GEOSPATIAL ANALYSIS INVESTIGATING SPRINGS, SHALLOW WELLS AND DRILLED WELLS AS SOURCE OF BACTERIA IN PRIVATE DRINKING WATER

Phone call records from 2017 show that the majority of well owners calling Department of Health have questions regarding bacterial contamination of well water. To understand the extend of bacterial well water contamination and potential relationships to water source, we investigated the existing water quality data from the Vermont Department of Health Lab, and the relationship to drilled wells versus shallow wells and springs. Lab data based on total coliform and E. coli presence in drinking water was geocoded in ArcGIS and combined with geospatial layers of the extend of public water systems and location of drilled wells from the state well log reported by licensed well drillers since 1966. The maps will be used to increase awareness about bacterial contamination throughout the State of Vermont and potential relationship to water source. Besides informing sanitarians, well drillers and other water quality professionals about the vulnerability of shallow wells and springs versus drilled wells, the maps can help identify target areas for public health outreach.