<p>In Pennsylvania, mains water is delivered by local public water systems, regulated by the Pennsylvania Dept of Environmental Protection (PA DEP), Bureau of Safe Drinking Water under the US EPA Safe Drinking Water Act. Typical hardness: Moderately hard to hard; hardest over limestone in central and eastern PA. For a specific ZIP, see the EWG Tap Water Database.</p>
Sources: Pennsylvania Dept of Environmental Protection (PA DEP), Bureau of Safe Drinking Water, EWG Tap Water Database