Grand Coulee Dam is the hydroelectric power plant developed on Columbia River in Washington State of United States. It is the largest hydroelectric power plant in US. The lake formed by the reservoir of Grand Coulee Dam has been given name Franklin Delano Roosevelt Lake, after the US president who presided over the construction of the dam.
The total length of Grand Coulee Dam is 1586 meters and its height is 168 meters, which is more than the height of Grand Pyramid of Giza. The hydraulic height of the Grand Coulee Dam is 115 meters, which is twice the height of Niagara Falls. The total width of the spillway is 168 meters. The total amount of the concrete used in the construction of Grand Coulee Dam is good enough to construct a sidewalk of four feet wide and four inch deep around the whole equator twice.
The construction work on Grand Coulee Dam started in the year 1933. During construction the design was changed so that more people can be employed, more power can be generated and wider areas can be irrigated. Work had to be stopped for many years due to Second World War and other reasons. The work on Grand Coulee hydroelectric power plants was completed in the year 1980 with the total power generation capacity of 6809 MW. Grand Coulee is the gravity type of hydroelectric power plant.

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