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Garrison Dam, the world's fifth-largest earthen dam at over 2 miles long and half a mile wide, controls the Missouri River and holds back Lake Sakakawea, the nation's third-largest reservoir. Completed in the 1950s, it has a storage capacity of 66.5 million cubic yards of earth and 1.5 million cubic yards of concrete, costing approximately $3.6 billion in 2025 dollars.

In contrast, the Fargo-Moorhead Area Diversion, set for substantial completion in 2026, features a 30-mile channel and a 22-mile embankment, excavating over 55.8 million cubic yards of earth at a cost of $3.2 billion. While Garrison Dam provides multiple services including hydropower and recreation, the diversion focuses solely on flood control for the Fargo-Moorhead area.

The two projects differ significantly in discharge capacity; Garrison can release up to 827,000 cubic feet per second, while the diversion can handle 20,000 cubic feet per second during floods. The diversion represents a public-private partnership involving local governments and construction firms.