East Saint Louis Water Hardness & Quality Report (2026)

East Saint Louis, Illinois, in Saint Clair County — a major southwest Illinois Mississippi River city (East Saint Louis is a significant Saint Clair County city — one of the most historically important and economically challenged cities in the Midwest; East Saint Louis is directly across the Mississippi River from St. Louis, Missouri, connected by the Poplar Street Bridge and other crossings; East Saint Louis was one of the most prosperous industrial and commercial cities in the Midwest in the early 20th century, with major railroad yards, meatpacking plants, and aluminum smelters; the 1917 race riot (one of the deadliest racial massacres in American history — a series of attacks on African-American residents of East Saint Louis that resulted in dozens of deaths and the displacement of thousands; the 1917 East St. Louis massacre is one of the pivotal events in the history of the Great Migration)); East Saint Louis is the birthplace of Miles Davis (the most important jazz musician of the 20th century — born in East St. Louis in 1926) and Jackie Joyner-Kersee (one of the greatest track and field athletes in history), a diverse Saint Clair County community with a predominantly African-American, working-class population — draws its municipal water supply from the Mississippi River via the City of East St. Louis Water Division. Water hardness in East Saint Louis measures 196.5 mg/L — classified as hard.

East Saint Louis's hard supply reflects the southwest Illinois Saint Clair County Mississippi River corridor's calcareous character. The Mississippi River at East Saint Louis carries dissolved calcium carbonate from the upper Midwest, and limited softening produces the hard 196.5 mg/L.

At 196.5 mg/L, East Saint Louis residents face regular hard water challenges. Monthly descaling and water softeners are recommended. The City of East St. Louis Water Division consistently delivers water meeting all Illinois EPA and federal EPA Safe Drinking Water Act requirements.