From abstract: During fiscal years 1978 through 1981, the U.S. Geological Survey contracted for the acquisition and analysis of hydrologic data from 104 surface water stations, 26 ground water stations, and 15 precipitation gages as well as for several hundred miscellaneous surface water measurements of flow and water quality. The work was performed in Montana, North Dakota, Wyoming, Utah, New Mexico, and Oklahoma, terminating at the end of the fiscal year 1981. This report is an assessment of this contracting effort from the standpoint of cost and of quality control measures employed to ensure an acceptable product.

From introduction: This report describes the results of an investigation in which three computer models were used to evaluate different levels of the proposed reservoir development. One model simulated streamflow conditions with alternative multireservoir configurations; a second model simulated the dissolved-solids concentrations at various locations in the basin; and a third model used streamflows and dissolved solids concentrations to simulate the water-quality conditions within certain proposed reservoirs. This study was designed to demonstrate the application of computer-modeling techniques in evaluating impacts of proposed reservoirs.

From introduction: The overall purpose of this study were twofold: (1) To determine where greatest yielding wells at shallowest depths would produce water of suitable quality for municipal and industrial supplies; and (2) to determine regional effects of additional water development on the hydrologic system.

From abstract: "A digital model was used to simulate ground-water flow within the Bates Creek alluvial aquifer, southwest of Casper, Wyoming. Hydrologic data was collected during 1977 and 1978 were used to develop the flow model under steady-state and transient. Three scenarios for operating the stream-aquifer system were evaluated with the digital model." It contains maps, graphs, and tables.

Purpose and scope: The purpose of this investigation was to: (1) Determine the extent of present ground-water development for irrigation, industrial, and municipal use and describe the effect of this development on water levels in the separate aquifers; and (2) determine the net result of imported surface water and pumpage on water levels and stream discharge in the area.

Abstract: This report is a supplement to the report, "Effect of pumpage on ground-water levels as modeled in Laramie County, Wyoming," published as U.S. Geological Survey Water-Resources Investigations Open-File Report 80-1104 which describes ground-water conditions in post-Cretaceous rocks in Laramie County. The computer program and the data used to model ground-water conditions in post-Cretaceous rocks in Laramie County are listed in this report.

From introduction: This report describes the results of 1980 sampling of ground-water pumpage for irrigation on the High Plains, one phase of the High Plains Regional Aquifer-System Analysis project. These data were collected to estimate the volume of irrigation water pumped during 1980 and to determine current trends in irrigation pumpage on the High Plains.

From purpose and scope: This study estimates the time and spatial distribution of ground-water-level declines and streamflow depletions that may have been expected to occur within the vicinity of Muleshoe Flat as a result of the proposed irrigation development. A hydrogeologic reconnaissance of the study area was undertaken to define the ground-water-flow system and to collect pertinent hydrologic and geologic data.

Abstract: Water shortages are expected in the Upper Colorado River Basin because of increasing water demands for various uses. Ground-water supplies can help to reduce water shortages but ground-water reservoirs have not been studied in detail. The regional aquifer systems analysis of the Upper Colorado River Basin is a study of the major ground-water resources of the region. Aquifers occur in the sedimentary rock sequences in basins and uplifted regions, in volcanic-rock regions, and in stream-valley alluvium. The project work will include collection and compilation of existing geologic, geophysical, hydrologic, and geochemical data. These data will be used to assess the hydrologic characteristics of the aquifer systems and to estimate the hydrologic effects of discharge from, or recharge to, selected aquifers.