Groundwater Quality Database
The Illinois State Water Survey maintains a groundwater quality database for samples collected from wells in Illinois. Data sources include Illinois Environmental Protection Agency (IEPA) ambient water quality data, from public water supply wells dating back to the 1970s, ISWS Public Service Laboratory (PSL) data, primarily from domestic wells, ISWS research project data, and several other sources. There are more than 60,000 samples in the database dating back to the 1890s. The data are searchable by location, facility, specific well, well depth, aquifer tapped, sample date, sample number, and water quality parameter(s).
