2024 Map of Garrison Dam South

About this map

The Missouri River carves a deep valley through the high plains of Mercer and McLean counties, controlled at the northern edge of this survey by the massive infrastructure of the Garrison Dam National Fish Hatchery. The settlement of Riverdale sits overlooking the banks of Lake Sakakawea, reflecting the modern development and conservation efforts that have redefined this stretch of the river. Farther downstream, the cultural heritage of the landscape is preserved within the Knife River Indian Villages National Historic Site, where the terrain begins to transition from the engineering of the dam to more traditional prairie drainages.