County Water Quality Report

St. Charles County, Missouri

2 public water systems serving 173,627 residents

Data sources: EPA SDWIS EPA ECHO EWG Tap Water Database Utility CCRs ⓘ How did we get these ratings?
County average grade
D
67/100
Utilities rated 2
Population served 173,627
🇪🇺 Would fail EU standards 2 of 2

Top water quality concerns in St. Charles County

  • Haloacetic acids (HAA9) significantly above health guidelinein 2 of 2 utilities
  • Arsenic* significantly above health guidelinein 2 of 2 utilities
  • Haloacetic acids (HAA5) significantly above health guidelinein 1 of 2 utilities
  • Total trihalomethanes (TTHMs) significantly above health guidelinein 1 of 2 utilities

All utilities in St. Charles County

Click any utility for full grade card, contaminant data, and treatment plant contact info.

C
67/100

ST CHARLES PWS

ST. CHARLES · 73,040 residents

Top concern: Haloacetic acids (HAA9) significantly above health guideline

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C
67/100

ST CHARLES COUNTY PWSD 2

O'FALLON · 100,587 residents

Top concern: Haloacetic acids (HAA9) significantly above health guideline

View report →