Data & Sources — Mackinac County

How we built the Mackinac County well water report: sample counts, data sources, and confidence tiers.

Sample Summary

37418 total samples analyzed for Mackinac County. Data spans 1976 to 2015.

Confidence Tiers

Data Sources

This report aggregates data from the following public databases:

Methodology

Raw records are normalized to µg/L, deduplicated by sample ID, and filtered to remove certified outliers. Analyte names are mapped to EPA canonical forms. See the full methodology page for details.

Last updated: 2026-05-08