1966 Map of Rock Island Dam

About this map

Rock Island Dam stands as the central engineering marvel of this mid-1960s survey, anchoring the Columbia River between Chelan and Douglas counties. This industrial corridor is defined by the massive infrastructure required for hydroelectric power, including a Powerhouse, a Fish Ladder, and specialized installations like the Valhala Substation and Columbia Substation. The settlement of Voltage sits adjacent to the dam, while the Great Northern railroad tracks follow the eastern bank, passing through the small siding of Bonspur. Away from the river, the landscape shifts abruptly to the dramatic geology of Badger Mountain and the deep trench of Moses Coulee. Land use is further delineated by the Rock Island State Park and the Colockum Game Range Headquarters to the south, highlighting a region balanced between heavy utility production and conservation.