This dataset contains 50-ft contours for the Hot Springs shallowest unit of the Ouachita Mountains aquifer system potentiometric-surface map. The potentiometric-surface shows altitude at which the water level would have risen in tightly-cased wells and represents synoptic conditions during the summer of 2017. Contours were constructed from 59 water-level measurements measured in selected wells (locations in the well point dataset). Major streams and creeks were selected in the study area from the USGS National Hydrography Dataset (U.S. Geological Survey, 2017), and the spring point dataset with 18 spring altitudes calculated from 10-meter digital elevation model (DEM) data (U.S. Geological Survey, 2015; U.S. Geological Survey, 2016). After collecting, processing, and plotting the data, a potentiometric surface was generated using the interpolation method Topo to Raster in ArcMap 10.5 (Esri, 2017a). This tool is specifically designed for the creation of digital elevation models and imposes constraints that ensure a connected drainage structure and a correct representation of the surface from the provided contour data (Esri, 2017a). Once the raster surface was created, 50-ft contour interval were generated using Contour (Spatial Analyst), a spatial analyst tool (available through ArcGIS 3D Analyst toolbox) that creates a line-feature class of contours (isolines) from the raster surface (Esri, 2017b). The Topo to Raster and contouring done by ArcMap 10.5 is a rapid way to interpolate data, but computer programs do not account for hydrologic connections between groundwater and surface water. For this reason, some contours were manually adjusted based on topographical influence, a comparison with the potentiometric surface of Kresse and Hays (2009), and data-point water-level altitudes to more accurately represent the potentiometric surface. Select References: Esri, 2017a, How Topo to Raster works—Help | ArcGIS Desktop, accessed December 5, 2017, at ArcGIS Pro at http://pro.arcgis.com/en/pro-app/tool-reference/3d-analyst/how-topo-to-raster-works.htm. Esri, 2017b, Contour—Help | ArcGIS Desktop, accessed December 5, 2017, at ArcGIS Pro Raster Surface toolset at http://pro.arcgis.com/en/pro-app/tool-reference/3d-analyst/contour.htm. Kresse, T.M., and Hays, P.D., 2009, Geochemistry, Comparative Analysis, and Physical and Chemical Characteristics of the Thermal Waters East of Hot Springs National Park, Arkansas, 2006-09: U.S. Geological Survey 2009–5263, 48 p., accessed November 28, 2017, at https://pubs.usgs.gov/sir/2009/5263/. U.S. Geological Survey, 2015, USGS NED 1 arc-second n35w094 1 x 1 degree ArcGrid 2015, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html. U.S. Geological Survey, 2016, USGS NED 1 arc-second n35w093 1 x 1 degree ArcGrid 2016, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html.

This dataset consists of altitudes of 18 springs located throughout the study area which were used in construction of the potentiometric-surface map. Springs were selected from the previously published report by Kresse and Hays (2009), and site reconnaissance. Surface-water features and springs represent the intersection of the groundwater-table with land surface. Spring altitudes were calculated from 10-meter digital elevation model (DEM) data (U.S. Geological Survey, 2015; U.S. Geological Survey, 2016) . References: Kresse, T.M., and Hays, P.D., 2009, Geochemistry, Comparative Analysis, and Physical and Chemical Characteristics of the Thermal Waters East of Hot Springs National Park, Arkansas, 2006-09: U.S. Geological Survey 2009–5263, 48 p., accessed November 28, 2017, at https://pubs.usgs.gov/sir/2009/5263/. U.S. Geological Survey, 2015, USGS NED 1 arc-second n35w094 1 x 1 degree ArcGrid 2015, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html. U.S. Geological Survey, 2016, USGS NED 1 arc-second n35w093 1 x 1 degree ArcGrid 2016, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html.

This dataset consists of altitudes of 18 springs located throughout the study area which were used in construction of the potentiometric-surface map. Springs were selected from the previously published report by Kresse and Hays (2009), and site reconnaissance. Surface-water features and springs represent the intersection of the groundwater-table with land surface. Spring altitudes were calculated from 10-meter digital elevation model (DEM) data (U.S. Geological Survey, 2015; U.S. Geological Survey, 2016) . References: Kresse, T.M., and Hays, P.D., 2009, Geochemistry, Comparative Analysis, and Physical and Chemical Characteristics of the Thermal Waters East of Hot Springs National Park, Arkansas, 2006-09: U.S. Geological Survey 2009–5263, 48 p., accessed November 28, 2017, at https://pubs.usgs.gov/sir/2009/5263/. U.S. Geological Survey, 2015, USGS NED 1 arc-second n35w094 1 x 1 degree ArcGrid 2015, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html. U.S. Geological Survey, 2016, USGS NED 1 arc-second n35w093 1 x 1 degree ArcGrid 2016, accessed December 5, 2017, at The National Map: Elevation at https://nationalmap.gov/elevation.html.

