U.S. Geological Survey 20150731 Spatial data geodatabase Reston, VA U.S. Geological Survey https://water.usgs.gov/lookup/getspatial?ds11hghpln_a10 This geodatabase includes spatial datasets that represent the High Plains aquifer in the States of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming. Included are: (1) polygon extents; datasets that represent the aquifer system extent, (2) raster datasets for the altitude of the top and bottom surfaces of the High Plains aquifer, (3) altitude contours of the top surface and of the bottom surface used to generate the surface rasters. The altitude contours are supplied for reference. The extent of the High Plains aquifer is from the digital dataset U.S. Geological Survey Data Series 543 (USGS DS 543), and as a references, the digital version of the aquifer extent presented in the Groundwater Atlas of the United States (the U.S. Geological Survey Hydrologic Atlas 730-D, -E, and -C, (USGS HA 730-D, -E, -C). The altitude contours for the top surface of the High Plains aquifer are from digital datasets of U.S. Geological Survey Open-File Report 99-263 (USGS OFR 99-263), using the 1980 water-level data. The altitude contours for the bottom surface of the High Plains aquifer are from the U.S. Geological Survey Open-File Report 98-393 (USGS OFR 98-393). The altitude of the bottom surface, or base, was originally from the High Plains Regional Aquifer-System Analysis study. The resultant top and bottom altitude values were interpolated into surface rasters within a GIS using tools that create hydrologically correct surfaces from contour data, derive the altitude from the thickness (depth from the land surface), and merge the subareas into a single surface. The primary tool was an enhanced version of "Topo to Raster" used in ArcGIS, ArcMap, Esri 2014. The raster surfaces were corrected for the areas where the altitude of an underlying layer of the aquifer exceeded the altitude of an overlying layer. These data were combined into geodatabases to be part of the Saline Groundwater Assessment Program datasets, collected under the auspices of the Office of Groundwater to be used to investigate the locations of usable inland brackish and saline groundwater across the United States. The National Water-Quality Assessment Project (NAWQA) also assisted with support, which enabled the data to be published in the USGS National Spatial Data Infrastructure (NSDI) Node archive, and therefore available for use by the public. This file geodatabase contains the following feature datasets, feature classes, images, and the surface altitude rasters: 1. ds11HGHPLN_altitude_contours: Feature dataset containing all line feature class contours for the High Plains aquifer a. ds11HGHPLN_bot_OFR98393_hpaqbase; contours of altitude of bottom of the aquifer, from USGS OFR 98-393. b. ds11HGHPLN_top_OFR99_263_wt1980; contours of altitude of top of the aquifer, from USGS OFR 99-263. 2. ds11HGHPLN_extents: Feature dataset containing polygon feature class areal extents for the High Plain aquifer a. ds11HGHPLN_erev_DS543: Areal extent of the entire High Plains aquifer; from USGS DS 543 aquifer base 3. Altitude-corrected surface raster datasets of the top and the bottom of the High Plains aquifer. The altitude values are in feet about the NAVD88 vertical datum. a. r11HGHPLN_top_a; Altitude of top of the High Plains aquifer b. r11HGHPLN_bot_a; Altitude of bottom of the High Plains aquifer 2015 Publication date Complete None planned -106.01620352 -96.228405627 43.806318258 31.598356302 USGS Thesaurus inlandWaters extent groundwater aquifer aquifer system High Plains aquifer USGS Metadata Identifier USGS:dc33395f-96ca-48f8-81be-2168d3114ebf Geographic Names Information System (GNIS) United States Colorado Kansas Nebraska New Mexico Oklahoma South Dakota Texas Wyoming None. Acknowledgement of the U.S. Geological Survey would be appreciated in products derived from these data. The original data were intended to be used at a regional scale of 1:2,500,000. Users are advised to read the dataset's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, Midwest Region Jennifer S. Stanton Hydrologist mailing address

5231 South 19th Street

