Indiana Geological and Water Survey
Link to: Indiana Geological and Water Survey Groundwater Information
NGWMN Contact:
Ginger Davis (Groundwater Network)
(812) 855-1364
gindavis@iu.edu
Tracey Branham (Springs)
812-855-8390
tbranam@indiana.edu
Indiana Geological and Water Survey (IGWS) is a water-level data provider to the National Groundwater Monitoring Network (NGWMN). IGWS actively monitors 33 well sites as part of the Indiana Water Balance Network. Of these, 12 have been added to the NGWMN Portal. The focus of the IGWS groundwater monitoring program is to establish baseline conditions and track longterm water-level fluctuation trends. IGWS has been a part of the Network since 2016.
IGWS provides water-level data from the Mississippian aquifer, and Aquifers of Alluvial or Glacial origin.
NGWMN Projects:
2016 Round 2: 9/1/2016 to 8/31/2018
Initial project to become a NGWMN data provider. Well registry was completed for 12 IGWS NGWMN sites. Web services were developed and posted for water-level, lithology, well casing, and well screen data/metadata for sites where the necessary information was readily available.
Project provides an expansion of services, persistent data services, and the funding for two new monitoring wells.
2019: 12/31/2019 to 12/29/2021
Project is to drill 2 new wells to fill gaps in the NGWMN. One well will complement a current shallow well with a deep well that better represents the aquifer conditions. The second well will fill a gap in the Network in an area with groundwater availability concerns. Seismic survey work will be conducted as match to site the wells in the deepest parts of the aquifer.
2020: 9/1/2020 to 8/31/3022
Project is to provide persistent data services for two years to ensure that data continues to flow to the NGWMN Data Portal, and that sites and site information are up to date. They will redevelop and well integrity testing on 12 wells. They will also drill two new wells and one replacement well.
Project is to add springs to the NGWMN. About 20 springs will be selected for inclusion in the NGWMN and they will set up web services to serve the data for the springs to the NGWMN.
NGWMN Presentations:
March 2023 presentation from the 2023 NGWMN Data Providers meeting
Site Selection and Classification
Site Selection
The groundwater monitoring sites were selected based on four primary criteria:
- Density/spatial distribution throughout Indiana
- Depth relative to other wells in the vicinity
- Unique representation of regional (IDNR, 2011) and national aquifers (ACWI, 2013)
- Availability of minimum data requirements as outlined in the NGWMN Framework Document
Multiple wells are present at each site but the deeper well was typically selected for inclusion in the NGWMN because these wells could represent more extensive, regional aquifers.
Site Classification
The focus of the IGWS groundwater monitoring program is to establish baseline conditions and track longterm water-level fluctuation trends. Hence, each of the selected wells are categorized as "Trend" monitoring wells, consistent with the NGWMN Framework Document.
Data Collection Techniques
Groundwater-level data were compiled for the NGWMN water-level web service for the deepest monitoring wells at each monitoring location. Sites were routinely visited on average every 12 weeks to conduct maintenance and collect both manual and automated water-level data. Manual measurements of groundwater level and total well depth are made from the well reference point, typically the top of well casing marked by an indelible marker, using a Geotech ET electronic-tape meter (accuracy = +0.01 ft). The measurement, date, and time are recorded on field sheets and well sediment accumulation is noted, if present.
Two sites have vented pressure transducers connected to a datalogger, which can be downloaded either directly using a laptop computer or remotely via a modem. Monitoring wells instrumented with unvented (i.e., absolute) pressure transducers with internal memory are downloaded during routine site visits immediately following manual water-level measurement. Barometric pressure sensors located at the site are also downloaded and raw water-level data are compensated for barometric effects using sensor manufacturer software. The uncorrected water-level, barometric and compensated water-level data are stored on a field laptop hard drive and then transferred to a network directory upon field personnel's return to the office.
Locations are determined for the top of the well casing (TOC), the ground surface immediately adjacent to the well and the top of the protective well cover (if present). GPS location data are stored in the Leica controller and the following information are transferred to a well metadata spreadsheet when field personnel's return to the office:
- Point ID
- Northing
- Easting
- Elevation
- Accuracy (3D CQ)
- Notes
Data Management
In accordance with the NGWMN Framework Document, continuous water-level data are calibrated against manual water-level determinations. Compensated water-level data, reported as water-column depth, are entered into an Excel worksheet along with manual measurements that are temporally coincident to the nearest hour. The manual depth-to-water measurements are converted to groundwater elevation by subtracting depth-to-water measurements and well casing riser heights from the RTK GPS determined ground elevation (meters) at the well. Compensated water column measurements are plotted on the x-axis of an XY scatter plot and manually-determined groundwater elevations are expressed on the y-axis. A linear trendline is fit through the data to establish the linear relationship between the variables and a regression coefficient of determination (R2) greater than 0.85 is used to ensure a consistent relationship. If the pressure transducer is replaced or moved within the well column, a new regression equation is generated to update the calibration. The resulting linear transform equation is used to convert hourly compensated water-column depth readings to groundwater elevations relative to the ground surface in a separate worksheet. Data are plotted to show the groundwater hydrograph for the entire monitoring period and a visual QA/QC check is done to verify that the periodic manual measurements correspond well with the continuous record.
Other Agency Information
The Indiana Water Balance Network
Indiana Geological Survey Groundwater Information