Students learn that dams do not last forever. Similar to other human-made structures, such as roads and bridges, dams require regular maintenance and have a finite lifespan. Many dams built during the 1930-70s, an era of intensive dam construction, have an expected life of 50-100 years. Due to inadequate maintenance and/or for environmental reasons, some of these dams will fail or be removed in the next 50 years. The engineers with Splash Engineering have an ethical obligation to remind Thirsty County of the maintenance and lifespan concerns associated with its dam.

Hydropower generation is introduced to students as a common purpose and benefit of constructing dams. Through an introduction to kinetic and potential energy, students come to understand how a dam creates electricity. They also learn the difference between renewable and non-renewable energy.

Students learn how the force of water helps determine the size and shape of dams. They use clay to build models of four types of dams, and observe the force of the water against each type. They conclude by deciding which type of dam they, as Splash Engineering engineers, will design for Thirsty County.

While the creation of a dam provides many benefits, it can have negative impacts on local ecosystems. Students learn about the major environmental impacts of dams and the engineering solutions used to address them.

Students conduct Internet research to investigate the purpose and current functioning status of some of the largest dams throughout the world. They investigate the success or failure of eight dams and complete a worksheet. While researching the dams, they also gain an understanding of the scale of these structures by recording and comparing their reservoir capacities. Students come to understand that dams, like all engineered structures, have a finite lifespan and require ongoing maintenance and evaluation for their usefulness.

Students further their understanding of the salmon life cycle and the human structures and actions that aid in the migration of fish around hydroelectric dams by playing an animated PowerPoint game involving a fish that must climb a fish ladder to get over a dam. They first brainstorm their own ideas, and then learn about existing ways engineers have made dams "friendlier" to migrating fish, before being quizzed as part of the game.

Students keep track of their own water usage for one week, gaining an understanding of how much water is used for various everyday activities. They relate their own water usages to the average residents of imaginary Thirsty County, and calculate the necessary water capacity of a dam that would provide residential water to the community.

Students are introduced to the structure, function and purpose of locks and dams, which involves an introduction to Pascal's law, water pressure and gravity.

Students reinforce their understanding of rocks, the rock cycle, and geotechnical engineering by playing a trivia game. They work in groups to prepare Jeopardy-type trivia questions (answers) and compete against each other to demonstrate their knowledge of rocks and engineering.

Students are introduced to the basic biology behind Pacific salmon migration and the many engineered Columbia River dam structures that aid in their passage through the river's hydroelectric dams. Students apply what they learn about the salmon life cycle as they think of devices and modifications that might be implemented at dams to aid in the natural cycle of fish migration, and as they make (hypothetical) Splash Engineering presentations about their proposed fish mitigation solutions for Birdseye River's dam in Thirsty County.

Students learn about Pascal's law, an important concept behind the engineering of dam and lock systems, such as the one that Thirsty County wants Splash Engineering to design for the Birdseye River (an ongoing hypothetical engineering scenario). Students observe the behavior of water in plastic water bottles spilling through holes punctured at different heights, seeing the distance water spurts from the holes, learning how water at a given depth exerts equal pressure in all directions, and how water at increasing depths is under increasing pressure.

Students learn about the importance of dams by watching a video that presents historical and current information on dams, as well as descriptions of global water resources and the hydrologic cycle. Students also learn about different types of dams, all designed to resist the forces on dams. (If the free, 15-minute "Water and Dams in Today's World" video cannot be obtained in time, the lesson can still be taught. See the Additional Multimedia Support section for how to obtain the DVD or VHS videotape, or a PowerPoint presentation with similar content [also attached].)

Students discuss several human reproductive technologies available today pregnancy ultrasound, amniocentesis, in-vitro fertilization and labor anesthetics. They learn how each technology works, and that these are ways engineers have worked to improve the health of expecting mothers and babies.

Students learn about the Earth's water cycle, especially about evaporation. Once a dam is constructed, its reservoir becomes a part of the region's natural hydrologic cycle by receiving precipitation, storing runoff water and evaporating water. Although almost impossible to see, and not as familiar to most people as precipitation, evaporation plays a critical role in the hydrologic cycle, and is especially of interest to engineers designing new dams and reservoirs, such as those that Splash Engineering is designing for Thirsty County.

Students are introduced to the concept of a dam and its potential benefits, which include water supply, electricity generation, flood control, recreation and irrigation. This lesson begins an ongoing classroom scenario in which student engineering teams working for the Splash Engineering firm design dams for a fictitious client, Thirsty County.

The engineers at Splash Engineering (the students) have been commissioned by Thirsty County to conduct a study of evaporation and transpiration in their region. During one week, students observe and measure (by weight) the ongoing evaporation of water in pans set up with different variables, and then assess what factors may affect evaporation. Variables include adding to the water an amount of soil and an amount of soil with growing plants.

Students perform a macroinvertebrate survey to gauge the health of a local river. They collect water samples and count macroinvertebrates to learn how the health of a river's ecosystem can be determined by its river insect population.

Student teams learn about and devise technical presentations on four reproductive technology topics pregnancy ultrasound, amniocentesis, in-vitro fertilization or labor anesthetics. Each team acts as a panel of engineers asked to make a presentation to a group of students unfamiliar with the reproductive technology. Each group incorporates non-lecture elements into its presentation for greater effectiveness. As students learn about the technologies, by creating a presentation and listening to other groups' presentations, they also learn more about the valuable skill of technical communications.