STATE REPORT
MO
4 ALERTS
20 HEALTH VIOLATIONS
Missouri Water Quality & Safety Report
32 ZIP codes · 110 water systems · IPC plumbing code · Updated 2026-03-16
Data: EPA SDWIS, NWS, State plumbing boards, Rewiring America Last verified: 2026-03-16
32
ZIP Codes
110
Water Systems
26
ZIPs with Violations
4
Active Alerts
IPC
Plumbing Code
Overview
We track water quality, weather alerts, plumbing regulations, and energy rebates for 32 ZIP codes across Missouri, covering 110 community water systems that serve approximately 2,705,750 people.
26 of 32 ZIP codes (81%) have recorded EPA violations. 20 health-based violations have been documented.
Active Weather Alerts
4 active alerts in Missouri including 4 warnings. Severe weather can directly affect tap water quality — flooding, power outages, and infrastructure damage may lead to boil-water advisories.
| Alert | Severity | Areas |
|---|---|---|
| High Wind Warning | Severe | Buchanan; Delaware; Dubuque; Benton; Linn; Jones; Jackson… |
| High Wind Warning | Severe | Worth; Gentry; Harrison; Mercer; Putnam; Schuyler; De Kal… |
| Freeze Warning | Moderate | Clay; Greene; Craighead; Poinsett; Mississippi; Cross; Cr… |
| Freeze Warning | Moderate | Clay; Greene; Craighead; Poinsett; Mississippi; Cross; Cr… |
Plumbing Regulations
Missouri follows the International Plumbing Code (2018 edition).
- Plumbing code: IPC (2018)
- Homeowner DIY: Licensed plumber required
- Water heater permit: Required
- Annual backflow test: Required
Areas with Most Violations
| ZIP Code | City | Safety Score | Violations | Health-Based | System |
|---|---|---|---|---|---|
| 64068 | Liberty | — | 89 | 0 | LIBERTY PWS |
| 63016 | Cedar Hill | — | 35 | 4 | JEFFERSON CO PWSD 8 |
| 63013 | Beaufort | — | 29 | 2 | CIRCLE C MHP |
| 64002 | Lees Summit | — | 16 | 0 | LEES SUMMIT PWS |
| 63701 | Cape Girardeau | — | 15 | 1 | CAPE GIRARDEAU PWS |
| 65672 | Hollister | — | 11 | 0 | HOLLISTER PWS |
| 63019 | Crystal City | — | 10 | 10 | CRYSTAL CITY PWS |
| 63025 | Eureka | — | 9 | 0 | JEFFERSON COUNTY PWSD 2 |
| 65615 | Branson | — | 8 | 0 | BRANSON PWS |
| 63366 | O Fallon | — | 5 | 0 | ST CHARLES COUNTY PWSD 2 |
Areas with No Violations
| ZIP Code | City | Safety Score | System | Population |
|---|---|---|---|---|
| 63005 | Chesterfield | — | MO AMERICAN ST LOUIS ST CHARLES COUNTIES | 1,111,000 |
| 63012 | Barnhart | — | JEFFERSON CO CONS PWSD C 1 | 37,000 |
| 63048 | Herculaneum | — | HERCULANEUM PWS | 4,227 |
| 63049 | High Ridge | — | ANTIRE VALLEY SUBD | 260 |
| 64776 | Osceola | — | OSCEOLA PWS | 947 |
| 65101 | Jefferson City | — | MO AMERICAN JEFFERSON CITY DISTRICT | 30,075 |
Lead & Copper
- 0 ZIP codes exceed the EPA lead action level
Radon Risk
- High risk (Zone 1): 0 ZIP codes (0%)
- Moderate risk (Zone 2): 0 ZIP codes
- Low risk (Zone 3): 0 ZIP codes
All 32 ZIP Codes in Missouri
- 63010 (Arnold) — 4 violations
- 63012 (Barnhart)
- 63013 (Beaufort) — 29 violations ⚠
- 63014 (Berger) — 1 violation
- 64013 (Blue Springs) — 4 violations
- 65615 (Branson) — 8 violations
- 63701 (Cape Girardeau) — 15 violations ⚠
- 63016 (Cedar Hill) — 35 violations ⚠
- 63005 (Chesterfield)
- 65201 (Columbia) — 2 violations
- 63019 (Crystal City) — 10 violations ⚠
- 63020 (De Soto) — 3 violations
- 63023 (Dittmer) — 3 violations
- 63025 (Eureka) — 9 violations
- 63026 (Fenton) — 3 violations ⚠
- 63028 (Festus) — 1 violation
- 63037 (Gerald) — 2 violations
- 63048 (Herculaneum)
- 63049 (High Ridge)
- 65672 (Hollister) — 11 violations
- 64050 (Independence) — 3 violations
- 65101 (Jefferson City)
- 64801 (Joplin) — 1 violation
- 64101 (Kansas City) — 2 violations
- 64002 (Lees Summit) — 16 violations
- 64068 (Liberty) — 89 violations
- 63366 (O Fallon) — 5 violations
- 64776 (Osceola)
- 63901 (Poplar Bluff) — 2 violations ⚠
- 65401 (Rolla) — 5 violations
- 65301 (Sedalia) — 2 violations
- 65801 (Springfield) — 5 violations
Data Sources
- Water quality: EPA Safe Drinking Water Information System (SDWIS)
- Weather alerts: National Weather Service (NWS)
- Regulations: State plumbing boards, ICC, IAPMO
- Rebates: Rewiring America
Updated daily.