Module 5: Dam It All
- weigh the advantages and drawbacks of large dams, including economic, environmental, and cultural impacts;
- explain the reasons why dams are built, and the rationale for removing them;
- assess whether government agencies should be responsible for regulating new dam construction;
- debate whether a dam is the most appropriate solution to water needs and flood control in a particular location.
Context for Use
Description and Teaching Materials
In this module, students will:
- interact with online teaching materials pertaining to dams;
- read and respond to an article from Science Magazine on the effects of the Aswan Dam on the Nile River Delta;
- assess the costs and benefits (economic, environmental, and cultural) of the Three Gorges Dam;
- interact with a dam removal project database available online from American Rivers;
- adopt and defend a position on government regulation of dam building in developing nations.
All materials for students are available online using the Student Materials link below. These can be implemented entirely in the context of distance learning, with students completing any discussion questions in the form of a blog or discussion group. In a traditional or blended classroom setting, students can complete the online unit as homework, using class time for the Summative Assessment (Dam Debate).
Teaching Notes and Tips
This module somewhat stands alone, although it recognizes the need to alleviate potential problems associated with floods and drought covered in Module 4. Dams have been a major method of providing flood control, power, and a hedge against drought, but are now rather controversial because of their negative environmental impacts, among other problems. Dam building has diminished greatly in the United States but continues in much of the rest of the world, including China, Brazil, and Ethiopia. Through case studies in Module 5, students are provided with a general overview of the benefits and issues associated with dams, particularly through the details of Aswan Dam and the Nile River and the Three Gorges Dam on the Yangtze River. The Formative Assessments are straightforward and generally ask students to summarize what they have read in the module, particularly for Formative Assessments 1 and 2. Formative Assessment 3 asks the student to select a dam in the United States that is targeted for destruction or has been destroyed and to provide the reasons for bringing down that and other dams in general. Formative Assessment 4 requires students to provide more of an informed opinion regarding the future regulation of dam building internationally and to apply a fairness doctrine to such overarching controls. Most students responded thoughtfully to this assessment.
Students thoroughly enjoyed the dam debate. For larger classes instructors might consider expanding the list of dams, including Klamath Dam Complex in California, Grand Coulee Dam in Washington, Cochiti Dam in New Mexico, or local dams in your area of interest. For the in-class debate, instructors should be sure to (a) remind students to prepare for the Summative Assessment in advance of class, drafting a list of discussion points (or pros and cons); and (b) allocate ~20 minutes at the start of the class period for groups to organize materials and prepare their arguments.
What students found difficult
This material was generally accessible and non-quantitative, and no students appeared to struggle with the assessments. Perhaps the most difficulty was experienced during the Summative Assessment when the students were all required to contribute to a debate on the "pros and cons" of dams. Students were challenged by sometimes having to make arguments for a side with which they disagreed. The instructor might emphasize that this is an important skill to develop to become more effective in debates. In addition, we required each student to summarize one or more points for their debate team (generally four students to a team), and not all students were capable of framing cohesive thoughts or informative sentences.
Module 5 is nicely situated between two more challenging, quantitatively-oriented modules and allows students to take a bit of a breath. In general, the debates went very well and most students rose to the occasion, even when disagreeing with their side of the debate (assigned by instructor). Following the debate, we asked the students to reflect on how their opinions had changed, if at all, after studying Module 5 material and participating in the debate, which is a useful exercise in metacognition. A number of them had changed their stance from pro-dam to con. It is important to also emphasize that not all dams are particularly detrimental and that some contribute much to society. The future strategy for dam management in the United States (and eventually the world) is to identify those dams that provide the lowest benefit/cost ratio and prioritize those for removal. Some useful and engaging supplementary information is available in the documentary DamNation. As an alternative in-class discussion/activity, students could debate the pros and cons of damming Yosemite Valley, using the Hetch Hetchy reservoir as an example.
- Formative Assessment 1: The Nile's Sinking Future
- Formative Assessment 2: Three Gorges Dam
- Formative Assessment 3: Dam Removal
- Formative Assessment 4: Regulating Construction
- The Summative assessment for this module is Dam Debate.
References and Resources
- Readings from Student Materials — Module 5: Dam it all
- The Big Thirst: The Secret Life and Turbulent Future of Water by Charles Fishman: Chapter 7
- China's Great Dam Boom: A Major Assault on Its Rivers by Charlton Lewis, published at Yale Environment 360.