Supplemental water-level change data used to substantiate the map of water-level changes in the High Plains aquifer, predevelopment (about 1950) to 2017

The High Plains aquifer extends from about 32 degrees to almost 44 degrees north latitude and from about 96 degrees 30 minutes to 106 degrees west longitude. The aquifer underlies about 175,000 square miles in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. This digital data set consists of three sets of water-level measurements. The first set are the supplemental water-level measurements for 457 wells screened in the High Plains aquifer, not located in New Mexico  , and measured in predevelopment, and between 2013 and 2016, but not in 2017. These supplemental measurements were used to calculate historical water-level change values for predevelopment to 2013 to 2016 and approximate water-level change values from predevelopment to 2017 to substantiate the map of water-level changes, predevelopment (about 1950) to 2017. The water-level measurements used to calculate historical water-level changes from predevelopment are (1) 223 wells measured in predevelopment and in 2016, but not measured in 2017, which are used to calculate water-level change, predevelopment to 2016, (2) 83 wells measured in predevelopment and in 2015, but not measured in 2016 or 2017, which are used to calculate water-level change, predevelopment to 2015, (3) 86 wells measured in predevelopment and in 2014, but not measured in 2015, 2016, or 2017, which are used to calculate water-level change, predevelopment to 2014, and (4) 65 wells measured in predevelopment and in 2013, but not measured in 2014, 2015, 2016, or 2017, which are used to calculate water-level change, predevelopment to 2013. Two additional sets of water-level measurements were used to approximate water-level change, predevelopment to 2017, but did not have predevelopment water-level measurements. The first set included 296 wells, which were located in areas where water level declines from predevelopment to 1980 were 50 feet or more (Luckey and others, 1981; Cederstrand and Becker, 1999) and were measured in 1980 and in 2017, but not measured in the predevelopment period. For these wells, approximate water-level changes, predevelopment to 2017, were calculated as the beginning contour interval from the map of water-level change, predevelopment to 1980, plus measured water-level change from 1980 to 2017. The second set of water-level measurements used to calculate approximate water-level changes were from 1,134 wells that were measured on or before 6/15/1978 (termed post-development) and in 2017, but not in the predevelopment period. For these wells, approximate water-level changes, predevelopment to 2017, were calculated as the water level, 2017, minus water level, post-development.

Tags: aquifers, biota, colorado, contouring, geoscientificinformation, geospatial-analysis, great-plains, groundwater, groundwater-level, high-plains, high-plains-aquifer, hydrogeology, kansas, nebraska, new-mexico, ogallala-aquifer, oklahoma, south-dakota, texas, usgs-61395e89d34e40dd9c0dcbab, water-level-change, wyoming
Organization: Department of the Interior