Garrison Dam


The Garrison Dam is one of the largest earth-filled dams in the world that is used for irrigation and power generation. It is 2.5 miles long and 210 feet high, tapering from a half-mile wide at its base to 60 feet at its summit. Built by the U.S. Army Corps of Engineers in 1947-54, it is one of six dams built on the Missouri River to control recurrent flooding. During an average year, the powerplant's give generating units produce 2,600,000 megawatt hours of electricity. The water released through the 28-gate spillway can attain a speed of 75 mph.

Activity Details

Activity Type:Trips and Destinations
Discipline:Civil
Topic(s):Electricity
Grade:K-2, 3-5, 6-8, 9-12
Time:Full day

Fun Fact:Some 66.5 million cubic yards of dirt, equal to 9 million truckloads, and 1.5 million cubic yards of concrete were used to build the Garrison Dam. The dam's reservoir, Lake Sakakawea, has a shoreline of 1,350 miles, making it the third-largest reservoir by storage volume in the U.S.