By Mark Skiles
This activity will help you understand
- why dams have been built in Nebraska to create reservoirs
- what factors must be considered when building a dam and
- how to design and build a dam yourself!
- colored pencils
- Snake River Drainage Map
- graph paper
Many dams in Nebraska have been built to control flooding. By building a dam, a reservoir of water is created that holds pooled water behind it. The rate and amount of water flow released can be regulated by opening and closing special gates on the dam. In this way, flooding can be controlled and a reservoir of water can be created to be used by humans (irrigation, recreation etc.).
- Using a blank piece of graph paper and a pencil, trace over the Snake River Drainage Map so you have two copies. You will do all drawing and coloring on the map copy you have traced.
- In general, the overall flow of water on your map is in what direction?__________ Pick a location on your map to place the dam and then draw it using a black pencil. Remember, the dam must be in a location where it can collect water from all Snake River tributaries as well. The elevation of the top of the dam must be 2700 ft. above sea level.
- Your reservoir is designed to hold water up to 2500 ft. above sea level. If it were to exceed this elevation, flood-gates would be opened and water released. Using a red pencil, outline the contour line that would represent the high water mark in
- Label the dam and spillway (where the water exits the reservoir and returns to the river).
- If any houses are located so they may be inundated by water as the reservoir fills, they must be moved. Relocate houses by moving them the shortest distance possible to an elevation at or above 2750 ft. Redraw them at the location you have chosen.
- Using a brown pencil, shade in any areas below the dam where new farmland would be created.
- Using a green pencil, design 2 new recreational areas that include necessary public facilities (beaches, restrooms, boat docks, parking lots etc.)
- Using a blue pencil, draw a highway that goes across the dam and circles the reservoir. Be sure to connect the recreation areas and the town with this highway.
- Answer questions on next page.
- How many acres of land are covered by the reservoir?_______________
- How many houses must be relocated?_______________
- How many total miles of highway will you create? (use distance scale provided)_______________
- Approximately how many acres of new farmland will be created?_______________
- Describe all of the positive aspects of creating the reservoir.
- Describe all of the negative aspects of creating the reservoir.
- List all of the possibilities for generating money with the new reservoir.