Missouri Water Quality
According to EPA Safe Drinking Water Information System (SDWIS), Missouri has 1,688 active community water systems in this extract. PlainEnviro's health-based slice lists 6,737 violation records across 50 systems with at least one such row. These are historical EPA registry counts, not a statewide drinkability score.
Health-based violation records for 1,688 community water systems in Missouri. Source: EPA Safe Drinking Water Information System (SDWIS).
Water Systems with Most Health-Based Records
| # | Water System | Health-Based Records | Health |
|---|---|---|---|
| 1 | CASSIE WATER SYSTEM Des Peres | 347 | Yes |
| 2 | FRANKLIN WATER SYSTEMS 3 Des Peres | 322 | Yes |
| 3 | HOWARD WATER COOP Des Peres | 188 | Yes |
| 4 | SOUTH SILVER CREEK I II & III Des Peres | 180 | Yes |
| 5 | ABRAXAS UTILITIES Des Peres | 171 | Yes |
| 6 | TERRE DU LAC Des Peres | 162 | Yes |
| 7 | WESTLAKE MEADOWS SUBDIVISION Cape Girardeau | 150 | Yes |
| 8 | SILEX PWS Silex | 146 | Yes |
| 9 | MAYSVILLE PWS Maysville | 131 | Yes |
| 10 | SOUTH COUNCIL CREEK 2 Des Peres | 128 | Yes |
| 11 | CS CITRUS PARK WATER COMPANY Des Peres | 126 | Yes |
| 12 | MOSBY PWS Mosby | 126 | Yes |
| 13 | LANAGAN PWS Lanagan | 122 | Yes |
| 14 | CS EL PRADO WATER COMPANY Des Peres | 118 | Yes |
| 15 | MAGNOLIA-SPRING CREEK SUBDIVISION Des Peres | 115 | Yes |
| 16 | COUNCIL CREEK VILLAGE Des Peres | 114 | Yes |
| 17 | LIVE OAK HILLS SUBDIVISION Des Peres | 110 | Yes |
| 18 | TEXAS LANDING UTILITIES Des Peres | 106 | Yes |
| 19 | MONROE CITY PWS Monroe | 93 | Yes |
| 20 | VISTA VERDE WATER SYSTEMS Des Peres | 92 | Yes |
| 21 | LEADWOOD PWS Leadwood | 91 | Yes |
| 22 | LA PLAYA SUBDIVISION WATER SYSTEM Des Peres | 91 | Yes |
| 23 | CLUBB VILLA SENIOR LIVING Defiance | 67 | Yes |
| 24 | CSWR SOUTHWEST GARDEN WATER Des Peres | 66 | Yes |
| 25 | FREDERICKTOWN PWS Fredricktown | 63 | Yes |
| 26 | CS LAKE VERDE WATER COMPANY Des Peres | 56 | Yes |
| 27 | MO AMERICAN GARDEN CITY Joplin | 55 | Yes |
| 28 | LOUISIANA PWS Louisiana | 54 | Yes |
| 29 | CS TIERRA MESA ESTATES WATER COMPANY Des Peres | 47 | Yes |
| 30 | EL PINON ESTATES WATER SYSTEM Des Peres | 46 | Yes |
| 31 | CS RANCHEROS BONITOS WATER COMPANY Des Peres | 45 | Yes |
| 32 | BONNE TERRE PWS Bonne Terre | 43 | Yes |
| 33 | FARMINGTON PWS Farmington | 42 | Yes |
| 34 | OZARK COUNTY PWSD 1 Theodosia | 40 | Yes |
| 35 | BLODGETT PWS Blodgett | 38 | Yes |
| 36 | CLEVELAND PWS Cleveland | 37 | Yes |
| 37 | BATES COUNTY PWSD 2 Amsterdam | 33 | Yes |
| 38 | DS WATER COMPANY Des Peres | 32 | Yes |
| 39 | KING CITY PWS King City | 32 | Yes |
| 40 | MO AMERICAN IRONTON Chesterfield | 32 | Yes |
| 41 | CRAZY HORSE RANCH WATER Des Peres | 31 | Yes |
| 42 | POPLAR BLUFF PWS Poplar Bluff | 30 | Yes |
| 43 | HUBERT WATSON SUBDIVISION Des Peres | 30 | Yes |
| 44 | ARROW ROCK PWS Arrow Rock | 29 | Yes |
| 45 | RALLS COUNTY PWSD 1 Hannibal | 28 | Yes |
| 46 | CS MOHAWK UTILITY COMPANY Des Peres | 27 | Yes |
| 47 | CS WHITE HILLS WATER COMPANY UNIT 1 Des Peres | 26 | Yes |
| 48 | LAF JO SALINE COUNTY CONS PWSD 2 Higginsville | 26 | Yes |
| 49 | POTOSI PWS Potosi | 26 | Yes |
| 50 | RIPLEY COUNTY PWSD 1 WEST Doniphan | 24 | Yes |
Most Common Contaminants in Missouri
| Contaminant | Violations | Systems Affected |
|---|---|---|
| TTHM | 1,342 | 125 |
| Combined Radium (-226 and -228) | 1,039 | 27 |
| Gross Alpha, Excl. Radon and U | 881 | 28 |
| Groundwater Rule | 572 | 199 |
| Long Term 2 Enhanced Surface Water Treatment Rule | 415 | 18 |
| Arsenic | 345 | 11 |
| Nitrate | 312 | 7 |
| Coliform (TCR) | 308 | 84 |
| Revised Total Coliform Rule | 288 | 122 |
| Total Haloacetic Acids (HAA5) | 285 | 29 |
| Fluoride | 278 | 4 |
| Interim Enhanced Surface Water Treatment Rule | 163 | 12 |
| Stage 1 Disinfectants and Disinfection Byproducts Rule | 130 | 66 |
| CARBON, TOTAL | 124 | 10 |
| Combined Uranium | 84 | 3 |
Cities with Water Quality Issues
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About This Data
Water quality data is from the EPA Safe Drinking Water Information System (SDWIS). Health-based violations include Maximum Contaminant Level (MCL) and Treatment Technique (TT) violations. Only community water systems (CWS) in Missouri are included.
Source: U.S. Environmental Protection Agency, SDWIS Federal Reporting Services
Read our methodology - how this data is sourced, computed, and verified.