Lincoln NE 68512 USA 402-261-0458 402-331-9062 jstanton@usgs.gov https://water.usgs.gov/GIS/browse/ds11HGHPLN_A10.jpg Illustration of dataset jpg Virginia L. McGuire, USGS, data compilation; Jeremy Vinton, USGS, for digitizing vector linework; Julian A. Heilman, USGS, for GIS processing and metadata creation; Roy Sando, USGS, for data and metadata review; Sharon Qi and Stephen Char, USGS, for metadata review; and the USGS NAWQA program for supporting data release. Environment as of Metadata Creation: Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 10.2 (Build 3497) Service Pack [N/A] (Build [N/A]) Extent(s): The areal extent for the High Plains aquifer is an unmodified copy of the digital polygon dataset from USGS DS 543. Contours: The vector contour data were collected in digital form from USGS OFR 99-263, and USGS OFR 98-393. The altitude values were checked against the published values of altitude. Surface Rasters: The surface rasters for the land surface and the aquifer subunits were checked against the original contours of the cited digital line datasets by creating contours from the surface raster, and comparing to the digitized originals via overlay processes. Resultant rasters were corrected for any instances where the processes created a cell where the altitude value of a top surface exceeded the altitude value of the land surface and where the altitude of a bottom surface exceeded that of the upper surface. To correct the altitude values of subsequent underlying surface raster datasets, values of underlying surface raster cells were compared to the values of the cells of the immediately overlying surface raster. When any cell of an underlying surface raster had a value greater than that of a spatially coincident cell of an immediately overlying surface raster, the cell from the underlying surface raster was given the value of the overlying surface raster at that cell. A toolset was created in ArcGIS ModelBuilder to automate this task, using the "Mosaic to New Raster" tool, and integrating the minimum value of the comparison of both the overlying and underlying surface rasters, thus ensuring that the underlying surface raster altitude values would not exceed the altitude values of the cells of the overlying surface raster. The correction steps were; (1) to change the altitude values of those cells that exceeded the altitude values of the land surface equal to the land surface (2) to make the value of the altitude of the bottom cells that exceeded the altitude values of the corrected altitudes of the top surface equal to the corrected top altitude values. Extent(s): This layer was informally inspected for completeness and logical consistency by visual comparison to the original datasets and GIS overlay processes. Contours: Digital lines were compared to the original digital linework via GIS overlay processes, and corrected if any gaps or values were missing or incorrect. Surface Rasters: Contour check lines were created from the rasters during the raster-creation processes. A cell-query check was done within a GIS to compare altitude values of the tops and bottoms of each subunit surface raster. Processes to correct the raster cells with altitude exceedance are outlined in the Attribute Accuracy section. Extent(s): Data are complete as per the explanation in the Attribute Accuracy Report. Contours: The contour data were checked against the original figures to ensure all linework was present, and that the linework was attributed correctly. Surface Rasters: Cell values have been corrected as per procedures described in the Attribute Accuracy Report. Informal inspection of digitized linework aligned with original linework. Informal inspection of altitude check contours agreed with original linework. Spot check of top altitudes and bottom altitudes to be in agreement, except for the areas of exceedance.These were set to top altitude. U.S. Geological Survey 20010801 Digital Resources Reston, VA U.S. Geological Survey http://water.usgs.gov/ogw/NatlAqCode-reflist.html Digital and/or Hardcopy Resources 1995 1997 Publication date National Aquifer Code Reference List Source provided reference for aquifer extent Qi, Sharon 2010 Vector Digital Data Set Reston, VA U.S. Geological Survey https://water.usgs.gov/GIS/metadata/usgswrd/XML/ds543.xml Digital and/or Hardcopy Resources 2010 Publication date USGS DS 543 Source provided extent of High Plains aquifer Cederstrand, J.R., and Becker, M.F. 1999 Vector Digital Data Set Reston, VA U.S. Geological Survey https://water.usgs.gov/GIS/metadata/usgswrd/XML/ofr99-263.xml Digital and/or Hardcopy Resources 1999 Publication date USGS OFR 99-263 Digital data for top of High Plains aquifer Cederstrand, J.R., Becker, M.F. 1998 Vector Digital Data Set Reston, VA U.S. Geological Survey https://water.usgs.gov/GIS/metadata/usgswrd/XML/ofr98-393_aqbase.xml Digital and/or Hardcopy Resources 1998 Publication date USGS OFR 98-393 Digital data for bottom of High Plains aquifer Robson, S.G., and Banta, E.R. 1995 Digital and/or Hardcopy Resources Reston, VA U.S. Geological Survey https://pubs.usgs.gov/ha/ha730/ Digital and/or Hardcopy Resources 1995 Publication date USGS_HA 730-C Reference for aquifer extent. Miller, J.A., and Appel, C.L. 