Laserfiche WebLink
These tests would also provide data on pumping water levels that occur in the South Platte River <br />basin. Only a portion of the production wells needs to be tested. This is due to inherent <br />similarities between wells producing from similar aquifers in similar locations. The number of <br />wells to be tested for purposes of estimating wire to water efficiencies would be determined in the <br />feasibility study. However, water to wire efficiencies could be greatly affected by the piping <br />design of individual well systems, making accurate determination of rating curves a difficult task. <br />Obtaining well rating curves would involve (1) mapping of wells using the data provided from <br />the GIS consultant, (2) identifying those wells that have accessible power records, (3) identifying <br />those wells to be tested in order to determine wire to water efficiency, and (4) running the <br />necessary tests. <br />Up to approximately 150 wells out of the estimated 5,700 wells with greater than 500 gpm <br />capacities would be tested. Using a subset of wells would provide information to allow <br />extrapolation of the Arkansas River Basin wire to water efficiency data to wells in the South <br />Platte River basin. This would allow testing of wells to determine well/pump efficiencies for <br />wells in all geographic regions, including the Lower South Platte Alluvium Region, Denver <br />Basin and Overlying Alluvium Region, North Park and South Park Region, and the Other <br />Designated Groundwater Basins. <br />3.8.3.5 Task 5-Calculate Pumping from Consumptive Use Estimates. Under this task, <br />the groundwater contractor would work closely with the consumptive use contractor to obtain crop <br />irrigation requirement data, irrigation surface water supply data, irrigation efficiency data and other <br />necessary data needed for the consumptive-use based calculations to estimate groundwater <br />pumping. <br />3.8.3.6 Task 6-Develop Pumping Estimates from Collected Data. Under this task, <br />estimates of well pumping would be made based on the collected data. These estimated values <br />would then be compared to historical well pumping where possible for calibration purposes. <br />3.9 GEOLOGIC STRUCTURE AND AQUIFER PROPERTIES <br />Figure 3-1 at the end of this chapter shows the aquifers in the South Platte River basin. Geologic <br />structure (aquifer extent and thickness) of all aquifers in the basin will be used to identify the <br />horizontal and vertical extent of the various aquifers in the study area. Aquifer properties <br />describe the groundwater flow rate and yield and include parameters such as hydraulic <br />conductivity, storage coefficient, transmissivity, streambed conductance (used to simulate <br />stream-aquifer interactions) and saturated thickness. The geologic structure and aquifer property <br />information are necessary inputs in groundwater models. These models will be used to estimate <br />drawdown due to pumping, groundwater levels, flow within and between aquifer layers, aquifer <br />yield and stream-aquifer relationships. <br />p:data\gen\spdss~final report\chapter 3.doc 3 -22 <br />October 31, 2001 <br />