Tap water in Williamstown, MO — ZIP 63301
3 public water systems serving about 139,536 people. PFAS "forever chemicals" have been detected here.
C
Fair
PFAS detected: at least one system serving this ZIP reported PFAS in EPA UCMR 5
testing. Levels and the 2024 federal limits are shown per system below.
Water systems serving 63301
St Charles Pws
PWSID MO6010707 · serves 78,961 ·
surface water
0 health-based / 1 total violations (5 yrs)
St Peters Pws
PWSID MO6010719 · serves 52,575 ·
surface water
0 health-based / 0 total violations (5 yrs)
· PFAS up to 10.6 ppt — above federal limit
Clark County Cons Pwsd 1
PWSID MO2024138 · serves 8,000 ·
groundwater
0 health-based / 2 total violations (5 yrs)
Grades summarize EPA SDWIS violation records (last 5 years) and UCMR 5 PFAS results. They are informational, not a health determination. Methodology