These data include groundwater-level data from 59 wells measured from July to August 2017. Measured groundwater data are also available from the USGS National Water Information System (U.S. Geological Survey, 2018) Well locations were selected from three sources: previously reported sites (Kresse and Hays, 2009), site reconnaissance, and driller’s logs obtained from the Arkansas Natural Resources Commission driller database. Reference: U.S. Geological Survey, 2018, USGS water data for the Nation: U.S. Geological Survey National Water Information System database, accessed 1 July 2017 at http://dx.doi.org/10.5066/F7P55KJN.

These data include groundwater-level data from 59 wells measured from July to August 2017. Measured groundwater data are also available from the USGS National Water Information System (U.S. Geological Survey, 2018) Well locations were selected from three sources: previously reported sites (Kresse and Hays, 2009), site reconnaissance, and driller’s logs obtained from the Arkansas Natural Resources Commission driller database. Reference: U.S. Geological Survey, 2018, USGS water data for the Nation: U.S. Geological Survey National Water Information System database, accessed 1 July 2017 at http://dx.doi.org/10.5066/F7P55KJN.

This dataset contains 20-ft contours for the 2013 Sparta-Memphis aquifer potentiometric-surface map in Arkansas. The potentiometric-surface shows altitudes at which the water levels would have risen in tightly-cased wells and represents conditions during the period from January through May 2013. Groundwater-level data from 306 wells cased completely in and with the screened interval open to the Sparta-Memphis aquifer are publicly available from the U.S. Geological Survey’s National Water Information System.

This dataset contains 20-ft contours for the 2013 Sparta-Memphis aquifer potentiometric-surface map in Arkansas. The potentiometric-surface shows altitudes at which the water levels would have risen in tightly-cased wells and represents conditions during the period from January through May 2013. Groundwater-level data from 306 wells cased completely in and with the screened interval open to the Sparta-Memphis aquifer are publicly available from the U.S. Geological Survey’s National Water Information System.

This dataset contains manually developed 5-, 10-, and 500-ft contours for the Harney Basin, Oregon aquifer system shallow and deep potentiometric-surface maps. The potentiometric-surfaces show altitude at the water-table surface (shallow) and at which the water level would have risen in tightly-cased wells deeper than 100 ft (deep) and generally represents synoptic conditions during February–March of 2018. The water-table map was developed using groundwater-level measurements from shallow wells (generally less than 100 ft deep in the lowlands) and the altitudes of springs and gaining stream reaches and constrained by the altitude of the land surface. The deeper potentiometric-surface map was developed using measurements from wells generally more than 100 ft deep in the lowlands. The hydraulic-head distributions depicted are generalizations. The large study area, availability of water-level measurements, the distribution of wells across Harney Basin, and resource limitations precluded mapping all the complexities of the head distribution. Contours are most detailed and have 10-ft intervals (with the exception of the 4,095-ft contour) in the Harney Basin lowlands where data are more abundant, and the land surface is relatively flat. Groundwater heads of 4,200 ft or more were mapped using 500-ft contour intervals and generally coincide with upland areas where wells are sparse and groundwater head is strongly controlled by topography.

This dataset contains manually developed 5-, 10-, and 500-ft contours for the Harney Basin, Oregon aquifer system shallow and deep potentiometric-surface maps. The potentiometric-surfaces show altitude at the water-table surface (shallow) and at which the water level would have risen in tightly-cased wells deeper than 100 ft (deep) and generally represents synoptic conditions during February–March of 2018. The water-table map was developed using groundwater-level measurements from shallow wells (generally less than 100 ft deep in the lowlands) and the altitudes of springs and gaining stream reaches and constrained by the altitude of the land surface. The deeper potentiometric-surface map was developed using measurements from wells generally more than 100 ft deep in the lowlands. The hydraulic-head distributions depicted are generalizations. The large study area, availability of water-level measurements, the distribution of wells across Harney Basin, and resource limitations precluded mapping all the complexities of the head distribution. Contours are most detailed and have 10-ft intervals (with the exception of the 4,095-ft contour) in the Harney Basin lowlands where data are more abundant, and the land surface is relatively flat. Groundwater heads of 4,200 ft or more were mapped using 500-ft contour intervals and generally coincide with upland areas where wells are sparse and groundwater head is strongly controlled by topography.

This data set contains the potentiometric water-level altitude contours representing the 2009 potentiometric surface of the basin fill groundwater system of Dixie Valley, west-central Nevada.