Newark Water Hardness & Quality Report (2026)

Newark, Ohio, the Licking County seat — a major central Ohio city known as the site of the Newark Earthworks (the largest prehistoric geometric earthworks in the world, built by the Hopewell culture circa 100 BCE–500 CE), home of the Ohio State University Newark campus, and a historic manufacturing city in the central Ohio flint and glassmaking corridor — draws its municipal water supply from the Licking River and Buckeye Lake watershed via the City of Newark Water Division. Water hardness in Newark measures 218 mg/L — classified as very hard.

Newark's very hard supply reflects the Licking River Valley's calcareous central Ohio Paleozoic geology. The Licking River above Newark drains: the Central Ohio Silurian–Devonian calcareous platform (Silurian Niagara Dolomite — highly calcareous dolomite of the Columbus area, the principal calcareous formation in central Ohio); the Devonian Columbus Limestone and Delaware Limestone (calcareous marine carbonate — very soluble calcareous limestone of the central Ohio Devonian sequence); and the Buckeye Lake State Park watershed (the Glacial Lake Newark area — calcareous lacustrine deposits). The Devonian Columbus Limestone and Silurian Niagara Dolomite karst dissolution produce the very hard 218 mg/L at Newark.

At 218 mg/L, Newark residents face significant hard water challenges. Scale deposits form rapidly on all fixtures and tile — monthly descaling with citric acid solution is essential maintenance. City of Newark Water Division consistently delivers water meeting all Ohio EPA and federal EPA Safe Drinking Water Act requirements.