Dams

Overview of lesson/activity topics: Lesson 1, the varied reasons why people build dams; lesson 2, the four main types of dam construction; lesson 3, Pascal's law and water pressure, and lock systems for river navigation; lesson 4, hydropower generation, falling water and waterwheels, turbines and generators, non/renewable energy sources; lesson 5, the effect of dams on the river and local ecosystem health including water temperature and seasonal flooding; lesson 6, salmon life cycle and dam accommodations to aid fish migration; lesson 7, the water cycle, especially evaporation; and lesson 8, dam maintenance, lifespan, failure and removal.

Dams are impressive engineering achievements, providing countless ways to apply an understanding of science and math concepts (including potential and kinetic energy, Pascal's Law, water pressure, gravity, forces) to creating unique structures that provide many benefits to people. Dams have many functions: to divert and control a water supply to prevent floods; to store water for irrigation and during droughts; to generate electricity, and to provide navigable waters. All types of engineers cooperate to design dams; they consider an array of variables that range from environmental impact to amount of energy generation to river navigation via locks, working with community planners to balance competing demands to create the most effective and useful designs. Engineers calculate the forces expected to act on a dam's structure, taking into consideration different geometries and materials, and the most suitable size and type for its planned purpose and surroundings. Increasingly, engineers are understanding the disturbances dams cause to surrounding ecosystems, and are finding new ways to mitigate ecological disruption. In addition to designing dams, engineers oversee their long-term reliability and maintenance, learning from any failures, and sometimes recommend their removal.