Water Tower Challenge

Build Materials (For each team)

Required Materials

• 50 Plastic/Paper Straws
• 50 Pipe Cleaners
• 25 Paperclips 

Testing Materials (per team)

• 1 Golf Ball or similar size/weight ball

Materials (per team)

• 1 Golf Ball or similar size/weight ball

Process

Test the strength of each structure by placing the ball on the tower at a point no more than 20% below the upper height of the tower.

Learn how a water tower works with the use of pressure. (Video 2:20) 

https://www.youtube.com/watch?v=ZI8WOzqHl7w

Source: City of Bloomington MN YouTube Channel

See a picture tour of the top 10 coolest water towers in the world. (Video 2:11)

https://www.youtube.com/watch?v=FYxkJnDgK9s

Source: all Top Ten YouTube Channel

You’re a team of engineers given the challenge of developing a water tower out of everyday materials that can “supply” and “shut off” water as needed. The water tower must be able to deliver water or a water substitute to a paper cup that is about 36 in/90 cm away in a controlled manner. 

Criteria 

• Must be able to deliver water or a water substitute to a paper cup that is about 36 in/90 cm away in a controlled manner. 
• Must be able to stop and start the flow of “water” to fill the cup half way up.

Constraints

• Can use only the materials provided.
• Unused building materials can be shared or traded with other teams.

1. Break class into teams of 2-4.
2. Hand out the Water Tower Challenge worksheet, as well as some sheets of paper for sketching designs. 
3. Discuss the topics in the Background Concepts Section.
4. Review the Engineering Design Process, Design Challenge, Criteria, Constraints and Materials. If time allows, review “Real World Applications” prior to conducting the design challenge. 
5. Before instructing students to start brainstorming and sketching their designs, ask them to consider the following:

• How your design will stop and start the flow of water
• The shape of your tower’s reservoir
• How a water tower works using hydrostatic pressure

6. Provide each team with their materials.
7. Explain that students must develop a water tower from everyday items. The water tower must be able to deliver water or a water substitute to a paper cup that is about 36 in/90 cm away in a controlled manner. You must be able to stop and start the flow of “water” to fill the cup half way up.
8. Announce the amount of time they have to design and build (1 hour recommended). 
9. Use a timer or an on-line stopwatch (count down feature) to ensure you keep on time. (www.online-stopwatch.com/full-screen-stopwatch). Give students regular “time checks” so they stay on task. If they are struggling, ask questions that will lead them to a solution quicker. 
10. Students meet and develop a plan for their water tower. They agree on materials they will need, write/draw their plan, and present their plan to the class. Teams may trade unlimited materials with other teams to develop their ideal parts list.
11. Teams build their designs. 
12. Test the water tower designs by demonstrating how their water tower delivers water or a water substitute to a paper cup within the defined criteria.
13. As a class, discuss the student reflection questions.
14. For more content on the topic, see the “Real World Applications” and “Digging Deeper” sections.

Variation

Have students test their designs to see if they are scalable by doubling and tripling the distance from the water source to the cup.

Student Reflection (engineering notebook)

1. How similar was your original design to the actual water tower your team built?
2. If you found you needed to make changes during the construction phase, describe why your team decided to make revisions.
3. Which water tower that another team made was the most interesting to you? Why?
4. Do you think that this activity was more rewarding to do as a team, or would you have preferred to work alone on it? Why?
5. If you could have used one additional material (tape, glue, wood sticks, foil — as examples) which would you choose and why?
6. Do you think your design is scalable? Would it work efficiently if the cup were 360 inches or 900 cm away from the water source? Why? Why not?

The lesson can be done in as little as 1 class period for older students. However, to help students from feeling rushed and to ensure student success (especially for younger students), split the lesson into two periods giving students more time to brainstorm, test ideas and finalize their design. Conduct the testing and debrief in the next class period.

What is a Water Tower? 

A water tower is a large elevated drinking water storage container that is engineered to safely hold a water supply at a height sufficient to pressurize a water distribution system. It needs to be big enough to supply residents of a community, or a building, with water, and also maintain the quality of the water that is stored and delivered. There are many designs for water towers all over the world.  

Some have become landmarks and are decorated whimsically. In certain areas, such as large cities, smaller water towers are constructed for individual buildings. Early water towers were often designed as part of a building.  What does the one in your town look like? 

What is Hydrostatic Pressure? 

Hydrostatic pressure is the pressure exerted by a fluid at equilibrium due to the force of  gravity. It is the pressure of the water that forces water to flow through pipes into  homes. If the pressure is not strong enough, water will not be delivered, or will be  delivered too weakly to suffice for some applications such as fire hoses or showers. The  higher the tank is and the larger the tank is, the more pressure and force that the water  will have. Sometimes pumps are also used to push water through the water delivery system, especially at peak usage times. When engineers design a water tower, they know that every vertical foot adds .43 pounds per square inch to the water pressure. (Note: 1 psi equals 6,894.76 Pascals.) Most towns regulate water pressure at between fifty and one-hundred pounds per square inch, so a simple equation tells them how high to build the tower.  

