visual perspective on global water distribution and average U.S. water consumption.
  • Students will understand the limited supply of fresh water that exists on the earth.
  • Students will explore the need for not polluting and conserving our fresh water supply.

Materials Needed

  • two 1000-ml beakers per group
  • one 100-ml graduated cylinder
  • access to tap water
  • one quart of vegetable oil
  • one bottle of blue food coloring
  • one stirring rod per group

State Standards Addressed: E & E Standards: Watersheds and Wetlands (4.1.10E, 4.1.12E)

Teaching Model: Experiential Learning Model

Subjects Covered: biology, chemistry, ecology

Topics: global water distribution, VS water consumption goals

Preparation

  1. The students will read background material from text and handouts from USGS handouts from USGS Web site .
  2. The students will then complete the exercise and answer the questions on the question page in Appendix 1 based on the handouts and their exercise.

Doing the Activity

  1. Students should do this exercise in pairs, possibly in groups of three.
  2. Collect two 1000 mL beakers and label them beaker 1 and beaker 2.
  3. Beaker 1 will represent the world's water distribution in terms of fresh US salt water. First, measure out and pour into the beaker 970 ml of water. Add 2 drops of blue food coloring to the water and stir. This represents the ocean portion.
  4. Next, students will pour 30 ml of vegetable oil into the beaker. This portion will float representing the world's fresh water portion.
  5. Next, the student will get beaker 2 and add prospective portions of water to represent average US water use.
  6. Add water to beaker 2 according to the following format and notice how full the beaker becomes with each water use addition:
  • Water Additions
  • Use Ml of Water
  • Dishwasher 30 ml
  • Toilet Leaks 50 ml
  • Baths 90 ml
  • Faucets 120 ml
  • Showers 210 ml
  • Washing Machines 220 ml
  • Toilet Flush 280 ml
  1. Set the beakers aside and now answer the question in Appendix 1.
  2. Student must wash beakers and put away when finished.

Assessment

Students will do the exercise and complete questions to be turned in for a grade.

Conclusion

This exercise is fairly quick and easy but provides a good visual picture of how we use water and how much is actually available for use.

Reference

Drohan, Joy, William Sharpe, and Sanford Smith (2001). Water Conservation with the Water Lion. University Park, Pa.: Center for Watershed Stewardship, The Pennsylvania State University.

Dubay, D. (1999). Environmental Science. New York: Addison Wesley Longman Inc.

USGS Web site: Water Science Section

Author

Jere White, Liberty Junior/Senior High School