Is Coupeville Town of Tap Water Safe? Quality Report

Water source: Ground water
Ownership: Local government
Counties served: Island

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
MON	Monitoring	Resolved	2020-10-01 → 2020-10-31
Other	Monitoring	Resolved	2015-07-01
MR	Monitoring	Archived	2009-01-01 → 2009-12-31
MR	Monitoring	Archived	2009-01-01 → 2009-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31
MR	Monitoring	Archived	2008-01-01 → 2010-12-31

PFAS detected

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

Contaminant	Max	Detection rate	Period
Pfhxa	0.0170 µg/L	2/2	2025
Pfpea	0.0120 µg/L	2/2	2025
Pfba	0.0053 µg/L	1/2	2025
PFBS	0.0067 µg/L	1/2	2025
Pfhpa	0.0033 µg/L	1/2	2025
PFHXS	0.0038 µg/L	1/2	2025
PFOA	0.0098 µg/L	1/2	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
Nitrate	1928 µg/L 19% of the EPA limit 10000 µg/L worst single sample: 2460 µg/L	40/72	SYR4	2012–2019
Bromodichloromethane	8.92 µg/L No EPA limit set worst single sample: 9 µg/L	17/21	SYR4	2013–2019
Bromoform	18.4 µg/L No EPA limit set worst single sample: 20.4 µg/L	17/21	SYR4	2013–2019
TTHM	42.02 µg/L 53% of the EPA limit 80 µg/L worst single sample: 44.5 µg/L	17/17	SYR4	2013–2019
Dibromochloromethane	16.675 µg/L No EPA limit set worst single sample: 17.8 µg/L	16/20	SYR4	2013–2019
Chloroform	3.19 µg/L No EPA limit set worst single sample: 3.4 µg/L	15/21	SYR4	2012–2019
Lead	0.0035 mg/L 23% of the EPA limit 0.0150 mg/L	12/12	LCR	2025
Total Haloacetic Acids (HAA5)	6.26 µg/L 10% of the EPA limit 60 µg/L worst single sample: 6.5 µg/L	9/17	SYR4	2013–2019
Dibromoacetic Acid	4.36 µg/L No EPA limit set worst single sample: 4.5 µg/L	8/17	SYR4	2013–2019
Arsenic	8.175 µg/L 82% of the EPA limit 10 µg/L worst single sample: 8.3 µg/L	6/6	SYR4	2012–2019
Gross Beta Particle Activity	9.982 pCi/L No EPA limit set worst single sample: 10.1 pCi/L	5/5	SYR4	2018
Nitrate-Nitrite	1700 µg/L 17% of the EPA limit 10000 µg/L	4/6	SYR4	2012–2019
Monobromoacetic Acid	1.87 µg/L No EPA limit set worst single sample: 1.9 µg/L	3/17	SYR4	2013–2019
Barium	253 µg/L 13% of the EPA limit 2000 µg/L worst single sample: 260 µg/L	2/6	SYR4	2012–2019
Dichloroacetic Acid	1.99 µg/L No EPA limit set worst single sample: 2 µg/L	2/17	SYR4	2013–2019
Fluoride	628 µg/L 16% of the EPA limit 4000 µg/L worst single sample: 640 µg/L	2/6	SYR4	2012–2019
Combined Radium (-226 And -228)	0.5000 pCi/L 10% of the EPA limit 5 pCi/L	1/1	SYR4	2012
Lead	1.5 µg/L 10% of the EPA limit 15 µg/L	1/7	SYR4	2012–2019

81 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, TotalAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndrinEthylbenzeneHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitritePfdaPfdoaPfeesaPfhpsPfmbaPfmpaPFNAPFOSPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: Joseph Grogan

Frequently asked questions about Coupeville Town of

Is Coupeville Town of tap water safe to drink?

EPA monitoring detected 25 contaminants in Coupeville Town of'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 Coupeville Town of's water?

EPA monitoring detected Nitrate, Bromodichloromethane, Bromoform, TTHM, Dibromochloromethane, and others. The full list with the level and data source for each is above.

How many people does Coupeville Town of serve?

Coupeville Town of reports serving 4,142 people in Washington, per its EPA record.

Has Coupeville Town of had any water quality violations?

The EPA has 96 violations on file for Coupeville Town of, of which 0 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.