Is Valley of the Moon Water District Tap Water Safe? Quality Report

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

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
MR	Monitoring	Resolved	2020-01-01 → 2020-12-31
MR	Monitoring	Resolved	2020-01-01 → 2020-12-31
MR	Monitoring	Resolved	2020-01-01 → 2020-12-31
MR	Monitoring	Resolved	2020-01-01 → 2020-12-31
Other	Monitoring	Archived	1989-06-01 → 1989-06-30
Other	Monitoring	Archived	1988-11-01 → 1988-11-30

PFAS detected

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

Contaminant	Max	Detection rate	Period
PFBS	0.0042 µg/L	3/14	2025
Pfhxa	0.0036 µg/L	2/14	2025
PFHXS	0.0042 µg/L	2/14	2025
PFOA	0.0052 µg/L	2/14	2025
PFOS	0.0054 µg/L	1/14	2025
Pfpea	0.0030 µg/L	1/14	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
TTHM	27.7 µg/L 35% of the EPA limit 80 µg/L worst single sample: 38 µg/L	127/127	SYR4	2012–2019
Bromodichloromethane	7.975 µg/L No EPA limit set worst single sample: 11 µg/L	126/127	SYR4	2012–2019
Dibromochloromethane	6.775 µg/L No EPA limit set worst single sample: 8.6 µg/L	126/127	SYR4	2012–2019
Chloroform	15.8 µg/L No EPA limit set worst single sample: 24 µg/L	125/127	SYR4	2012–2019
Dichloroacetic Acid	5.35 µg/L No EPA limit set worst single sample: 9.3 µg/L	116/127	SYR4	2012–2019
Total Haloacetic Acids (HAA5)	9.85 µg/L 16% of the EPA limit 60 µg/L worst single sample: 14 µg/L	111/127	SYR4	2012–2019
Dibromoacetic Acid	2.5 µg/L No EPA limit set worst single sample: 2.6 µg/L	96/127	SYR4	2012–2019
Trichloroacetic Acid	3.77 µg/L No EPA limit set worst single sample: 5.4 µg/L	62/127	SYR4	2012–2019
Bromoform	2.005 µg/L No EPA limit set worst single sample: 2.5 µg/L	54/127	SYR4	2012–2019
Nitrate	3390 µg/L 34% of the EPA limit 10000 µg/L worst single sample: 3700 µg/L	50/84	SYR4	2012–2019
Lead	0.0 mg/L 0% of the EPA limit 0.0150 mg/L	41/41	LCR	2023
Arsenic	14 µg/L 140% of the EPA limit, at the 95th percentile of samples — 10 µg/L	29/33	SYR4	2014–2019
Lithium	36 µg/L No EPA limit set	13/13	UCMR-5	2025
Copper	537 µg/L 41% of the EPA limit 1300 µg/L worst single sample: 570 µg/L	3/12	SYR4	2014–2018
Fluoride	400 µg/L 10% of the EPA limit 4000 µg/L	2/2	SYR4	2018
Nitrate-Nitrite	2873 µg/L 29% of the EPA limit 10000 µg/L worst single sample: 3000 µg/L	2/7	SYR4	2017–2018
Methoxychlor	110 µg/L 275% of the EPA limit, at the 95th percentile of samples — 40 µg/L	1/11	SYR4	2014–2018
Monochloroacetic Acid	2.9 µg/L No EPA limit set	1/127	SYR4	2012–2019
Toluene	3.5 µg/L 0.4% of the EPA limit 1000 µg/L	1/7	SYR4	2017–2018

84 contaminants tested, none detected

1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-Dichloropropane11Cl-PF3OUdS2,3,7,8-TCDD2,4,5-TP2,4-D4:2 Fts6:2 Fts8:2 Fts9Cl-PF3ONSAdonaAntimony, TotalAsbestosAtrazineBhc-GammaBariumBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMonobromoacetic AcidNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPfdaPfdoaPfeesaPfhpaPfhpsPfmbaPfmpaPFNAPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: HUDSON, AMANDA
Phone: 707-996-1037
Email: [email protected]

Frequently asked questions about Valley of the Moon Water District

Is Valley of the Moon Water District tap water safe to drink?

EPA monitoring detected 25 contaminants in Valley of the Moon Water District'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 Valley of the Moon Water District's water?

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

How many people does Valley of the Moon Water District serve?

Valley of the Moon Water District reports serving 23,107 people in California, per its EPA record.

Has Valley of the Moon Water District had any water quality violations?

The EPA has 6 violations on file for Valley of the Moon Water District, 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.