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Tap water quality report

Hollister, City of

EPA monitoring tested this supplier for 111 contaminants and detected 21. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

111
contaminants tested
21
detected
26,017
people served
12
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
SWP
Ownership
Local government
Counties served
San Benito

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.

12
health-based violations
33
violations on file
0
still open
ViolationTypeStatusPeriod
MCL Health-based Resolved 2022-07-01 → 2022-09-30
MCL Health-based Resolved 2022-07-01 → 2022-09-30
MCL Health-based Resolved 2018-10-01 → 2018-12-31
MCL Health-based Resolved 2018-10-01 → 2018-12-31
MCL Health-based Resolved 2018-07-01 → 2018-09-30
MCL Health-based Resolved 2018-07-01 → 2018-09-30
MCL Health-based Resolved 2016-01-01 → 2016-03-31
MCL Health-based Resolved 2016-01-01 → 2016-03-31
MCL Health-based Resolved 2015-10-01 → 2015-12-31
MCL Health-based Resolved 2015-10-01 → 2015-12-31

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
Nitrate
9040 µg/L 90%
of the EPA limit 10000 µg/L
 282/284 SYR4 2012–2019
Bromoform
105.05 µg/L
No EPA limit set
 123/125 SYR4 2013–2019
Dibromochloromethane
77.57 µg/L
No EPA limit set
 123/125 SYR4 2013–2019
TTHM
158.96 µg/L 199%
of the EPA limit, in the worst sample — 80 µg/L
 123/125 SYR4 2013–2019
Dibromoacetic Acid
18.2 µg/L
No EPA limit set
 116/122 SYR4 2013–2019
Total Haloacetic Acids (HAA5)
28.1 µg/L 47%
of the EPA limit 60 µg/L
 115/122 SYR4 2013–2019
Bromodichloromethane
22.46 µg/L
No EPA limit set
 101/125 SYR4 2013–2019
Lead
0.0023 mg/L 15%
of the EPA limit 0.0150 mg/L
 47/47 LCR 2023
Monobromoacetic Acid
3 µg/L
No EPA limit set
 42/122 SYR4 2013–2019
Dichloroacetic Acid
3.6 µg/L
No EPA limit set
 39/122 SYR4 2013–2019
Chloroform
6.98 µg/L
No EPA limit set
 29/125 SYR4 2013–2019
Lithium
29 µg/L
No EPA limit set
 13/22 UCMR-5 2024
Fluoride
380 µg/L 9.5%
of the EPA limit 4000 µg/L
 11/11 SYR4 2014–2017
Trichloroacetic Acid
7.1 µg/L
No EPA limit set
 10/122 SYR4 2013–2019
Chromium
33 µg/L 33%
of the EPA limit 100 µg/L
 6/11 SYR4 2014–2017
Nitrate-Nitrite
4900 µg/L 49%
of the EPA limit 10000 µg/L
 4/4 SYR4 2019
Selenium
6.7 µg/L 13%
of the EPA limit 50 µg/L
 3/11 SYR4 2014–2017
Arsenic
4.3 µg/L 43%
of the EPA limit 10 µg/L
 2/11 SYR4 2014–2017
Copper
97 µg/L 7.5%
of the EPA limit 1300 µg/L
 2/16 SYR4 2014–2017
Combined Uranium
8.4334 µg/L 28%
of the EPA limit 30 µg/L
 1/1 SYR4 2017
Lead
11 µg/L 73%
of the EPA limit 15 µg/L
 1/6 SYR4 2014
90 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, TotalChlorobenzeneCyanideCadmiumCarbofuranCarbon TetrachlorideChlordaneDichloromethaneDalaponDi(2-ethylhexyl) AdipateDi(2-ethylhexyl) PhthalateDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneGlyphosateHexachlorobenzeneHfpo-DaHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorMonochloroacetic AcidNetfosaaNfdhaNmefosaaNitriteOxamylPfbaPFBSPfdaPfdoaPfeesaPfhpaPfhpsPfhxaPFHXSPfmbaPfmpaPFNAPFOAPFOSPfpeaPfpesPftaPftrdaPfunaPentachlorophenolPicloramSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTotal Polychlorinated Biphenyls (PCB)ToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
HERNANDEZ, JAVIER
Phone
831-636-4370
Email
Javier.Hernandez@hollister.ca.gov

Frequently asked questions about Hollister, City of

Is Hollister, City of tap water safe to drink?

EPA monitoring detected 21 contaminants in Hollister, City 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 Hollister, City of's water?

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

How many people does Hollister, City of serve?

Hollister, City of reports serving 26,017 people in California, per its EPA record.

Has Hollister, City of had any water quality violations?

The EPA has 33 violations on file for Hollister, City of, of which 12 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.