This dataset includes a Microsoft Excel file, and a *.csv and a *.txt version of the Excel file, that contain location and groundwater-level data for wells open to the Valley and Ridge carbonate aquifer of Cambrian-Ordovician age in the area of Savannah and Gunstocker Creeks in northeastern Hamilton, southern Meigs, and northwestern Bradley Counties, Tennessee, for fall 1992, spring and fall 1993, summer 2008, and spring 2009 conditions. Potentiometric-surface contour data for the five measurement periods also are included as separate Earth Sciences Research Institute (ESRI) ArcGIS shapefiles. The data were collected as parts of studies conducted by the U.S. Geological Survey (USGS) in cooperation with the Chattanooga/Hamilton County Regional Planning Commission, the City of Chattanooga, Hamilton County, the Hamilton County Association of Utility Districts, and the Savannah Valley Utility District (SVUD). The well and water-level data also are available from the USGS National Water Information System (NWIS).

This dataset contains groundwater-altitude (GWA) data from wells that were used or considered (indicated by the field USE_2020) to create a potentiometric-surface map for the Mississippi River Valley alluvial aquifer (MRVA) for spring 2020. The GWA data was referenced to the North American Vertical Datum of 1988 (NAVD 88). Most of the wells were measured annually, but some wells were measured more than one time in a year and a small number of wells were measured continuously. GWA data were from wells measured in spring 2020. To best reflect hydrologic conditions in the MRVA, the GWA data used to create the 2020 potentiometric surface would be measured in a short-time frame of days or a week and there would be available data (for example from sets of wells with short-screen (about 5 to 10 feet or 1.5 to 3 meters) installed near the top, in the middle, and near the bottom of the aquifer) to indicate vertical flow components. However, most wells screened in the MRVA were measured before the potentiometric-surface map of the MRVA was planned and therefore the timing of each well's measurement(s) was determined by the needs and schedules of the entities doing the measurements. Also, many of the measured wells had longer screens (from greater than 10 feet or 3 meters and covering a substantial part of the aquifer thickness), therefore their water-level measurements represent an average head in the aquifer for that location. The resultant potentiometric-surface contours and raster represents the generalized central tendency for spring 2020, but it would not be useful for some purposes, such as for calibration of a groundwater-flow model for early April 2020 or for some local scale assessments.

A potentiometric surface map for spring 2016 was created for the Mississippi River Valley alluvial (MRVA) aquifer, which was referenced to the North American Vertical Datum of 1988 (NAVD 88), using most of the available groundwater-altitude data from wells and surface-water-altitude data from streamgages. Most of the wells were measured annually or one time, after installation, but some wells were measured more than one time in a year and a small number of wells were measured continually. Streamgages were typically operated continuously. The potentiometric surface map for 2016 was created as part of the U.S. Geological Survey (USGS) Water Availability and Use Science Program to support investigations that characterize the MRVA aquifer. The potentiometric contours ranged from 10 feet to 340 feet above NAVD 88. The regional direction of groundwater flow was generally towards the south-southwest, except in areas of groundwater-altitude depressions, where groundwater flows into the depressions, and near rivers, where groundwater flow generally parallels the flow in the rivers. There are large depressions in the potentiometric surface in the lower half of the Cache region and in most of the Grand Prairie and Delta regions.

This dataset contains groundwater-altitude (GWA) data from wells that were used or considered (indicated by the field USE_2020) to create a potentiometric-surface map for the Mississippi River Valley alluvial aquifer (MRVA) for spring 2020. The GWA data was referenced to the North American Vertical Datum of 1988 (NAVD 88). Most of the wells were measured annually, but some wells were measured more than one time in a year and a small number of wells were measured continuously. GWA data were from wells measured in spring 2020. To best reflect hydrologic conditions in the MRVA, the GWA data used to create the 2020 potentiometric surface would be measured in a short-time frame of days or a week and there would be available data (for example from sets of wells with short-screen (about 5 to 10 feet or 1.5 to 3 meters) installed near the top, in the middle, and near the bottom of the aquifer) to indicate vertical flow components. However, most wells screened in the MRVA were measured before the potentiometric-surface map of the MRVA was planned and therefore the timing of each well's measurement(s) was determined by the needs and schedules of the entities doing the measurements. Also, many of the measured wells had longer screens (from greater than 10 feet or 3 meters and covering a substantial part of the aquifer thickness), therefore their water-level measurements represent an average head in the aquifer for that location. The resultant potentiometric-surface contours and raster represents the generalized central tendency for spring 2020, but it would not be useful for some purposes, such as for calibration of a groundwater-flow model for early April 2020 or for some local scale assessments.

This polyline shapefile consists of digital contours that represent the potentiometric-surface altitude of water in the Lloyd and contiguous North Shore aquifer beneath Long Island, New York. The U.S. Geological Survey constructed a potentiometric-surface altitude map using ground-water levels measured in the Lloyd and North Shore aquifers during the spring of 2013. Contours were constructed at a scale of 1:125,000 from water-level data collected at 66 groundwater monitoring wells. The potentiometric-surface altitude contours were digitized and compared to 1997, 2006, and 2010 potentiometric-surface altitude maps. The contours range from -10 to 60 feet at 5 foot intervals above and below the National Geodetic Vertical Datum of 1929. This polyline shapefile is a digital representation of the potentiometric-surface contours presented in sheet 3 of Scientific Investigations Map 3326.

