The U.S. Geological Survey (USGS), in cooperation with the Pennsylvania Department of Environmental Protection (PADEP), conducted an evaluation of data used by the PADEP to identify groundwater sources under the direct influence of surface water (GUDI) in Pennsylvania (Gross and others, 2022). The data used in this evaluation and the processes used to compile them from multiple sources are described and provided herein. Data were compiled primarily but not exclusively from PADEP resources, including (1) source-information for public water-supply systems and Microscopic Particulate Analysis (MPA) results for public water-supply system groundwater sources from the agency’s Pennsylvania Drinking Water Information System (PADWIS) database (Pennsylvania Department of Environmental Protection, 2016), and (2) results associated with MPA testing from the PADEP Bureau of Laboratories (BOL) files and water-quality analyses obtained from the PADEP BOL, Sample Information System (Pennsylvania Department of Environmental Protection, written commun., various dates). Information compiled from sources other than the PADEP includes anthropogenic (land cover and PADEP region) and naturogenic (geologic and physiographic, hydrologic, soil characterization, and topographic) spatial data. Quality control (QC) procedures were applied to the PADWIS database to verify spatial coordinates, verify collection type information, exclude sources not designated as wells, and verify or remove values that were either obvious errors or populated as zero rather than as “no data.” The QC process reduced the original PADWIS dataset to 12,147 public water-supply system wells (hereafter referred to as the PADWIS database). An initial subset of the PADWIS database, termed the PADWIS database subset, was created to include 4,018 public water-supply system community wells that have undergone the Surface Water Identification Protocol (SWIP), a protocol used by the PADEP to classify sources as GUDI or non-GUDI (Gross and others, 2022). A second subset of the PADWIS database, termed the MPA database subset, represents MPA results for 631 community and noncommunity wells and includes water-quality data (alkalinity, chloride, Escherichia coli, fecal coliform, nitrate, pH, sodium, specific conductance, sulfate, total coliform, total dissolved solids, total residue, and turbidity) associated with groundwater-quality samples typically collected concurrently with the MPA sample. The PADWIS database and two subsets (PADWIS database subset and MPA database subset) are compiled in a single data table (DR_2022_Table.xlsx), with the two subsets differentiated using attributes that are defined in the associated metadata table (DR_2022_Metadata_Table_Variables.xlsx). This metadata file (DR_2022_Metadata.xml) describes data resources, data compilation, and QC procedures in greater detail.

This dataset contains all publicly-available analytical data collected by the U.S. Geological Survey (USGS) at each location within the Pennsylvania Groundwater Monitoring Network (GWMN) from 2015 to present. Additional analytical data will be appended following the conclusion of each sampling season, and all data is made publicly available in the online National Water Inventory System (NWIS). This dataset serves as a repository for data used by the Pennsylvania Groundwater Monitoring Network map, found here: https://rconnect.chs.usgs.gov/PA_GWMN_map/

This dataset contains all publicly-available analytical data collected by the U.S. Geological Survey (USGS) at each location within the Pennsylvania Groundwater Monitoring Network (GWMN) from 2015 to present. Additional analytical data will be appended following the conclusion of each sampling season, and all data is made publicly available in the online National Water Inventory System (NWIS). This dataset serves as a repository for data used by the Pennsylvania Groundwater Monitoring Network map, found here: https://rconnect.chs.usgs.gov/PA_GWMN_map/

Data from more than 75,000 community public supply wells were acquired from national and state agencies. Using the information provided by the agencies, along with surficial and bedrock geologic maps, the wells were assigned to a national Principal Aquifer (PA) as defined in USGS (2003) or a Secondary Hydrogeologic Region (SHR) as defined in Belitz et al. (2018). Collectively, both PAs and SHRs are referred to as Hydrogeologic Regions (HRs). The HR identifies the primary source of water for the well. The locations of the wells were generalized so that they plot in the center of a 2 kilometer square grid. The county information provided identifies the county the well is located within based on it’s actual location, not the generalized location. A total of 76,354 wells were assigned to an HR, 41 wells were assigned to "basement" or "bedrock" because there was not enough information to assign to a specific HR.

Data from more than 75,000 community public supply wells were acquired from national and state agencies. Using the information provided by the agencies, along with surficial and bedrock geologic maps, the wells were assigned to a national Principal Aquifer (PA) as defined in USGS (2003) or a Secondary Hydrogeologic Region (SHR) as defined in Belitz et al. (2018). Collectively, both PAs and SHRs are referred to as Hydrogeologic Regions (HRs). The HR identifies the primary source of water for the well. The locations of the wells were generalized so that they plot in the center of a 2 kilometer square grid. The county information provided identifies the county the well is located within based on it’s actual location, not the generalized location. A total of 76,354 wells were assigned to an HR, 41 wells were assigned to "basement" or "bedrock" because there was not enough information to assign to a specific HR.

The U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Conservation and Natural Resources (PA DCNR), Bureau of Geological Survey, provides time series trends results using the Mann Kendall family of analyses on select sites across Pennsylvania for baseflow, runoff, groundwater levels, and streamflow percentiles.

The U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Conservation and Natural Resources (PA DCNR), Bureau of Geological Survey, provides time series trends results using the Mann Kendall family of analyses on select sites across Pennsylvania for baseflow, runoff, groundwater levels, and streamflow percentiles.

The U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Conservation and Natural Resources (PA DCNR), Bureau of Geological Survey, provides estimates of groundwater recharge at 197 streamflow gaging stations where streamflow is relatively unaffected by regulation. Baseflow, runoff, and groundwater Recharge estimates were conducted via the Hydrologic toolbox by use of automated streamflow-hydrograph-analysis methods HySEP-Fixed, HySEP-LocMin, HySEP-Slide, PART, BFI-Standard, BFI-Modified, DF-One Param, DF-Two Param, and RORA.

The U.S. Geological Survey (USGS) in cooperation with the Pennsylvania Department of Conservation and Natural Resources (PA DCNR), Bureau of Geological Survey, provides estimates of groundwater recharge at 197 streamflow gaging stations where streamflow is relatively unaffected by regulation. Baseflow, runoff, and groundwater Recharge estimates were conducted via the Hydrologic toolbox by use of automated streamflow-hydrograph-analysis methods HySEP-Fixed, HySEP-LocMin, HySEP-Slide, PART, BFI-Standard, BFI-Modified, DF-One Param, DF-Two Param, and RORA.

Groundwater quality data for 472 domestic well-water samples were retrieved from the USGS National Water Information System (NWIS) database and combined with descriptive information on the sampled well locations. The NWIS data for a sample, collected on the selected date, were averaged into a single record (one per well), and rounded according to USGS protocols. For evaluation and reporting, the water-quality data were further combined with physical attributes and classified by lithology, topographic position, physiographic province, region, redox, and pH (as standalone matrix, one row per well). A second data matrix file incorporating minimum reporting levels for censored and low-reported values (set to 0.99X highest common reporting level) was generated for statistical analysis. The two water-quality matrix files, in comma delimited format (.csv) plus a third file that has complete descriptive information for all the water-quality and physical parameters constitute the primary products of the data release.