Date of this Version
From: Soil Survey of Garden County, Nebraska (1999). By Jay R. Wilson, A. Tyler Labenz, Renee D. Gross, Glenn A. Borchers, Steven A. Scheinost, Charles F. Mahnke, Daniel R. Shurtliff, David R. Hoover, Arthur VOigtlander, and Alan J. Steube, Natural Resources Conservation Service; and Randy Kowalski, Stephen L. Hartung, and Neal B. Stolpe, University of Nebraska, Conservation and Survey Division; United States Department of Agriculture, Natural Resources Conservation Service, in cooperation with the University of Nebraska, Conservation and Survey Division.
All of Garden County is underlain by the Brule Formation. This formation is tightly cemented and yields sufficient water to wells only in areas where the siltstone has been fractured. In most places the Brule Formation forms an impermeable seal that prevents water from moving downward from the overlying aquifers. The Arikaree Group is unimportant as an aquifer in the county, but the younger Ash Hollow Formation is important, particularly beneath the Cheyenne Tableland. Most, if not all, of the domestic and livestock wells on the tableland tap this aquifer. The thickness of the Ash Hollow Formation is 100 feet or less beneath much of the tableland except in the southeastern part of the county in the Ash Hollow Creek area, where it is more than 200 feet thick, and in the southwestern part of the county in the Rush Creek area, where it is more than 300 feet thick. In most of the area of the Cheyenne Tableland, the supply of ground water is adequate for domestic and livestock watering needs but not for irrigation. The Ash Hollow Formation is more than 700 feet thick in the northeastern part of the county beneath the Sandhills and contains an abundant supply of water. It has not been used extensively as a source of water because the overlying younger deposits also contain an abundant supply of water.