Portsmouth Water Hardness & Quality Report (2026)

Portsmouth, Ohio, in Scioto County — the Scioto County seat on the Ohio River at the mouth of the Scioto River, a historic Ohio River port city, home of the Portsmouth Floodwall Murals (the world's largest outdoor mural project), and in Scioto County — heavily impacted by the opioid crisis that defines much of the public health narrative of the Appalachian Ohio River valley communities — receives its municipal water from Portsmouth Water Works, which draws from the Scioto River at the Portsmouth intake.

The hard 208.5 mg/L hardness and elevated TDS of 482.5 mg/L reflect the Scioto River watershed's central to southern Ohio geology. The Scioto River drains central and southern Ohio — the Western Ohio Till Plain (Silurian-Devonian carbonate platform, Pleistocene glacial till) upstream and the Appalachian Plateau transition zone (Pennsylvanian marine limestone, calcareous shale, and sandstone) downstream in the Scioto Brush Creek watershed. The moderately hard dolomite and limestone of the Ohio carbonate platform (same geological sequence as the Great Miami Valley — Silurian Niagara Dolomite, Devonian limestone) contributes the consistent Ohio hard water character.

At 208.5 mg/L, Portsmouth's water is hard — scale builds in kettles and appliances within weeks, dishwashers require rinse aid, and bathroom fixtures develop calcium deposits. Monthly descaling is practical. A water softener is recommended. The PFAS level of 8.2 ppt warrants a certified drinking water filter — the Portsmouth Gaseous Diffusion Plant (now the Southern Ohio Diversification Initiative — a former uranium enrichment facility adjacent to Portsmouth) is a significant industrial chemical source in the Scioto Valley, alongside the Ohio River industrial corridor's broader PFAS legacy.