This dataset contains digitized groundwater quality data from 435 wells that are screened in the Chicot aquifer system. Reported values of interest included specific conductance, total dissolved solids, and chloride (Cl) concentration; other parameters and major/trace element concentrations were included if reported. Values listed as “NA” or “-9999” represent data that was not reported in the physical dataset. A concentration of 0 ppm or ppb represents a reported concentration of 0 and not a null value. Data were collected from scanned versions of well registration records obtained from the Louisiana Department of Natural Resources. Most well registration records may be accessed through Strategic Online Natural Resources Information System (SONRIS database found at https://www.sonris.com), however some records may only be available in hard copy format.