- EPA's UCMR 5 testing looked for 30 contaminants here and found 2.
- Lithium: found in 16 of 24 samples, average 36.2 µg/L, highest 86.8 µg/L (EPA UCMR 5 testing, Mar 2024–Dec 2024)
- PFBA (a PFAS): found in 2 of 24 samples, average 0.40 ppt, highest 5.1 ppt (EPA UCMR 5 testing, Mar 2024–Dec 2024)
- Lead: 9 in 10 homes tested came in at or below 0 ppb, at or below EPA's 15 ppb action level (latest EPA result for a testing period that ran on or after July 1, 2021: Jan 1, 2023–Dec 31, 2025). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
Public EPA test results
What EPA records show for MO American St Louis St Charles Counties
EPA system ID MO6010716 · serves St. Charles County, MO · about 1,111,000 people (EPA records)
Here's what EPA has on file for this water system: its testing for newer contaminants like PFAS (UCMR 5), lead testing and violations. It's not a test of your tap, and there's no Water Score here.
Public EPA test results
MO American St Louis St Charles Counties (EPA MO6010716)
What EPA records show for MO American St Louis St Charles Counties, as of October 14, 2026
We found no health-standard violations in EPA's records for this system (MO6010716) since July 1, 2021, as of October 14, 2026.
Source: EPA ECHO record for MO American St Louis St Charles Counties (SDWIS). Data as of October 14, 2026.
Lead: 9 in 10 homes tested came in at or below 0 ppb, at or below EPA's 15 ppb action level (latest EPA result for a testing period that ran on or after July 1, 2021: Jan 1, 2023–Dec 31, 2025). This is one number for the whole water system, from homes the utility tested. It isn't a result for your home.
EPA's UCMR 5 testing looked for 30 contaminants here and found 2.
PFOA and PFOS were not detected at or above EPA's reporting level in EPA's UCMR 5 testing.
Source: EPA records (SDWIS, UCMR 5). SDWIS: data as of Oct 14, 2026. EPA UCMR 5 data, samples through June 2026.
Your water bill names your utility.
Does MO American St Louis St Charles Counties use chloramine?
We didn't find chloramine in MO American St Louis St Charles Counties's EPA treatment records. That's not a complete list; your utility's annual water quality report says which disinfectant it uses.
What EPA records show for this system
Reported results in EPA records (data as of Oct 14–15, 2026)