In North Dakota, mains water is delivered by local public water systems, regulated by the North Dakota Dept of Environmental Quality (NDDEQ), Drinking Water Program under the US EPA Safe Drinking Water Act. Typical hardness: Hard; lime-soda softening common, Bismarck ~132 mg/l. For a specific ZIP, see the EWG Tap Water Database.
Sources: North Dakota Dept of Environmental Quality (NDDEQ), Drinking Water Program, EWG Tap Water Database