Data associated with potentiometric surface, Mississippi River Valley alluvial aquifer, spring 2016
Dates
Publication Date
2019-09-11
Begin Position
2016-01-01
End Position
2016-05-31
Citation
McGuire, V.L., Seanor, R.C., Asquith, W.H., Kress, W.H., Strauch, K.R., and Flynn, A.T., 2019, Data associated with potentiometric surface, Mississippi River Valley alluvial aquifer, spring 2016: U.S. Geological Survey data release, https://doi.org/10.5066/P9SV1HMQ.
Summary
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. [...]
Summary
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.
Click on title to download individual files attached to this item.
Related External Resources
Type: Related Primary Publication
McGuire, V.L., Seanor, R.C., Asquith, W.H., Kress, W.H., and Strauch, K.R., 2019, Potentiometric surface of the Mississippi River Valley alluvial aquifer, spring 2016: U.S. Geological Survey Scientific Investigations Map 3439, 14 p., 5 sheets, https://doi.org/10.3133/sim3439.
The purpose of this study was to prepare and present a potentiometric-surface-contour map for the current extent of the MRVA aquifer using (1) groundwater-altitude data from wells measured in spring 2016, which is after water levels have generally recovered from pumping in the previous irrigation season and before pumping begins for the current irrigation season, and (2) the altitude in spring 2016 of the top of the water surface in rivers and streams, hereinafter referred to as surface-water altitude, from streamgages in the area. To best reflect hydrologic conditions in the MRVA aquifer, the groundwater altitudes used to create the 2016 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 short-screened wells 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 have long screens, therefore their water-level measurements represent an average head in the aquifer for that location. For this study, recognizing the limitations of the available data, it was decided to assess all available groundwater-altitude data from wells measured from January to May 2016 for use in the potentiometric surface map for spring 2016. The resultant potentiometric surface would then represent the generalized central tendency for spring 2016, but it would not be useful for some purposes, such as for calibration of a groundwater flow model for early April 2016 or for some local scale assessments.