1997 Digital and/or Hardcopy Resources Reston, VA U.S. Geological Survey https://pubs.usgs.gov/ha/ha730/ Digital and/or Hardcopy Resources 1997 Publication date USGS HA 730-D Reference for aquifer extent. Ryder, P.D. 1996 Digital and/or Hardcopy Resources Reston, VA U.S. Geological Survey https://pubs.usgs.gov/ha/ha730/ Digital and/or Hardcopy Resources 1996 Publication date USGS HA 730-E Reference for aquifer extent. Reilly, T.E., Dennehy, K.F., Alley, W.M., and Cunningham, W.L. 2008 Digital and/or Hardcopy Resources Reston, VA U.S. Geological Survey https://pubs.usgs.gov/circ/1323/ Digital and/or Hardcopy Resources 2008 Publication date USGS Circular 1323 Reference for National Aquifer Code Number attribute in extent U.S. Geological Survey 2012 Raster Digital Data Set Reston, VA U.S. Geological Survey http://nationalmap.gov/small_scale/mld/elev100.html Digital and/or Hardcopy Resources 2012 Publication date NED, 100-meter Tiff file of land surface for use as surface altitude values when determining depth of a quifer units, and as snap raster for QA/QC purposes, in a zip file named "elev48i0100a_tif.zip". Extent(s): 1. Collection of spatial datasets of the extent from the input source, a digital dataset of High Plains aquifer extent from USGS DS 543. 2. Re-projection of digitized polygon into common coordinate system and projection for analysis (USA_Contiguous_Albers_Equal_Area_Conic_USGS_version) 20130827 Surface Rasters prep: 1. Collection of digital data for creation of altitude contours. a. Digital water-level contour maps to be used as top of aquifer, USGS OFR 99-263 b. Digital aquifer base contour maps to be used as bottom of aquifer, USGS OFR 98-393 c. Collection of land surface tiff file of 100-meter resolution elevation from National Atlas (elev48i0100a_tif) 2. Re-projection of digitized lines into common coordinate system and projection for analysis (USA_Contiguous_Albers_Equal_Area_Conic_USGS_version) 3. Conversion of land-surface tiff file of 100-meter resolution elevation of the conterminous United States into raster. 4. Projected land-surface raster from WGS84 to common coordinate system and projection for analysis (USA_Contiguous_Albers_Equal_Area_Conic_USGS_version). 5. Converted the land-surface elevation values from meters to feet. 20140318 Surface Rasters creation: 1. Developed a series of tools to provide batch processing and consistency to create top and bottom rasters within the extent from the altitude contours by: a. Adding a consistent attribute name for the altitude values b. Creating a hydrologically corrected surface raster from the altitude contours. The tool created both the top and bottom surface altitude rasters using "Topo to Raster" process c. Top surface altitude rasters were developed from the values of the 1980 water-level contours, the bottom surface altitude raster from the aquifer base contours 2. Vertical datum was converted to vertical datum (NAVD 1988) if necessary. 20140318 Surface Rasters quality assurance and quality control checks: 1. Check contours were created from each layer to be compared to the original contours used to create the surface raster. 2. To find areas of exceedance, the altitude of bottom of aquifer layer was subtracted from the altitude of top of aquifer layer. 3. The altitude of the top surface was compared to the altitude of the land surface; any cells that exceeded the land surface altitude were changed to equal the land surface altitude. 4. The altitude of the bottom surface was compared to the altitude of the corrected top surface; any cells that exceeded the altitude of the top surface were changed to equal the top surface altitude. 20140318 Creation of metadata for geodatabase: 1. Used the aquifer extent polygon for boundary coordinates 2. Used metaform pdf file values obtained from the originators as input to Metadata Wizard 3. Added NSDI Node requirements via Notepad ++ 20150717 Vector G-polygon 1 USA Contiguous Albers Equal Area Conic USGS version (ESRI Full Name: USA_Contiguous_Albers_Equal_Area_Conic_USGS_version) 29.5 45.5 -96.0 23.0 0.0 0.0 coordinate pair 0.6096 0.6096 Meter D_North_American_1983 GRS_1980 6378137.0 298.257222101 ds11HGHPLN_altitude_contours Line Feature Dataset Originator defined ds11HGHPLN_bot_OFR98393_hpaqbase Line Feature Class Originator defined OBJECTID Identifying numeric used by software Producer defined 1 357 None Shape Used by software Producer defined Polyline Feature geometry Esri Shape_Length Length of line segments, in meters Esri 1349.785465 1211021.743285 meters BaseOfAquiferElevation_inFt Altitude of bottom of aquifer USGS OFR 98-393 1200 7000 feet ds11HGHPLN_top_OFR99_263_wt1980 Line Feature Class Originator defined OBJECTID Identifying