Sustainable Water Solutions: Weighing the Pros and Cons

How do we assess the benefits and drawbacks of various solutions to a problem? To decide how one potential solution compares to another, we have to consider the pros and cons of each from many dimensions: environmental, social, cultural, and economic.

About This Lesson

In this activity, students will work together to map out the strengths and limitations of potential solutions to some important water use and conservation issues. This lesson is part of a larger unit whereby students practice different steps in design thinking within the context of issues surrounding our global water system. In this exercise, students will practice comparing potential solutions in order to prepare for the culminating activity of the unit: a design thinking challenge.

Essential Questions

What are the advantages and disadvantages of different solutions that have been proposed for global water issues we are facing in the world today?
How do we assess the environmental, social, cultural, and economic benefits and drawbacks of various solutions to a problem?
How do we ultimately decide what solution is the ‘best’?

Learning Objectives

Students will

Explore some of the solutions being proposed for global water issues like our growing need for freshwater, water waste, groundwater depletion, and agricultural water use.
Learn how to evaluate and compare various solutions to a problem by mapping out the multidimensional strengths and weaknesses of each.

Materials

Computer lab with one computer for every student (computers should have Internet access) and one computer that the instructor can project from
One pair of audio headphones for each student
Projector
Five Flipside Science videos in the Fresh Solutions unit
Student Worksheets (1 per student, also available in Spanish, Simplified Chinese, and Traditional Chinese)
Supplemental readings (optional)

Pre-activities

We recommend you progress through the Your Hidden Water Footprint, Exploring Our Growing Need for Water, and Rapid Brainstorming lessons before continuing with this one. You can also use this lesson independently.

Part I: Exploring global water issues (15 min.)

Teacher note: If you preceded this activity with the Exploring Our Growing Need for Water and/or Rapid Brainstorming: How Can We Conserve Our Water Resources? activity, you can skip to Part II.

1. Hand out to students or write on the board a list of questions for them to think about while they watch the How Do We Meet the Growing Need for Water? video (see below).

2. Show students the video.

3. Ask student to jot down some of their thoughts about the questions that they were asked to consider while watching the video. Give them 5-10 minutes to do this. You might want to play the video another time through for students. Discuss these questions as a class after students have had a chance to reflect individually.

What kinds of water issues were raised in the video?
Where can we find freshwater on the earth? What are some freshwater reservoirs, or places where it is stored?
Why is a growing population a concern for our water resources?
What is one impact of overpumping groundwater? What do we use groundwater for?
Who/what uses water? Who/what is the largest user of water?
In what ways is water wasted?

4. Ask students to choose one of the main water issues introduced in the video on which to focus (growing need for freshwater, water waste, aquifer over-pumping, and agricultural water use) and to find a partner who chose the same issue. Note: To expedite this process or if you would like to ensure that all water issues are represented, you can also have students pick water issues out of a hat and pair up that way too.

Part II: Comparing water conservation solutions (25 min.)

1. Hand out one Student Worksheet to each student. Explain to students that they will be watching videos that will introduce them to some possible solutions that people have thought of for the issue on which they are focusing.

2. With their partners, students will guide themselves through the activity as outlined on their Student Worksheets. During this time, students will be asked to watch the Flipside Science water solution video for the problem they chose and they will proceed through an exercise weighing the pros and cons of the solution(s) introduced in the videos. Remind students to wear headphones while watching the videos on their own computers. As they work, walk around the classroom and ask different groups to explain their thinking. Probe them to uncover environmental, social, cultural, or economic factors that relate to proposed solutions.

Teacher tip: The solutions introduced in the Flipside Science videos are not the only solutions, nor necessarily the best solutions for the water issues they address. To help you facilitate students’ evaluations of these different solutions, we’ve created a Supplementary Materials document for each solutions video. Each document contains more information about the solutions outlined in the videos, as well as the pros and cons of these solutions. It is recommended you familiarize yourself with these materials before this activity.

3. Remind students when they have 15 minutes and 5 minutes left in the activity.

Wrapping Up (20 min)

1. Come back together as a class, and ask students share out (in 1-2 minutes) the water issue they focused on and the pros and cons of the solutions they explored.

2. Ask students to reflect on their experience.

Do we have one perfect solution for each of these issues? Why or why not? Do you think one exists?
What steps can we take to try to develop the best solutions we can?
What does it mean to consider the different ‘dimensions’ of a problem or solution? (E.g., economic, environmental, social, cultural, etc.)
Why is it important for you (as young people) to think about these issues?

Additional Resources

KQED Science: Why Isn’t Desalination the Answer to All California’s Water Problems?
NPR KQED Public Radio: Why California Farmers are Conflicted About Using Less Water
San Francisco Public Utilities Commission: Recycled Water
San Francisco Public Utilities Commission: Groundwater
California Academy of Sciences Science News: Water Use: Drought and Beyond

Connections to the Next Generation Science Standards

NGSS Disciplinary Core Ideas (Grades 6-8)

MS-ESS3.C: Human Impacts on Earth System

Science and Engineering Practices (Grades 6-8)

Defining and Delimiting Engineering Problems

California's Environmental Principles and Concepts

Principle I: Concept c
Principle II: Concept a, b, c
Principle V: Concept a

Up Next: Design Thinking Challenge

Culminating Activity: Design a Solution
Challenge your students to apply their newly cultivated skills to design a solution to a water issue at home or school! Choose from a spectrum of challenges to find one that suits your available class time and resources.

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Fresh Solutions: About This Unit

Humans depend on water, and our need for this precious resource is growing alongside our population. How will we meet the needs of the future without harming the environment? In this unit, we'll explore environmental issues related to our water use, and learn how simple choices we make impact our planet.