6.4 SAND WASH BASIN
The Sand Wash Basin of northwestern Colorado straddles the Wyoming state line between the Park Range on the east and the Uinta uplift on the west. It is located within the northeastern half of Moffat County and western two-thirds of Routt County, as well as a small section of northeastern Rio Blanco County and the northern tip of Garfield County. The Sand Wash Basin is part of the Wyoming Basin physiographic province and the Colorado portion encompasses approximately 4,760 square miles (Figure 6.4-1).
Most of the basin is a rolling plain with elevations above 6,000 feet, although the eastern part of the basin grades into foothills and mountains with elevations above 10,000 feet. The Yampa River and its tributary, the Little Snake River, flow into the Green River, and represent the principal surface drainage systems for the basin. Administration of water within the Sand Wash Basin is under the jurisdiction of Water Division 6, located in Steamboat Springs.
This portion of Colorado is sparsely populated. The Colorado Division of Water Resources well permit database indicates that there are approximately 2,157 bedrock aquifer wells of record in the Sand Wash Basin. The majority of which are concentrated around the major population centers of Craig and Steamboat Springs.