Granite City Water Hardness & Quality Report (2026)

Granite City, Illinois, in Madison County — a major south Illinois Metro East steel and manufacturing city (Granite City is a significant Madison County city — one of the most important steel and industrial cities in the St. Louis Metro East (Illinois); Granite City was home of the massive United States Steel (USS) and later EVRAZ North America steel mill (one of the last operating integrated steel mills in the St. Louis metro area — the Granite City Works steel mill has been a major employer in Madison County since the early 20th century; the mill has been idled and restarted multiple times, representing the broader story of Midwest steel industry decline and selective revival)), a diverse Madison County community with a significant Eastern European-American (Czech-American, Slovak-American, Polish-American), African-American, and working-class population (Granite City's ethnic diversity reflects its early 20th century immigrant labor history), adjacent to Madison and Venice in the south Metro East industrial corridor, and a community defined by its steel and industrial heritage — draws its municipal water supply from the Mississippi River via the Granite City Public Water Supply Division. Water hardness in Granite City measures 164.5 mg/L — classified as hard.

Granite City's hard supply reflects the south Illinois Madison County Mississippi River supply's calcareous character. The Mississippi River at Granite City–Madison County carries dissolved carbonates from upstream Ozark Plateau and Illinois Basin limestone geology. Granite City applies limited softening, producing the hard 164.5 mg/L.

At 164.5 mg/L, Granite City residents face regular hard water challenges. Monthly descaling and water softeners are recommended. Granite City Public Water Supply Division consistently delivers water meeting all Illinois EPA and EPA Safe Drinking Water Act requirements.