MO AMERICAN ST LOUIS ST CHARLES COUNTIES

CHESTERFIELD, MO · ~1,111,000 people served

Check your exact address → CHESTERFIELD overview

100

Excellent

PurityRadar safety score

PWSID

MO6010716

State

Missouri

City

CHESTERFIELD

Population served

1,111,000

Primary source

Surface water

Score history

No change since tracking began Jun 18, 2026.

Jun 18, 2026 · score 100 Jun 18, 2026 · score 100

2 score updates logged since tracking began Jun 18, 2026. Each future EPA re-score adds a point.

PFAS & contaminant readings

Latest detections from EPA’s UCMR5 monitoring (through Dec 2024). Levels in parts per trillion (ppt).

Lithium

62,600 ppt

limit —

No federal limit

PFBA

5 ppt

limit —

No federal limit

Violations & enforcement

Violations on record

Unaddressed

Health-based

Enforcement actions

From EPA ECHO (SDWIS), most recent enforcement Dec 2010. Official EPA record →

Treatment technique · EPA contaminant 0300 health-based began Jun 2010 Resolved

Treatment technique · EPA contaminant 0300 health-based began Aug 2007 Resolved

Recent enforcement actions

State action · SOX Dec 2010
State action · SFJ Jul 2010
State action · SIE Jul 2010
State action · SIF Jun 2010
State action · SOX Jun 2008
State action · SIF Oct 2007
State action · SIE Sep 2007
State action · SIA Sep 2007

Area water-quality monitoring

Environmental monitoring (rivers, wells, intakes) recorded in this system’s service area in the EPA/USGS Water Quality Portal since 2018 — source/ambient water, not finished tap water. Context for the watershed, not a reading from your tap.

ContaminantMedian · max · samples

Nitrate

2 stations · latest Sep 2024

0.00875 · max 1.23 mg/L · 26

Source: Water Quality Portal (EPA/USGS/state agencies). Values are as-reported and aren’t health thresholds.

This profile is built from EPA public records for system MO6010716 — SDWIS violations and UCMR5 PFAS sampling. The score is system-level and can’t account for your home’s plumbing (older pipes can add lead at the tap). For health decisions, check your exact address, read the utility’s Consumer Confidence Report, and confirm with your provider.