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Tap water quality report

Mo American St Louis St Charles Counties

EPA monitoring tested this supplier for 108 contaminants and detected 34. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

108
contaminants tested
34
detected
1,111,000
people served
8
health-based violations
Missouri rankingsLead in MissouriPFAS in Missouri
Water source
Surface water
Ownership
Private
Counties served
St. Charles, St. Louis

Compliance record

Formal violations the EPA has on file for this supplier. A health-based violation means a contaminant limit or a required treatment was breached; the rest are monitoring or reporting failures — still violations, but not a measured health risk.

8
health-based violations
9
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2010-06-01 → 2010-06-30
TT Health-based Resolved 2010-06-01 → 2010-06-30
TT Health-based Resolved 2010-06-01 → 2010-06-30
TT Health-based Resolved 2010-06-01 → 2010-06-30
TT Health-based Resolved 2007-08-01 → 2007-08-31
TT Health-based Resolved 2007-08-01 → 2007-08-31
TT Health-based Resolved 2007-08-01 → 2007-08-31
TT Health-based Resolved 2007-08-01 → 2007-08-31
MR Monitoring Archived 2005-06-01 → 2005-06-30

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).
ContaminantMaxDetection ratePeriod
Pfba 0.0051 µg/L 2/24 2024

Other contaminants detected

Each bar shows the measured level as a share of the EPA limit: green is well under, amber is close to it, red is over. For lead and copper the limit applies to exactly the 90th-percentile figure shown, so red there means a real exceedance. For everything else the limit applies to a running annual average while the figure is the single worst sample on record — over 100% is worth reading, but is not by itself a violation. Formal violations are listed separately.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Chloroform
96.5 µg/L
No EPA limit set
 575/575 SYR4 2012–2019
Dichloroacetic Acid
44.7 µg/L
No EPA limit set
 570/570 SYR4 2012–2019
TTHM
99.9 µg/L 125%
of the EPA limit, in the worst sample — 80 µg/L
 570/570 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
54.3 µg/L 90%
of the EPA limit 60 µg/L
 570/570 SYR4 2012–2019
Bromodichloromethane
16.7 µg/L
No EPA limit set
 521/575 SYR4 2012–2019
Trichloroacetic Acid
7.8 µg/L
No EPA limit set
 421/570 SYR4 2012–2019
Dibromochloromethane
8.1 µg/L
No EPA limit set
 320/575 SYR4 2012–2019
Monobromoacetic Acid
6.6 µg/L
No EPA limit set
 168/570 SYR4 2012–2019
Fluoride
800 µg/L 20%
of the EPA limit 4000 µg/L
 148/148 SYR4 2012–2019
Nitrate
3450 µg/L 35%
of the EPA limit 10000 µg/L
 120/120 SYR4 2012–2019
Dibromoacetic Acid
3.5 µg/L
No EPA limit set
 111/570 SYR4 2012–2019
Atrazine
0.7000 µg/L 23%
of the EPA limit 3 µg/L
 79/160 SYR4 2012–2019
Nitrate-Nitrite
3450 µg/L 35%
of the EPA limit 10000 µg/L
 71/71 SYR4 2012–2019
Monochloroacetic Acid
4.7 µg/L
No EPA limit set
 68/570 SYR4 2012–2019
Chromium
2.6 µg/L 2.6%
of the EPA limit 100 µg/L
 45/105 SYR4 2012–2019
Lead
10 µg/L 67%
of the EPA limit 15 µg/L
 28/215 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 19/19 LCR 2025
2,4-D
0.5000 µg/L 0.7%
of the EPA limit 70 µg/L
 17/106 SYR4 2012–2019
Bromoform
1.4 µg/L
No EPA limit set
 16/575 SYR4 2012–2019
Lithium
86.8 µg/L
No EPA limit set
 16/24 UCMR-5 2024
Copper
782 µg/L 60%
of the EPA limit 1300 µg/L
 13/215 SYR4 2012–2019
Selenium
3 µg/L 6%
of the EPA limit 50 µg/L
 13/65 SYR4 2012–2019
Antimony, Total
0.5000 µg/L 8.3%
of the EPA limit 6 µg/L
 9/65 SYR4 2012–2019
Arsenic
1.74 µg/L 17%
of the EPA limit 10 µg/L
 8/65 SYR4 2012–2019
Barium
42.5 µg/L 2.1%
of the EPA limit 2000 µg/L
 5/65 SYR4 2012–2019
Diquat
0.6000 µg/L 3%
of the EPA limit 20 µg/L
 4/105 SYR4 2012–2019
Di(2-ethylhexyl) Phthalate
1.1 µg/L 18%
of the EPA limit 6 µg/L
 2/155 SYR4 2012–2019
Hexachlorocyclopentadiene
0.1000 µg/L 0.2%
of the EPA limit 50 µg/L
 2/156 SYR4 2012–2019
Benzo(A)Pyrene
0.0400 µg/L 20%
of the EPA limit 0.2000 µg/L
 1/156 SYR4 2012–2019
Dichloromethane
1.1 µg/L 22%
of the EPA limit 5 µg/L
 1/61 SYR4 2012–2019
Ethylene Dibromide
0.0200 µg/L 40%
of the EPA limit 0.0500 µg/L
 1/110 SYR4 2012–2019
Nitrite
100 µg/L 10%
of the EPA limit 1000 µg/L
 1/60 SYR4 2012–2019
Picloram
0.2000 µg/L 0%
of the EPA limit 500 µg/L
 1/106 SYR4 2012–2019
74 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,4,5-TP4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaBhc-GammaBenzeneBeryllium, TotalBromateChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneDalaponDi(2-ethylhexyl) AdipateDinosebEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
LANE, SHELLEY
Phone
314-548-0199
Email
Shelley.Lane@amwater.com

Frequently asked questions about Mo American St Louis St Charles Counties

Is Mo American St Louis St Charles Counties tap water safe to drink?

EPA monitoring detected 34 contaminants in Mo American St Louis St Charles Counties's water. A detection isn't the same as a violation — most levels are within federal limits. See each level and source above, and the utility's annual Consumer Confidence Report for its official compliance status.

What contaminants were detected in Mo American St Louis St Charles Counties's water?

EPA monitoring detected Chloroform, Dichloroacetic Acid, TTHM, Total Haloacetic Acids (HAA5), Bromodichloromethane, and others. The full list with the level and data source for each is above.

How many people does Mo American St Louis St Charles Counties serve?

Mo American St Louis St Charles Counties reports serving 1,111,000 people in Missouri, per its EPA record.

Has Mo American St Louis St Charles Counties had any water quality violations?

The EPA has 9 violations on file for Mo American St Louis St Charles Counties, of which 8 are health-based (a contaminant limit or required treatment was breached) and 0 remain open. The rest are monitoring or reporting failures.

Where does this data come from?

Every figure is official EPA drinking-water monitoring — the Lead & Copper Rule, the UCMR-5 nationwide testing program, and the EPA Six-Year Review — not our own testing. Each number is labelled with its source and period.