numeric used by software Producer defined 1 563 None Shape Used by software Producer defined Polyline Feature geometry Esri Shape_Length Length of line segments, in meters Esri 149.508831 527830.416111 meters WaterTable1980_Elevation_inFt Altitude of bottom of aquifer USGS OFR 98-393 1100 7000 feet above NAVD 1988 ds11HGHPLN_extents Polygon Feature Dataset Originator defined ds11HGHPLN_erev_DS543 Polygon Feature Class Originator defined OBJECTID Identifying numeric used by software Esri 1 number of polygons USGS Shape Type of feature class in a GIS Esri Polygon ZM Feature geometry Esri ROCK_NAME General lithology of the rocks that make up the aquifer USGS Unconsolidated sand and gravel aquifers General lithology of this aquifer is unconsolidated sand and gravel USGS HA-730 (see Lineage) ROCK_TYPE Code for rock name USGS 100 Numeric code for "unconsolidated sand and gravel aquifers" USGS HA-730 (see Lineage) AQ_NAME Name of aquifer USGS High Plains aquifer National Aquifer Code Name of Aquifer USGS HA-730 (see Lineage) AQ_NO Principal Aquifers Code number of aquifer USGS 11 Numeric code for "High Plains Aquifer" USGS Circular 1323, Figure 2 (see Lineage) AQ_ID Principal Aquifers Code number of aquifer and aquifer name abbreviation USGS 11HGHPLN combination of AQ_NO and AQ_NAME abbreviation USGS HA-730, USGS Circular 1323, Figure 2 (see Lineage) USGS_National_Aquifer_Code USGS National Aquifer Code name for specific aquifers USGS N100HGHPLN Aquifer (N) - Rock Type (100) - Aquifer Name (HGHPLN) National Aquifer Code Reference List (see Lineage) NumSubUnits Number of subunits within aquifer system USGS 1 This aquifer has a single unit USGS HA-730 (see Lineage) SubUnitNames Subunit names of this aquifer system USGS Not Applicable There are no subunit names for this aquifer None NumSubAreas Number of subareas within aquifer system. Subareas are parts of the aquifer with different sources for aquifer top and bottom. USGS 1 This aquifer has a single area Originator defined SubAreaNames Unknown Producer defined Not Applicable There are no subarea names for this aquifer None Shape_Length Length of line segments of extent polygon (perimeter) Producer defined 24098388.0608002 Length of line segments of extent polygon in meters Producer defined Shape_Area Area of extent polygon Producer defined 452609863201.988 Area of extent Producer defined r11HGHPLN_bot_a Raster of bottom surface of surficial aquifer systems USGS Value Altitude, in feet above NAVD88 Originator defined 1124.586 7011.3291 feet above NAVD 1988 r11HGHPLN_top_a Raster of top surface of High Plains aquifer USGS Value Altitude, in feet above NAVD88 Originator defined 1095.155 7021.329 feet above NAVD 1988 This geodatabase includes spatial datasets that represent the High Plains aquifer in the States of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, Wyoming. Included are: (1) polygon extents; datasets that represent the aquifer extent, (2) raster datasets for the altitude of the top and bottom surfaces of the aquifer, (3) altitude contours used to generate the surface rasters, The digitized contours are supplied for reference. The extent of the High Plains aquifer is from the dataset from U.S. Geological Survey Data Series 543. The contour dataset of the altitude of the top of the High Plains aquifer is from U.S. Geological Survey Open-File Report 99-263. The water levels of 1980 were used as top of aquifer. The contour dataset of the altitude of the bottom of the High Plains aquifer is from U.S. Geological Survey Open File Report 98-393. The High Plains aquifer has no subunits or subareas as described in this document. U.S. Geological Survey Michael Ierardi IT Specialist mailing and physical

445 National Center

Reston Virginia 20192 USA 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov Downloadable Data Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data, software, or related materials. The use of firm, trade, or brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. The names mentioned in this document may be trademarks or registered trademarks of their respective trademark owners. Zipped Geodatabase 334 https://water.usgs.gov/GIS/dsdl/ds11HGHPLN_A10_gdb.zip Zip file of datasets in non-proprietary formats: shapefiles of vectors and points, ASCII files of surface rasters, TIF files of georeferenced images 250 https://water.usgs.gov/GIS/dsdl/ds11HGHPLN_non_prop.zip None. No fees are applicable for obtaining the dataset. 20201117 U.S. Geological Survey Michael Ierardi IT Specialist mailing and physical address

445 National Center

Reston VA 20192 USA 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov FGDC Content Standard for Digital Geospatial Metadata FGDC-STD-001-1998