Zionsville Water Hardness & Quality Report (2026)

Zionsville, Indiana, in Boone County — a major north Indianapolis affluent suburban community (Zionsville is a significant Boone County town — one of the most affluent and distinctive suburban communities in the Indianapolis metropolitan area; Zionsville is known for its charming brick-paved Main Street and its extraordinary preservation of small-town character within the Indianapolis metro (Zionsville's historic brick Main Street — one of the most distinctive and well-preserved historic downtown streets in Indiana — is a major destination for dining, boutique retail, and community events; Zionsville's commitment to preserving its historic character while growing as an upscale suburb is one of the most successful examples of suburban historic preservation in the Midwest)); Zionsville is one of the most sought-after communities in the Indianapolis metropolitan area for upper-income families (Zionsville's schools — particularly Zionsville Community High School — are consistently among the highest performing in Indiana; the community attracts significant corporate executive and professional families), a diverse Boone County community with a primarily professional, affluent, and suburban family population — draws its municipal water supply via the Indiana American Water. Water hardness in Zionsville measures 128.5 mg/L — classified as moderately hard.

Zionsville's moderate hardness reflects the north Indianapolis Boone County glaciated carbonate corridor's calcareous character. The Eagle Creek watershed draws from the Ordovician Indiana limestone and glacial till with effective treatment, producing the moderately hard 128.5 mg/L.

At 128.5 mg/L, Zionsville residents encounter moderate scale accumulation. Monthly cleaning is recommended. Indiana American Water consistently delivers water meeting all Indiana DEM and EPA Safe Drinking Water Act requirements.