This dataset contains groundwater (GW)-altitude (ALT) data from wells that was used or considered to create a potentiometric-surface map for the Mississippi River Valley alluvial (MRVA) aquifer for spring 2018. The groundwater-altitude data was referenced to the North American Vertical Datum of 1988 (NAVD 88). Most of the wells were measured annually, but some wells were measured more than one time in a year and a small number of wells were measured continuously. Groundwater-altitude data were from wells measured in spring 2018. Spring-time measurements were preferred because water levels had generally recovered from pumping during the previous irrigation season and it was before pumping began for the current irrigation season. To best reflect hydrologic conditions in the MRVA aquifer, the groundwater altitudes used to create the 2018 potentiometric surface would be measured in a short-time frame of days or a week and there would be available data (for example from sets of wells with short-screen (about 5 to 10 feet or 1.5 to 3 meters) installed near the top, in the middle, and near the bottom of the aquifer) to indicate vertical flow components. However, most wells screened in the MRVA aquifer were measured before the potentiometric-surface map of the MRVA aquifer was planned and therefore the timing of each well’s measurement(s) was determined by the needs and schedules of the entities doing the measurements. Also, many of the measured wells had longer screens (from greater than 10 feet or 3 meters and covering a substantial part of the aquifer thickness), therefore their water-level measurements represent an average head in the aquifer for that location. The resultant potentiometric-surface contours and raster represents the generalized central tendency for spring 2018, but it would not be useful for some purposes, such as for calibration of a groundwater-flow model for early April 2018 or for some local scale assessments.

This dataset contains groundwater (GW)-altitude (ALT) data from wells that was used or considered to create a potentiometric-surface map for the Mississippi River Valley alluvial (MRVA) aquifer for spring 2018. The groundwater-altitude data was referenced to the North American Vertical Datum of 1988 (NAVD 88). Most of the wells were measured annually, but some wells were measured more than one time in a year and a small number of wells were measured continuously. Groundwater-altitude data were from wells measured in spring 2018. Spring-time measurements were preferred because water levels had generally recovered from pumping during the previous irrigation season and it was before pumping began for the current irrigation season. To best reflect hydrologic conditions in the MRVA aquifer, the groundwater altitudes used to create the 2018 potentiometric surface would be measured in a short-time frame of days or a week and there would be available data (for example from sets of wells with short-screen (about 5 to 10 feet or 1.5 to 3 meters) installed near the top, in the middle, and near the bottom of the aquifer) to indicate vertical flow components. However, most wells screened in the MRVA aquifer were measured before the potentiometric-surface map of the MRVA aquifer was planned and therefore the timing of each well’s measurement(s) was determined by the needs and schedules of the entities doing the measurements. Also, many of the measured wells had longer screens (from greater than 10 feet or 3 meters and covering a substantial part of the aquifer thickness), therefore their water-level measurements represent an average head in the aquifer for that location. The resultant potentiometric-surface contours and raster represents the generalized central tendency for spring 2018, but it would not be useful for some purposes, such as for calibration of a groundwater-flow model for early April 2018 or for some local scale assessments.

This dataset contains groundwater (GW)-altitude (ALT) data from wells that was used or considered to create a potentiometric-surface map for the Mississippi River Valley alluvial (MRVA) aquifer for spring 2018. The groundwater-altitude data was referenced to the North American Vertical Datum of 1988 (NAVD 88). Most of the wells were measured annually, but some wells were measured more than one time in a year and a small number of wells were measured continuously. Groundwater-altitude data were from wells measured in spring 2018. Spring-time measurements were preferred because water levels had generally recovered from pumping during the previous irrigation season and it was before pumping began for the current irrigation season. To best reflect hydrologic conditions in the MRVA aquifer, the groundwater altitudes used to create the 2018 potentiometric surface would be measured in a short-time frame of days or a week and there would be available data (for example from sets of wells with short-screen (about 5 to 10 feet or 1.5 to 3 meters) installed near the top, in the middle, and near the bottom of the aquifer) to indicate vertical flow components. However, most wells screened in the MRVA aquifer were measured before the potentiometric-surface map of the MRVA aquifer was planned and therefore the timing of each well’s measurement(s) was determined by the needs and schedules of the entities doing the measurements. Also, many of the measured wells had longer screens (from greater than 10 feet or 3 meters and covering a substantial part of the aquifer thickness), therefore their water-level measurements represent an average head in the aquifer for that location. The resultant potentiometric-surface contours and raster represents the generalized central tendency for spring 2018, but it would not be useful for some purposes, such as for calibration of a groundwater-flow model for early April 2018 or for some local scale assessments.

This map shows the USGS (United States Geologic Survey), NWIS (National Water Inventory System) Hydrologic Data Sites for Piute County, Utah. The scope and purpose of NWIS is defined on the web site: http://water.usgs.gov/public/pubs/FS/FS-027-98/

This map shows the USGS (United States Geologic Survey), NWIS (National Water Inventory System) Hydrologic Data Sites for Piute County, Utah. The scope and purpose of NWIS is defined on the web site: http://water.usgs.gov/public/pubs/FS/FS-027-98/