Hands-on Activity: Dam Pass or Fail
Educational Standards :
Pre-Req Knowledge (Return to Contents)
Basic Internet navigational skills. Familiarity with the four basic types of dams (embankment, arch, gravity, buttress) as described in lesson 2, Water and Dams in Today's World of the Dams unit, is helpful.
Learning Objectives (Return to Contents)
After this activity, students should be able to:
Materials List (Return to Contents)
Each student needs:
Introduction/Motivation (Return to Contents)
In today's world, dam failure or removal is a real possibility. Dams that were built 50 to 100 years ago are aging and failure can happen for any number of reasons. Let's brainstorm: For what reasons might a dam fail? (Take suggestions from students.) A dam could fail for all sorts of reasons, including inadequate inspection, faulty design, earthquakes, or lack of maintenance.
In recent years, more and more dams have been removed on purpose. For what reason would a dam be removed? Well, sometimes a dam is in such bad condition that it cannot be repaired and is unsafe, so it is removed to keep it from being a hazard. But more often, dams are removed for environmental reasons or because they no longer serve a useful (needed) purpose. Who can tell me what environmental reasons might cause people to want to remove a dam? (Possible answers: To improve river habitat, restore fish migration routes.) The Sierra Club is concerned about Splash Engineering's designing the two dams for Thirsty County because of environmental reasons. Who can guess what these reasons might be? (Take suggestions from students.) Some dams, such as the Edwards Dam in Maine, were removed because they caused more environmental harm than societal good. Communities must continually weigh the advantages and disadvantages of having dams on their local rivers. If a community concludes that the disadvantages outweigh the advantages, they might remove the dam. In fact, nearly 800 dams have been removed in the last 100 years (of the ~80,000 dams in the US).
How do we know the condition of our dams? Who is responsible for their inspection? Their maintenance? Their removal? Inspecting, and overseeing maintenance and the careful process of removal of dams are all responsibilities of engineers.
In this activity, you, the engineers of Splash Engineering, are going to use the Internet to research some existing dams so that we can learn about what works and what does not. You want your designs for Thirsty County to succeed. You want your designs to not fail in the same ways that previous dams around the world have failed. Learning about failed dams helps engineers avoid making similar design mistakes for new dams. Successful engineers study past designs to learn from them.
Raise your hand if you have ever done research on the Internet before. If you have not done much research on the Internet, you can think of the Internet like a big library that is easy to use because you don't have to lift heavy books off the shelf! Let's get started.
Vocabulary/Definitions (Return to Contents)
Procedure (Return to Contents)
Before the Activity
With the Students
Attachments (Return to Contents)
Troubleshooting Tips (Return to Contents)
Some students may not be familiar with Internet research, Internet browser applications or even computers. As necessary, provide appropriate tutorials in a prior class to prepare students for this activity.
Assessment (Return to Contents)
Review on the Board: Review the four types of dams by drawing them on the board (see Lesson 2). Ask students to name the four different dam types (embankment, arch, gravity, buttress) and what they are made of (embankment dams are made from earth and rock; the rest are made of concrete.)
Activity Embedded Assessment
Activity Worksheet: Have students individually complete the Does the Dam Pass or Fail? Worksheet while completing their Internet research Review their answers to gauge their mastery of the subject.
Class Discussion: As a class, discuss the worksheet results. Ask the students:
Activity Extensions (Return to Contents)
Ask students to make a bar graph detailing the purposes of the eight researched dams. The graph should show how many dams are used for hydropower, flood control, irrigation, navigation, and recreation (and any other purposes discovered through the research).
Assign further research into dams being removed for environmental reasons. In Oregon, dam removal has been completed or proposed in order to restore salmon passage to natural conditions. How did the river adjust to the resulting sediment left by the removed dam? Assign students to research the pro and con arguments of actual cases, such as the Marmot Dam on the Sandy River, the Savage Rapids Dam on the Rogue River, and four dams on the Klamath River. Example resources: http://or.water.usgs.gov , http://www.usbr.gov , http://seattletimes.nwsource.com.
Assign another direction for research: Some people characterize dams as "19th century solutions to 21st century problems." So, what is the future of dams? Are dams needed anymore? What are alternatives to dams? Why might dams not work for the 21st century? See the California's Statewide River Conservation Organization's Friends of the River website at http://www.friendsoftheriver.org – Why Dams Don't Work" and http://www.friendsoftheriver.org - Alternatives to Dams.
Activity Scaling (Return to Contents)
Additional Multimedia Support (Return to Contents)
What happens when a dam collapses? Can engineers model the collapsing of a dam? What is the link between predicting earthquakes and crumpling a piece of paper? See the many resources available at Cracking Dams, a SimScience website that provides lesson plans, teacher guides, case studies, computer simulations, movies, scenarios, quizzes and glossaries at http://simscience.org/cracks/.
Resources to investigate dam failures:
Resources to investigate dam removals:
References (Return to Contents)
Building Big: All About Dams. Public Broadcasting System Online. 2000-01. WGBH Educational Foundation. Accessed October 14, 2009. http://www.pbs.org/wgbh/buildingbig/dam/index.html
Dams and Dam Removal. 2001-07. Department of Natural Resources, Michigan. Accessed October 14, 2009. http://www.michigan.gov/dnr/0,1607,7-153-10364_27415---,00.html
Ladd, Chris. Published July 23, 2009. Dam It All. Good.Is Magazine. Accessed October 14, 2009. (Good recap article on the state of dams, present and future, in the US, including failures, removals and river recovery.) http://www.good.is/post/dam-it-all/
Nearly 800 Dams Already Removed across US. Posted November 26, 2008. The Society of Environmental Journalists, Jenkintown, PA. Accessed October 14, 2009. http://www.sej.org/publications/tipsheet/nearly-800-dams-already-removed-across-us
ContributorsJeff Lyng, Kristin Field, Denali Lander, Megan Podlogar, Denise W. Carlson
Copyright© 2008 by Regents of the University of Colorado.
Supporting Program (Return to Contents)Integrated Teaching and Learning Program, College of Engineering, University of Colorado Boulder
Acknowledgements (Return to Contents)
The contents of this digital library curriculum were developed under a grant from the Fund for the Improvement of Postsecondary Education (FIPSE), U.S. Department of Education and National Science Foundation GK-12 grant no. 0338326. However, these contents do not necessarily represent the policies of the Department of Education or National Science Foundation, and you should not assume endorsement by the federal government.