2024 Map of Grasmere Reservoir

About this map

Grasmere Reservoir and its surrounding high-desert plateau define this section of Owyhee County, where water sources are critical landmarks. The landscape is marked by a series of drainages and springs, including Crab Creek, Louse Creek, and the isolated Roll Inn Spring. Higher elevations are represented by the prominent flat-topped Little Blue Table and the Rattlesnake Basin, which guide the flow of seasonal waterways toward the Rattlesnake Reservoir. The area’s aviation history and ranching infrastructure are noted through the presence of the Grasmere Airport and several remote roadways like Rowland Rt Rd and Mt Creek Rd. This modern survey illustrates how traditional landmarks, from Timber Draw to Marys Creek, continue to orient travelers across this expansive Idaho backcountry.