Building a Water Tower 

A wide range of materials are used to construct water towers — including steel and  reinforced concrete, with an interior coating to protect the water from any effects from  the building material. The reservoir in the tower may be in many shapes, and they usually  have a minimum height of approximately 6 metres (20 ft) and are a minimum of 4 m (13  ft) in diameter. Most water towers have a height of about 40 m (130 ft).The illustration to  the right shows: 1. A pumping station to push water up int o the water, 2. A reservoir to  hold the water, and 3. Examples of how the water might be used in a home, office, or  apartment building. 

Water Conservation

As you consider your town’s water system, think about the many ways homes and  businesses could conserve water and reduce the amount of water the town needs to provide. Here are several ideas: 

• Plumbing Modifications: install indoor plumbing fixtures that save water or replace existing  plumbing equipment with equipment that uses less water. A good example is a Low-Flush  Toilet that requires about a third of the water needed by conventional toilets. Another  example is a Low-Flow Showerheads. Showers account for about 20 percent of total  indoor water use and low flow heads use about half the water that conventional  showerheads do. Or, consider installing faucet aerators which break the flowing water  into fine droplets and mix air into the water while maintaining wetting effectiveness. 
• Lawn and landscape maintenance is an area where homes and businesses use large  amounts of water, particularly in areas with low rainfall. One method of water  conservation in landscaping is to select plants that need little water.  
• Changing Water Use Behaviors 
  • There are many ways to save water in homes and businesses…here are a few ideas: 
    • Run the dishwasher only when it is full. If dishes are washed by hand, water can be saved by filling the sink or a dishpan with water rather than running the water continuously.  
    • Turning off the faucet while brushing teeth or shaving.  
    • Take shorter showers.  
    • In the laundry room, adjust water levels in the washing machine to match the size of the load. Or, only run the machine when it is full. 
    • If you must water a lawn, do it early in the morning or late in the evening and on  cooler days, when possible, to reduce evaporation.

• Constraints: Limitations with material, time, size of team, etc.
• Criteria: Conditions that the design must satisfy like its overall size, etc.
• Engineers: Inventors and problem-solvers of the world. Twenty-five major specialties are recognized in engineering (see infographic).
• Engineering Design Process: Process engineers use to solve problems. 
• Engineering Habits of Mind (EHM): Six unique ways that engineers think.
• Hydrostatic Pressure: Pressure exerted by a fluid at equilibrium due to the force of gravity. It is the pressure of the water that forces water to flow through pipes into homes.
• Iteration: Test & redesign is one iteration. Repeat (multiple iterations).
• Potable Water: Fit or suitable for drinking.
• Pressurize: Exerting a steady force upon a surface.
• Prototype: A working model of the solution to be tested.
• Pumping Station: A house where pumps are installed and operated.
• Reservoir: A place where large amounts of water get stored.
• Scalable: Capable of being easily expanded or upgraded on demand. 
• Water Distribution System: Part of water supply network with components that carry potable water from a centralized treatment plant or wells to water consumers.
• Water Tower: A large elevated drinking water storage container that is engineered to safely hold a water supply at a height sufficient to pressurize a water distribution system.

Internet Connections

Water Towers

Recommended Reading

• Water Towers (ISBN: 978-0262022774)
• Design for Water: Rainwater Harvesting, Stormwater Catchment, and Alternate Water Reuse (ISBN: 978-0865715806)

Writing Activity 

Write an essay or a paragraph about environmental challenges to a water tower design. Consider how the weather, topography, the population of an area, or other factors might impact the design of a new water tower.

Alignment to Curriculum Frameworks

Note: Lesson plans in this series are aligned to one or more of the following sets of standards:  

• U.S. Science Education Standards (http://www.nap.edu/catalog.php?record_id=4962)
• U.S. Next Generation Science Standards (http://www.nextgenscience.org/) 
• International Technology Education Association’s Standards for Technological Literacy (http://www.iteea.org/TAA/PDFs/xstnd.pdf)
• U.S. National Council of Teachers of Mathematics’ Principles and Standards for School Mathematics (http://www.nctm.org/standards/content.aspx?id=16909)
• U.S. Common Core State Standards for Mathematics (http://www.corestandards.org/Math)
• Computer Science Teachers Association K-12 Computer Science Standards (http://csta.acm.org/Curriculum/sub/K12Standards.html)

National Science Education Standards Grades K-4 (ages 4-9)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry 
• Understanding about scientific inquiry 

CONTENT STANDARD B: Physical Science

As a result of the activities, all students should develop an understanding of

• Properties of objects and materials 
• Position and motion of objects 

CONTENT STANDARD E: Science and Technology 

As a result of activities, all students should develop

• Abilities of technological design 
• Understanding about science and technology 

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Types of resources 
• Science and technology in local challenges 

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor 

National Science Education Standards Grades 5-8 (ages 10-14)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry 

CONTENT STANDARD B: Physical Science

As a result of their activities, all students should develop an understanding of

• Motions and forces 

CONTENT STANDARD E: Science and Technology
As a result of activities in grades 5-8, all students should develop

• Abilities of technological design 

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Populations, resources, and environments 
• Science and technology in society 

