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Tap water quality report

City of Mountain View

EPA monitoring tested this supplier for 113 contaminants and detected 20. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

113
contaminants tested
20
detected
81,501
people served
10
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
SWP
Ownership
Local government
Counties served
Santa Clara

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.

10
health-based violations
17
violations on file
0
still open
ViolationTypeStatusPeriod
TT Health-based Resolved 2015-03-01 → 2015-03-31
TT Health-based Resolved 2015-03-01 → 2015-03-31
TT Health-based Resolved 1995-03-01 → 1995-03-31
TT Health-based Resolved 1995-03-01 → 1995-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31
TT Health-based Resolved 1992-03-01 → 1992-03-31

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
78.82 µg/L
No EPA limit set
 252/252 SYR4 2012–2019
TTHM
102.21 µg/L 128%
of the EPA limit, in the worst sample — 80 µg/L
 252/252 SYR4 2012–2019
Total Haloacetic Acids (HAA5)
70.7 µg/L 118%
of the EPA limit, in the worst sample — 60 µg/L
 252/252 SYR4 2012–2019
Dichloroacetic Acid
41.9 µg/L
No EPA limit set
 251/252 SYR4 2012–2019
Trichloroacetic Acid
34.2 µg/L
No EPA limit set
 232/252 SYR4 2012–2019
Bromodichloromethane
31.8 µg/L
No EPA limit set
 223/252 SYR4 2012–2019
Nitrate
7232 µg/L 72%
of the EPA limit 10000 µg/L
 196/198 SYR4 2012–2019
Dibromochloromethane
36.87 µg/L
No EPA limit set
 105/252 SYR4 2012–2019
Bromoform
26.34 µg/L
No EPA limit set
 92/252 SYR4 2012–2019
Dibromoacetic Acid
17.7 µg/L
No EPA limit set
 87/252 SYR4 2012–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 35/35 LCR 2025
Fluoride
760 µg/L 19%
of the EPA limit 4000 µg/L
 25/28 SYR4 2012–2019
Monobromoacetic Acid
4.2 µg/L
No EPA limit set
 19/252 SYR4 2012–2019
Monochloroacetic Acid
3.8 µg/L
No EPA limit set
 14/252 SYR4 2012–2019
Barium
150 µg/L 7.5%
of the EPA limit 2000 µg/L
 9/9 SYR4 2013–2018
Nitrate-Nitrite
6300 µg/L 63%
of the EPA limit 10000 µg/L
 5/5 SYR4 2016–2018
Combined Radium (-226 And -228)
1.01 pCi/L 20%
of the EPA limit 5 pCi/L
 1/1 SYR4 2013
Diquat
2.4 µg/L 12%
of the EPA limit 20 µg/L
 1/18 SYR4 2013–2019
Gross Beta Particle Activity
2.3 pCi/L
No EPA limit set
 1/1 SYR4 2013
Lithium
9.3 µg/L
No EPA limit set
 1/16 UCMR-5 2023
93 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, TotalArsenicAsbestosAtrazineBhc-GammaBenzeneBenzo(A)PyreneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneChromiumCombined UraniumDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoLeadMercuryMethoxychlorNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
AU, LISA
Phone
650-903-6140
Email
Lisa.Au@mountainview.gov

Frequently asked questions about City of Mountain View

Is City of Mountain View tap water safe to drink?

EPA monitoring detected 20 contaminants in City of Mountain View'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 City of Mountain View's water?

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

How many people does City of Mountain View serve?

City of Mountain View reports serving 81,501 people in California, per its EPA record.

Has City of Mountain View had any water quality violations?

The EPA has 17 violations on file for City of Mountain View, of which 10 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.