Lesson Plan

Freeing the Elwha (Effects of the Elwha River Dams)

The Elwha Dam.


What combination of factors (both natural and man-made) is necessary for healthy river restoration and how does this enhance the sustainability of natural and human communities?


This lesson focuses on the impacts that the building of the two dams on the Elwha River had on anadromous fish species, including the loss of 70 miles of river habitat for migrating fish, the effects of sediment loss on spawning grounds downstream, and general habitat degradation downstream. Learn about pre-dam conditions both in-river and in the surrounding terrestrial environment. Then hear the story of Thomas Aldwell, the entrepreneur who built the first dam and refused to accommodate fish. Finally, discuss the political and environmental conditions that led to the decision to remove the dams.

  • Watershed:The drainage basin where all precipitation (snow and rain) on the surface or below ground, drains into a single river or lake on the way to the ocean or to an endorheic basin.
  • Dam: A barrier constructed across a waterway to control the flow or raise the level of water.
  • Reservoir: A man-made water containment system often the result of lake filling behind a dam, but also can be water stored in large tanks or underground storage.
  • Anadromous: (uh-nad-ruh-muh s) A fish that is born in freshwater, migrates to the ocean to spend its adult life, and returns to freshwater to spawn. 


  • Lesson 15- Effects of the Elwha River Dams.pptx
  • Access to computers.
  • Student page (printable handout - 2pages)
  • Reflection Journal pages (printable handout)


Review Essential Question; introduce Guiding Question.

Students should take a few minutes to respond to the first reflection prompts. Discuss their answers and any questions they've generated.
Present the PowerPoint Lesson.
Refer to readings (web sites below) and the PowerPoint Lesson to have students prepare newspaper articles on the building of the dams, the effect on salmon and finally the removal of the dams:
http://www.historylink.org/ index.cfm?DisplayPage=output. cfm&file_id=7590 
Have students use the following web site to build then publish their article(s) http://interactives.mped.org/view_interactive.aspx?id=110&title
Hand out the second Reflection Journal Page. Give students time for a final reflection the lesson.


Reflection journal (rubric attached)
Newspaper article rubric (Attached)