Trotwood Water Hardness & Quality Report (2026)

Trotwood, Ohio, in Montgomery County northwest of Dayton, receives its municipal water from the City of Dayton Water Division or Greater Dayton Water Authority, drawing from the Great Miami Buried Valley Aquifer — one of the most studied and celebrated groundwater resources in the United States. The Great Miami Buried Valley is a 120-mile ancient river valley scoured by glaciers and then filled with clean, thick glacial outwash gravel and sand, creating a prolific natural filter system that delivers high-quality water to Dayton metro communities including Trotwood.

The hard 183.5 mg/L hardness and TDS of 390.4 mg/L reflect the Great Miami Buried Valley's carbonate-rich character. The thick Pleistocene glacial outwash filling the buried valley was derived primarily from Silurian and Devonian limestone and dolomite formations of the Ohio carbonate plain — the same formations (including the Silurian Bass Islands Dolomite, Salina Group evaporites, and Devonian Columbus and Delaware Limestones) producing hard water throughout western and central Ohio. As groundwater percolates through these calcareous outwash materials, it picks up substantial calcium and magnesium bicarbonate, producing consistently hard water throughout the Miami Valley supply zone.

At 183.5 mg/L, Trotwood residents deal with hard water affecting household systems consistently. Scale accumulates in kettles and coffee machines within weeks, dishwashers benefit from rinse aid to prevent mineral film on glassware, and bathroom fixtures require periodic acidic cleaning to manage calcium deposits. Descaling appliances every six to eight weeks is the practical cadence for Dayton metro households. The PFAS level of 7.2 ppt warrants use of a certified drinking water filter — the Dayton area's dense manufacturing heritage and proximity to Wright-Patterson Air Force Base contribute to elevated PFAS in the regional water supply.