Groundwater potentiometric-surface contours for spring 2022 (April 4 to 8, 2022) and autumn 2022 (October 30 to November 4, 2022) were created for the alluvial aquifer in Big Lost River Valley. The well numbers and station names used to create the potentiometric-surface contours and groundwater-level change maps are provided in this data release. The location, depth to water, and potentiometric-surface altitude for these wells can be accessed on USGS National Water Information System (NWIS) or Idaho Department of Water Resources (IDWR) groundwater portal. The interpreted 20-foot contours of the potentiometric-surface are also provided in this data release. The contours are referenced to the North American Vertical Datum of 1988 (NAVD 88). The potentiometric-surface contours are divided into three water-bearing units - shallow, intermediate, and deep - based on well depth, potentiometric-surface altitude, and hydrogeologic unit. The intermediate and deep units were only identified in the southern portion of the valley near Arco, Idaho. The potentiometric-surface contours ranged from 4,900 to 6,660 feet above NAVD 88. The groundwater-level change at well sites from spring to autumn 2022, spring to autumn 1968, spring 1968 to spring 2022, spring 1991 to spring 2022, and spring 1968 to spring 1991 were calculated and are provided in a shapefile.

Groundwater potentiometric-surface contours for spring 2022 (April 4 to 8, 2022) and autumn 2022 (October 30 to November 4, 2022) were created for the alluvial aquifer in Big Lost River Valley. The well numbers and station names used to create the potentiometric-surface contours and groundwater-level change maps are provided in this data release. The location, depth to water, and potentiometric-surface altitude for these wells can be accessed on USGS National Water Information System (NWIS) or Idaho Department of Water Resources (IDWR) groundwater portal. The interpreted 20-foot contours of the potentiometric-surface are also provided in this data release. The contours are referenced to the North American Vertical Datum of 1988 (NAVD 88). The potentiometric-surface contours are divided into three water-bearing units - shallow, intermediate, and deep - based on well depth, potentiometric-surface altitude, and hydrogeologic unit. The intermediate and deep units were only identified in the southern portion of the valley near Arco, Idaho. The potentiometric-surface contours ranged from 4,900 to 6,660 feet above NAVD 88. The groundwater-level change at well sites from spring to autumn 2022, spring to autumn 1968, spring 1968 to spring 2022, spring 1991 to spring 2022, and spring 1968 to spring 1991 were calculated and are provided in a shapefile.

Groundwater in the arid Mountain Home area is vital to agricultural, municipal, industrial and other water users who are concerned about declining groundwater levels. The U.S. Geological Survey, in cooperation with the Idaho Department of Water Resources, developed a hydrogeologic framework to provide a conceptual understanding of groundwater resources in the Mountain Home area. As part of the hydrogeologic framework, a digital borehole database was compiled and used to generate a three-dimensional hydrogeologic framework model to represent the distribution and thickness of five hydrogeologic units: granite, rhyolite, basalt, fine-grained sediments, and coarse-grained sediments. The digital borehole database was compiled from existing data; it contains borehole location, lithology, construction, and groundwater-level data for 540 boreholes in the Mountain Home area. A gridded dataset representing the surficial distribution of hydrogeologic units, derived from the statewide geologic map, was also developed to fill gaps in the spatial distribution of boreholes. The three-dimensional hydrogeologic framework model of the Mountain Home area was generated from the borehole database and surficial hydrogeologic units, and an animation showing the model cut-away in successive slices was created. More information on digital borehole information, surficial hydrogeology, model construction, and limitations can be found in the companion report, SIR 2024-5132 (Hydrogeologic framework of the Mountain Home area, southern Idaho by L.M. Zinsser and S.D. Ducar).

The High Plains aquifer extends from approximately 32 to 44 degrees north latitude and from 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 dataset contains water-level measurements from wells screened in the High Plains aquifer and measured in both predevelopment (about 1950) and for 2019. There were 2,741 wells measured in both predevelopment (about 1950) and 2019 as well as 71 wells located in New Mexico, which were measured in predevelopment and at least once between 2015 and 2018. These water-level measurements were used to map water-level changes, predevelopment (about 1950) to 2019. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.

The High Plains aquifer extends from approximately 32 to 44 degrees north latitude and from 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 dataset contains water-level measurements from wells screened in the High Plains aquifer and measured in both predevelopment (about 1950) and for 2019. There were 2,741 wells measured in both predevelopment (about 1950) and 2019 as well as 71 wells located in New Mexico, which were measured in predevelopment and at least once between 2015 and 2018. These water-level measurements were used to map water-level changes, predevelopment (about 1950) to 2019. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.

The High Plains aquifer extends from approximately 32 to 44 degrees north latitude and from 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 dataset contains water-level measurements from wells screened in the High Plains aquifer and measured in both predevelopment (about 1950) and for 2019. There were 2,741 wells measured in both predevelopment (about 1950) and 2019 as well as 71 wells located in New Mexico, which were measured in predevelopment and at least once between 2015 and 2018. These water-level measurements were used to map water-level changes, predevelopment (about 1950) to 2019. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.

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 dataset is comprised of water-level measurements from 7,195 wells measured in both 2017 and 2019, which were used to map water-level changes, 2017 to 2019. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.

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 dataset is comprised of water-level measurements from 7,195 wells measured in both 2017 and 2019, which were used to map water-level changes, 2017 to 2019. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.

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 dataset consists of three sets of water-level measurements. The first set are the supplemental water-level measurements for 547 wells screened in the High Plains aquifer, not located in New Mexico, measured in predevelopment and at least once for 2015 through 2018, but not for 2019. These supplemental measurements were used to calculate historical water-level change values for predevelopment to 2015 to 2018 and approximate water-level change values from predevelopment to 2019 to substantiate the map of water-level changes, predevelopment (about 1950) to 2019 (figure 1 in https://doi.org/10.3133/sir20235143). The water-level measurements used to calculate historical water-level changes from predevelopment are (1) 218 wells measured in predevelopment and in 2018, but not measured in 2019, which are used to calculate water-level change, predevelopment to 2018, (2) 152 wells measured in predevelopment and in 2017, but not measured in 2018 or 2019, which are used to calculate water-level change, predevelopment to 2017, (3) 117 wells measured in predevelopment and in 2016, but not measured in 2017, 2018, or 2019, which are used to calculate water-level change, predevelopment to 2016, and (4) 60 wells measured in predevelopment and in 2015, but not measured in 2016, 2017, 2018, or 2019, which are used to calculate water-level change, predevelopment to 2015. The second and third sets of water-level measurements were used to approximate water-level change, predevelopment to 2019, but did not have predevelopment water-level measurements. The second set included 292 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 2019, but not measured in the predevelopment period. For these wells, approximate water-level changes, predevelopment to 2019, were calculated as the starting value of the polygon range (for example 50 ft for the polygon of declines from 50 to 75 ft) from the map of water-level change, predevelopment to 1980, plus measured water-level change from 1980 to 2019. The third set of water-level measurements used to calculate approximate water-level changes were from 1,213 wells that were measured on or before 6/15/1978 (termed post-development) and in 2019, but not in the predevelopment period. For these wells, approximate water-level changes, predevelopment to 2019, were calculated as the water level, 2019, minus water level, post-development.

The High Plains aquifer extends from south of 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 contains the water-level measurements from 3,092 wells measured in both predevelopment (about 1950) and 2015 and from 72 wells, which are located in New Mexico and Wyoming and were measured in predevelopment and at least one time from 2011 to 2014. These water-level measurements were used to map water-level changes, predevelopment (about 1950) to 2015. The map was reviewed for consistency with the relevant data at a scale of 1:1,000,000.