Is St Charles County Pwsd 2 Tap Water Safe? Quality Report

Water source: SWP
Ownership: Local government
Counties served: St. Charles

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.

health-based violations

violations on file

still open

Violation	Type	Status	Period
MCL	Health-based	Resolved	2007-09-01 → 2007-09-30
MCL	Health-based	Resolved	2007-09-01 → 2007-09-30
MCL	Health-based	Resolved	2007-09-01 → 2007-09-30
MCL	Health-based	Resolved	2007-09-01 → 2007-09-30
MCL	Health-based	Resolved	1996-12-01 → 1996-12-31
MCL	Health-based	Resolved	1996-12-01 → 1996-12-31
MCL	Health-based	Resolved	1996-12-01 → 1996-12-31
MCL	Health-based	Resolved	1996-12-01 → 1996-12-31
MCL	Health-based	Resolved	1996-12-01 → 1996-12-31
MR	Monitoring	Resolved	2025-06-01 → 2025-06-30

PFAS detected

PFAS are industrial “forever chemicals”. These are the EPA's latest nationwide test results (2023–2025).

Contaminant	Max	Detection rate	Period
Pfba	0.0065 µg/L	2/9	2025

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 95th percentile of this system's samples — over 100% is worth reading, but is not by itself a violation. Where a single sample came in higher than that percentile, it is noted under the bar. Formal violations are listed separately.

Contaminant	Level vs EPA limit	Detection rate	Source	Period
Bromodichloromethane	8.97 µg/L No EPA limit set worst single sample: 12.3 µg/L	163/166	SYR4	2012–2019
Chloroform	25.45 µg/L No EPA limit set worst single sample: 50.1 µg/L	163/166	SYR4	2012–2019
TTHM	37.695 µg/L 47% of the EPA limit 80 µg/L worst single sample: 53 µg/L	160/161	SYR4	2012–2019
Dichloroacetic Acid	29.02 µg/L No EPA limit set worst single sample: 36.3 µg/L	159/161	SYR4	2012–2019
Trichloroacetic Acid	5.1875 µg/L No EPA limit set worst single sample: 10.1 µg/L	152/161	SYR4	2012–2019
Total Haloacetic Acids (HAA5)	32.56 µg/L 54% of the EPA limit 60 µg/L worst single sample: 41.7 µg/L	149/161	SYR4	2012–2019
Dibromochloromethane	4.556 µg/L No EPA limit set worst single sample: 5.03 µg/L	129/166	SYR4	2012–2019
Copper	64.215 µg/L 4.9% of the EPA limit 1300 µg/L worst single sample: 145 µg/L	92/94	SYR4	2013–2019
Dibromoacetic Acid	1.871 µg/L No EPA limit set worst single sample: 2.14 µg/L	43/161	SYR4	2012–2019
Monobromoacetic Acid	8.9625 µg/L No EPA limit set worst single sample: 10.4 µg/L	26/161	SYR4	2012–2019
Nitrate-Nitrite	1442.5 µg/L 14% of the EPA limit 10000 µg/L worst single sample: 1610 µg/L	26/36	SYR4	2012–2019
Bromoform	0.7285 µg/L No EPA limit set worst single sample: 0.7300 µg/L	24/166	SYR4	2012–2019
Chromium	2.404 µg/L 2.4% of the EPA limit 100 µg/L worst single sample: 2.62 µg/L	17/17	SYR4	2013–2017
Lead	0.0 mg/L 0% of the EPA limit 0.0150 mg/L	17/17	LCR	2025
Lead	3.45 µg/L 23% of the EPA limit 15 µg/L worst single sample: 3.73 µg/L	15/94	SYR4	2013–2019
Combined Radium (-226 And -228)	3.245 pCi/L 65% of the EPA limit 5 pCi/L worst single sample: 3.3 pCi/L	12/13	SYR4	2014–2019
Gross Alpha, Excl. Radon And U	12.05 pCi/L 80% of the EPA limit 15 pCi/L worst single sample: 15 pCi/L	11/12	SYR4	2014–2015
Lithium	47.5 µg/L No EPA limit set	9/9	UCMR-5	2025
Barium	142.4 µg/L 7.1% of the EPA limit 2000 µg/L worst single sample: 147 µg/L	5/5	SYR4	2014–2017
Fluoride	632 µg/L 16% of the EPA limit 4000 µg/L worst single sample: 640 µg/L	5/5	SYR4	2014–2017
Atrazine	0.3300 µg/L 11% of the EPA limit 3 µg/L	1/3	SYR4	2016
Monochloroacetic Acid	9.7 µg/L No EPA limit set	1/161	SYR4	2012–2019

79 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-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalArsenicBhc-GammaBenzeneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneCombined UraniumDichloromethaneDalaponDinosebEthylene DibromideEndrinEthylbenzeneHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorNetfosaaNfdhaNmefosaaOxamylPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: WRIGHT, JIM
Phone: 636-385-5197
Email: [email protected]

Frequently asked questions about St Charles County Pwsd 2

Is St Charles County Pwsd 2 tap water safe to drink?

EPA monitoring detected 23 contaminants in St Charles County Pwsd 2'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 St Charles County Pwsd 2's water?

EPA monitoring detected Bromodichloromethane, Chloroform, TTHM, Dichloroacetic Acid, Trichloroacetic Acid, and others. The full list with the level and data source for each is above.

How many people does St Charles County Pwsd 2 serve?

St Charles County Pwsd 2 reports serving 100,587 people in Missouri, per its EPA record.

Has St Charles County Pwsd 2 had any water quality violations?

The EPA has 17 violations on file for St Charles County Pwsd 2, of which 9 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.