People and Planet - Don't Dam It!
For over a hundred years in the Pacific Northwest, the Elwha freshwater ecosystem was being disturbed by the Elwha dam. Salmon that typically spawn upstream were not able to do so.
Watch this 4:39 minute video clip titled “Restoring the Elwha”
- How were the salmon being affected by the dam?
- By simply removing the dam, will the ecosystem improve? What will change?
- Hydoelectric power, a renewable energy source with no pollution, is an excellent alternative to fossil fuels. Removing the dam means removing a good source of power. How was the dam threatening the survival of salmon? Go to http://www.nmfs.noaa.gov/pr/species/fish/salmon.htm for more information about the impact on salmon. Are there other threats to the survival of the salmon in the Pacific Northwest?
- How will the shape of the river change as the dam is removed? How will incorporating log jams improve areas for salmon to spawn? Build a model or use a stream table to simulate the Elwha river with the dam and without the dam. Add log jams. Observe the velocity of stream flow and locations of sediment deposition.
Answers - Highlight the box below to see the answers.
Source: Open Education Group Textbooks - Earth Science