2020 Map of Lewis Reservoir

About this map

Fort Peck Lake dominates the eastern edge of this landscape in Valley County, Montana, where the rugged Missouri River breaks transition into a network of upland coulees and ridges. The terrain is defined by a complex system of managed water resources, featuring numerous small impoundments such as Lewis Reservoir, Willow Flat Reservoir, and Langen Reservoir scattered across the high plains. These reservoirs, often named for local families or landmarks like the Lost McMenomey Reservoir, reflect the essential infrastructure required for ranching in this arid environment. The map details a series of prominent geographic features including Bomber Coulee, Skunk Coulee, and a progression of numbered landmarks from Second Ridge to Fifth Ridge. Access to this remote area is primarily via unpaved routes such as Willow Creek Rd and The Pines Rd, which navigate the high ground between deep drainage systems.