This data set contains raw data from 12 international groundwater studies that monitored for human viruses and microbial indicators. Please see the first worksheet for identification of the studies used. This dataset is associated with the following publication: Fout, S., M. Karim, and M. Borchardt. Human virus and microbial indicator occurrence in public-supply groundwater systems: meta-analysis of international studies. Hydrogeology Journal. Springer, Heidelburg, GERMANY, 25(0): 903-919, (2017).