|Fig. 1: The Grand Coulee Dam (Source: Wikimedia Commons)|
Located on the Columbia River in the state of Washington, the Grand Coulee Dam stands 550 feet tall and spans across 5,223 feet of river.  Constructed in 1941, the dam was built to harness the immense power of the Columbia River and turn this into electrical power supply. Fig. 1 shows the Grand Coulee Dam today. The Grand Coulee Dam has had many positive and negative economic, environmental, social, and cultural impacts in the immediate and surrounding areas of the dam.
The main impact the Grand Coulee Dam has had is providing a renewable source of clean energy. The hydraulic turbines within the dam extract 94 percent of the power of a falling current of water.  This massive source of energy also helped to decrease costs of electricity in the surrounding areas. The Grand Coulee Dam also created many jobs. People were employed to construct the dam and then to work on and maintain the dam after it was completed.  The dam revolutionized the Pacific Northwest, and played a key part in attracting people to the area.  For example, farmers moved onto reclaimed land and used water from the dams reservoir to irrigate their crops. 
The Grand Coulee Dam has also had many negative impacts. The dam disrupts fish migrations and has contributed to the massive decline in Columbia salmon populations. The annual catch of Columbia salmon has declined from 33.9 million pounds in 1930 to just 1.4 million pounds in 1993.  The National Oceanic and Atmospheric Administration notes the struggling Columbia Salmon population in their '2016 Five Year Status Review' and outlines future plans to influence Salmon returns in coming years. [1,3] The declining Salmon population has largely affected Native American tribes in the area, who have fished the Columbia for hundreds of years. The natives have also been forced out of much of their original lands to make way for farmers and new settlers over time.  The Grand Coulee Dams negative impacts have proven costly, and billions of dollars have been spent to try to rectify these negative impacts. For example, over $1 billion has been contributed to trying to rectify the salmon situation caused by the dam. 
The Grand Coulee Dam was built to supply clean, renewable energy to the Pacific Northwest and it has accomplished that goal. However, the dam also had many unintended negative impacts on the area. Hopefully we can learn from the case of the Grand Coulee Dam and consider all the possible effects future dams could have.
Collin Riccitelli. The author warrants that the work is the author's own and that Stanford University provided no input other than typesetting and referencing guidelines. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
 C. Chandler II, "The Grand Coulee Dam," Physics 240, Stanford University, Fall 15.
 R. White, The Organic Machine (Hill and Wang, 1995).
 D. D. Dauble and D. G. Watson, "Status of Fall Chinook Salmon Populations in the Mid-Columbia River, 1948-1992," N. Am. J. Fish. Manage. 17, 283 (1997).