Is Marin Municipal Water District Tap Water Safe? Quality Report

Water source: Surface water
Ownership: Local government
Counties served: Marin

Compliance record

No violations on file. The EPA has no formal drinking-water violations recorded for this supplier.

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.

Contaminant	Level vs EPA limit	Detection rate	Source	Period
Bromodichloromethane	16.2 µg/L No EPA limit set	327/327	SYR4	2012–2019
Chloroform	68.4 µg/L No EPA limit set	327/327	SYR4	2012–2019
Dibromochloromethane	10.8 µg/L No EPA limit set	326/327	SYR4	2012–2019
TTHM	86.2 µg/L 108% of the EPA limit, in the worst sample — 80 µg/L	324/324	SYR4	2012–2019
Dichloroacetic Acid	57.4 µg/L No EPA limit set	310/315	SYR4	2012–2019
Total Haloacetic Acids (HAA5)	99.2 µg/L 165% of the EPA limit, in the worst sample — 60 µg/L	310/315	SYR4	2012–2019
Trichloroacetic Acid	40.6 µg/L No EPA limit set	278/315	SYR4	2012–2019
Fluoride	1020 µg/L 26% of the EPA limit 4000 µg/L	173/384	SYR4	2012–2019
Dibromoacetic Acid	6.4 µg/L No EPA limit set	107/315	SYR4	2012–2019
Copper	121 µg/L 9.3% of the EPA limit 1300 µg/L	97/388	SYR4	2012–2019
Nitrate-Nitrite	700000 µg/L 7000% of the EPA limit, in the worst sample — 10000 µg/L	85/384	SYR4	2012–2019
Bromoform	2.9 µg/L No EPA limit set	52/327	SYR4	2012–2019
Barium	100 µg/L 5% of the EPA limit 2000 µg/L	39/80	SYR4	2012–2019
Lead	0.0 mg/L 0% of the EPA limit 0.0150 mg/L	32/32	LCR	2021
Nitrate	700.6 µg/L 7% of the EPA limit 10000 µg/L	32/762	SYR4	2012–2019
Monochloroacetic Acid	3.7 µg/L No EPA limit set	31/315	SYR4	2012–2019
Chromium	10 µg/L 10% of the EPA limit 100 µg/L	14/80	SYR4	2012–2019
Nitrite	400 µg/L 40% of the EPA limit 1000 µg/L	4/372	SYR4	2012–2019

91 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, TotalArsenicAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorMonobromoacetic AcidNetfosaaNfdhaNmefosaaOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneLithiumO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact: SELLIER, PAUL
Phone: 415-945-1557
Email: psellier@marinwater.org

Frequently asked questions about Marin Municipal Water District

Is Marin Municipal Water District tap water safe to drink?

EPA monitoring detected 18 contaminants in Marin Municipal 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 Marin Municipal Water District's water?

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

How many people does Marin Municipal Water District serve?

Marin Municipal Water District reports serving 186,895 people in California, per its EPA record.

Has Marin Municipal Water District had any water quality violations?

The EPA has no formal drinking-water violations on file for Marin Municipal Water District.

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.