<p>In South Dakota, mains water is delivered by local public water systems, regulated by the South Dakota Dept of Agriculture and Natural Resources (DANR), Drinking Water Program under the US EPA Safe Drinking Water Act. Typical hardness: Moderately hard to very hard statewide. For a specific ZIP, see the EWG Tap Water Database.</p>
Sources: South Dakota Dept of Agriculture and Natural Resources (DANR), Drinking Water Program, EWG Tap Water Database