National Science Education Standards Grades 5-8 (ages 10-14)

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor 
• History of science 

National Science Education Standards Grades 9-12 (ages 14-18)

CONTENT STANDARD A: Science as Inquiry

As a result of activities, all students should develop

• Abilities necessary to do scientific inquiry 

CONTENT STANDARD B: Physical Science 

As a result of their activities, all students should develop understanding of

• Motions and forces 
• Conservation of energy and increase in disorder 

CONTENT STANDARD E: Science and Technology

As a result of activities, all students should develop

• Abilities of technological design 
• Understandings about science and technology 

CONTENT STANDARD F: Science in Personal and Social Perspectives

As a result of activities, all students should develop understanding of

• Personal and community health 
• Natural resources 
• Science and technology in local, national, and global challenges 

CONTENT STANDARD G: History and Nature of Science

As a result of activities, all students should develop understanding of

• Science as a human endeavor 
• Historical perspectives 

Next Generation Science Standards Grades 2-5 (Ages 7-11)

Matter and its Interactions 

Students who demonstrate understanding can:

• 2-PS1-2.  Analyze data obtained from testing different materials to determine which materials have properties that are best suited for an intended purpose.

Motion and Stability: Forces and Interactions

Students who demonstrate understanding can:

• 3-PS2-1. Plan and conduct an investigation to provide evidence of the effects of balanced and unbalanced forces on the motion of an object.

Next Generation Science Standards Grades 2-5 (Ages 7-11)

Engineering Design 

Students who demonstrate understanding can:

• 3-5-ETS1-1.Define a simple design problem reflecting a need or a want that includes specified criteria for success and constraints on materials, time, or cost.
• 3-5-ETS1-2.Generate and compare multiple possible solutions to a problem based on how well each is likely to meet the criteria and constraints of the problem.

Next Generation Science Standards Grades 2-5 (Ages 7-11)

Engineering Design 

Students who demonstrate understanding can:

• 3-5-ETS1-3.Plan and carry out fair tests in which variables are controlled and failure points are considered to identify aspects of a model or prototype that can be improved.

Next Generation Science Standards Grades 6-8 (Ages 11-14)

Engineering Design 

Students who demonstrate understanding can:

• MS-ETS1-1.  Define the criteria and constraints of a design problem with sufficient precision to ensure a successful solution, taking into account relevant scientific principles and potential impacts on people and the natural environment that may limit possible solutions.
• MS-ETS1-2 Evaluate competing design solutions using a systematic process to determine how well they meet the criteria and constraints of the problem.

Standards for Technological Literacy – All Ages

The Nature of Technology

• Standard 1: Students will develop an understanding of the characteristics and scope of technology.
• Standard 3: Students will develop an understanding of the relationships among technologies and the connections between technology and other fields of study.

Technology and Society

• Standard 4: Students will develop an understanding of the cultural, social, economic, and political effects of technology.
• Standard 5: Students will develop an understanding of the effects of technology on the environment.
• Standard 6: Students will develop an understanding of the role of society in the development and use of technology.

Design

• Standard 8: Students will develop an understanding of the attributes of design.
• Standard 9: Students will develop an understanding of engineering design.
• Standard 10: Students will develop an understanding of the role of troubleshooting, research and development, invention and innovation, and experimentation in problem solving.

Abilities for a Technological World

• Standard 11: Students will develop abilities to apply the design process.
• Standard 13: Students will develop abilities to assess the impact of products and systems.

Engineering Teamwork and Planning

You are part of a team of engineers given the challenge of developing your own water tower than can deliver water to a paper cup that is about 36 inches or 90 cm away in a controlled manner.  This means you must be able to stop and start the flow and fill the cup up just half way.  You’ll be given a range of items to build with, but first with design your system on paper, then build it and test it.  You’ll reflect on the experience, and present your designs to your class.

Research Phase

Read the materials provided to you by your teacher. If you have access to the internet, explore your town’s water delivery system and see how engineers designed your local water tower.

Planning and Design Phase

Engineers have built many different designs for water towers, but they all achieve the same goal of delivering water in a controlled manner to homes and businesses.  Now it is your turn!  In the space below or on a separate piece of paper, draw a detailed diagram showing the plan for your water tower.

Presentation Phase
Present your plan and drawing to the class, and consider the plans of other teams.  You may wish to fine tune your own design.

Build it!  Test it!
Next build your tower and test it.  You may share unused building materials with other teams, and trade materials too.  Be sure to watch what other teams are doing and consider the aspects of different designs that might be an improvement on your team’s plan.

Reflection

Complete the reflection questions below:

1) How similar was your original design to the actual water tower your team built?

2) If you found you needed to make changes during the construction phase, describe why your team decided to make revisions.

3) Which water tower that another team made was the most interesting to you? Why?

4) Do you think that this activity was more rewarding to do as a team, or would you have preferred to work alone on it? Why?

5) If you could have used one additional material (tape, glue, wood sticks, foil — as examples) which would you choose and why?

6) Do you think your design is scalable? Would it work efficiently if the cup were 360 inches or 900 cm away from the water source? Why? Why not?

• Swahili