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St. Peters, MO Tap Water Quality 2026

Water quality report for St. Peters, MO — PFAS, lead and copper results, violation history and state inspection findings from EPA SDWIS.

A look at St. Peters's drinking water using EPA enforcement records: violations, lead and copper results, PFAS sampling and state inspection findings.

Main Utility: St Peters Pws PWSID: MO6010719 Updated: 2026 Q2
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PFAS above the federal limit at 1 of 2 sampling points

Lead was not detected and no violations are open. However, PFAS exceeds the federal limit at 1 of 2 sampling points, running as high as 1.19 times the limit.

C

St. Peters earns a C for water quality

Graded on violations, lead, and PFAS, with state inspection findings.

Lead: not detected
PFAS above the federal limit at 1 of 2 sampling points
1 violations since 2015, 0 health-based
No violations currently open
St. Peters's lead level vs. all Missouri community water systems
0 ppb5 ppb10 ppb15 ppb
Lead level: Not detected — 0% of the federal action level
✓ Lower lead than % of Missouri utilities
Population Served
41652
~19083 connections
Water Source
Surface water
Purchased from another system — SDWIS source code SWP
Active Violations
0
1 since 2015, all resolved

Lead & Copper Testing

Lead (Pb)
90th percentile of tap samples collected across the distribution system
0% of EPA action level
Not detected
Action level: 15 ppb
Lead was not detected at the 90th percentile — the result fell below the laboratory detection limit. That is not the same as an absence of lead in every tap, and older homes with lead service lines can still show higher readings.

Contaminant Violations (2015–Present)

ContaminantTypeMeasuredLimitPeriodStatus
Consumer Confidence Rule OTHER — — 2019 Resolved
Understanding violation types MCL violations mean a contaminant exceeded the federal maximum limit — the most serious type.
TT (Treatment Technique) violations mean required treatment procedures weren't followed, but don't necessarily mean contamination occurred.

Violation History

1 violations are on record since 2015, of which 0 were health-based. All have been resolved and none remain open.

About the Main Water System

Utility St Peters Pws
PWSID MO6010719
Water source Surface water — Purchased from another system — SDWIS source code SWP
Population served 41,652
Service connections 19,083
Systems serving this area 5
Regulator State primacy agency
Data through 2026 Q2 — EPA SDWIS

Frequently Asked Questions

Is St. Peters tap water safe to drink? ▼
It meets most federal standards, but PFAS exceeds the federal limit at 1 of 2 sampling points. No violations are currently open.
Does St. Peters water have PFAS? ▼
Yes. PFAS exceeds the federal limit at 1 of 2 sampling points, running as high as 1.19 times the limit. Limits are enforced on a running annual average at each sampling point, not on a single sample.
Who supplies water to St. Peters? ▼
St Peters Pws (PWSID MO6010719), one of 5 systems serving this area. Surface water. Purchased from another system — SDWIS source code SWP
When was this system last inspected? ▼
It was last inspected on 2023-03-14. Inspectors recorded 2 significant deficiencies.

What Should St. Peters Residents Do?

1
Consider a reverse-osmosis filter
Reverse osmosis removes more than 95% of PFAS. Standard carbon pitchers do not.
2
Check for a lead service line
Lead reaches tap water mainly through service lines and household plumbing. Suppliers now publish an inventory identifying lead lines.
3
Flush before drinking
If water has sat in pipes more than six hours, run the cold tap for two minutes before drinking or cooking.

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