PlainWater
Counties → Missouri

St. Louis County, Missouri

Water Systems
23
Population Served
1,145,619
Total Violations
1,825
365 health-based
PFAS Detected
2
of 2 tested

Violation Analysis

95.7%
Systems with Violations
79.3
Avg Violations per System
20.0%
Health-Based Violations

Water Source Types

GW
20 systems (87%)
SW
3 systems (13%)

PFAS Contamination

2
Systems Tested
2
PFAS Detected
100.0%
Detection Rate

PFAS (per- and polyfluoroalkyl substances) are persistent chemicals found in drinking water. The EPA has set enforceable limits for several PFAS compounds under UCMR5 monitoring.

Compliance Snapshot

St. Louis Missouri water systems by violation status, EPA SDWIS records.

No violations on record (1) One or more violations (22)

Violation history is cumulative, many flagged systems have already returned to compliance. Detail pages show per-system context.

Water Systems

System Name Population Violations PFAS
MO American St Louis St Charles Counties 1,111,000 9 Detected
Kirkwood PWS 28,000 0 Clean
Six Flags St Louis 3,200 18 -
MO Eastern Correctional Center 1,100 28 -
Rockwoods Reservation 550 23 -
Babler State Park 500 37 -
MO American Pevely Farms 343 25 -
Terrisan 240 5 -
Greensfelder County Park 100 58 -
Crescent Farms Golf Club 100 356 -
Hidden Valley Golf and Ski 100 23 -
Wyman 50 97 -
Jay Henges Range 50 101 -
Paradise Valley Golf & Country Club 50 156 -
Holiday Inn at Six Flags 30 67 -
West Tyson County Park 30 62 -
Tyson Research Center 26 59 -
Alta Convenience 6524 25 259 -
Lone Elk County Park 25 50 -
Aberdeen Golf Club 25 104 -
Jellystone Park Cmpgrd 25 191 -
Marianist Retreat Center 25 53 -
World Bird Sanctuary 25 44 -

Other Counties in Missouri

Cass County
31 systems · 625,744 served · 1,771 violations
Jackson County
23 systems · 405,266 served · 559 violations
St. Charles County
54 systems · 310,776 served · 2,706 violations
St. Louis city County
1 systems · 304,709 served · 27 violations
Greene County
82 systems · 265,439 served · 7,132 violations
Boone County
13 systems · 228,201 served · 462 violations

Drinking Water Guides

Frequently Asked Questions

How many water violations are in St. Louis County? ▼
St. Louis County has 1,825 total drinking water violations across 23 water systems, of which 365 are health-based violations. 95.7% of systems have at least one violation.
How many people get water from St. Louis County systems? ▼
Water systems in St. Louis County serve approximately 1,145,619 people through 23 public water systems.
Has PFAS been detected in St. Louis County water? ▼
Of 2 water systems tested for PFAS in St. Louis County, 2 had PFAS detected (100.0% detection rate).
What types of water sources supply St. Louis County? ▼
Water systems in St. Louis County use GW (20 systems), SW (3 systems) as their primary water sources.
Are health-based violations serious? ▼
Health-based violations indicate that drinking water exceeded Maximum Contaminant Levels (MCLs) set by the EPA or failed treatment technique requirements. 20.0% of St. Louis County's violations are health-based. Not all violations indicate immediate health risk, but they require corrective action.
Data Sources & Methodology

Drinking water violation data from the EPA Safe Drinking Water Information System (SDWIS). PFAS testing data from the UCMR5 monitoring program. SDWIS tracks all public water systems regulated under the Safe Drinking Water Act.

Violations are categorized as health-based (Maximum Contaminant Level exceedances, treatment technique failures) or monitoring/reporting violations. Not all violations indicate an immediate health risk.

Read our methodology - how this data is sourced, computed, and verified.

Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This page draws directly on EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.