Effect of pumpage on ground-water levels as modeled in Laramie County, Wyoming

Open-File Report 80-1104



Groundwater is being extensively developed for domestic, agricultural, and industrial use in a 2,320-square mile area in Laramie County, WY., bounded approximately by Horse Creek on the north, Nebraska on the east, Colorado on the south, and pre-Tertiary outcrops on the west. Currently (1977) about 47,300 acres of land are irrigated with groundwater. Groundwater levels are declining in some areas as much as 4 feet per year. The investigation was made to provide State water administrators with data on water-level changes resulting from present (1977) groundwater withdrawals and to provide a means of predicting the future effect of groundwater development. A digital model was developed of the hydrologic system in the post-Cretaceous rocks. The ability of the model to simulate the hydrologic system was determined by comparing the water-level changes measured at 37 observation wells located in areas of irrigation pumping with the water-level changes calculated by the model for 1971-77. Comparison of the measured and calculated changes showed agreement with a root-mean-square deviation of + or - 3.6 feet with 8 feet as the maximum deviation. It is concluded that the model adequately simulates present hydrologic conditions in the post-Cretaceous rocks and may be used to predict the effect of applied stress to the system. (USGS)
Publication type Report
Publication Subtype USGS Numbered Series
Title Effect of pumpage on ground-water levels as modeled in Laramie County, Wyoming
Series title Open-File Report
Series number 80-1104
DOI 10.3133/ofr801104
Edition WRI/OFR
Year Published 1980
Language ENGLISH
Publisher U.S. Dept. of the Interior, Geological Survey,
Contributing office(s) WY-MT Water Science Center
Description v, 31 p. ill., maps ;28 cm.
Google Analytic Metrics Metrics page
Additional publication details