United States Last reviewed: August 28, 2026

Missouri Tap Water Quality

Q: Is tap water safe to drink in Missouri?

Yes in St. Louis, Kansas City, Springfield, and the major systems, all EPA-compliant. Small Ozark and Bootheel systems account for most advisories.

Q: Does the Old Lead Belt affect drinking water?

Mining-district soils and some groundwater in southeast Missouri carry elevated lead, affecting private wells and a few small systems; public systems there treat and monitor accordingly.

Q: Why do Ozark wells need extra care?

Karst limestone funnels surface water (and contamination) into aquifers within hours; spring-fed and shallow-well supplies need disinfection and post-storm caution.

about 1,390

Community water systems

City reports on this site

Tracked contaminants

August 28, 2026

Data reviewed

Check a Missouri ZIP Code

Overview

St. Louis and Kansas City both treat Missouri/Mississippi River water at scale and hold strong compliance records; Missouri American Water's St. Louis County operation is one of the largest investor-owned systems in the country. Springfield and the Ozarks lean on wells and reservoirs.

Missouri's mining legacy (the Old Lead Belt) left elevated lead in some southeast groundwater and soils, karst geology makes Ozark springs quick to contaminate, and small-system violations (bacteria, DBPs, occasional radium) track the state's large rural footprint.

Common Contaminants in Missouri

Lead

Legacy from both mining districts and old urban service lines; St. Louis and KC run corrosion control and replacement programs

Bacteria in karst systems

Ozark springs and shallow wells are vulnerable to rapid surface intrusion after storms

Radium

Naturally occurring exceedances in scattered small groundwater systems

Violations & Compliance

The metro systems are reliably compliant; most violations occur in small rural systems. The state uses regionalization grants to fold struggling systems into stronger neighbors.