2023 Map of Grassy Mountain

About this map

Grassy Mtn and the surrounding high desert of Malheur County define this landscape, where water management is central to the terrain. A network of man-made catchments, including Grassy Mountain Reservoir, North Grassy Mountain Reservoir, and Schweizer Reservoir, are scattered across the high draws. These features, along with Government Corral Spring and Sagebrush Spring, reflect the necessities of ranching and livestock management in a semi-arid environment. To the southeast, the terrain drops toward the Owyhee River and the northern reaches of Lake Owyhee, which are accessed by the winding Owyhee Lake Rd. The map also details prominent geological landmarks such as Shell Rock Butte and Haystack Rock, alongside drainage systems like Sand Hollow Creek and Lone Willow Creek. This survey captures the specialized infrastructure of eastern Oregon, where isolated springs and reservoirs provide the essential lifeblood for the vast basin and range country.