Compliance sample results are copied from Idaho DEQ Drinking Water Watch. System inventory and violations come from EPA SDWIS. Groundwater samples for well estimates come from the USGS Water Quality Portal and the Idaho Department of Water Resources. Hardness, sodium and total dissolved solids come from each system's Consumer Confidence Report. Data built 2026-09-15.
Tap and Well is independent. It is not affiliated with Idaho DEQ, EPA, or any water utility. We may earn a commission if you buy through these links. Rankings come from the matching engine (certification + flagged contaminants + annual cost), not from who pays more. Every number links to its source page so you can check it. Corrections are welcome.