<p>In Minnesota, mains water is delivered by local public water systems, regulated by the Minnesota Dept of Health (MDH), Drinking Water Protection under the US EPA Safe Drinking Water Act. Typical hardness: Hard; commonly above 120 mg/l, home softening widespread. For a specific ZIP, see the EWG Tap Water Database.</p>
Sources: Minnesota Dept of Health (MDH), Drinking Water Protection, EWG Tap Water Database