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Tap water quality report

Hess Winery

EPA monitoring tested this supplier for 63 contaminants and detected 12. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

63
contaminants tested
12
detected
250
people served
1
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Private
Counties served
Napa

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.

1
health-based violations
12
violations on file
3
still open
ViolationTypeStatusPeriod
TT Health-based Unaddressed 2024-10-17
MR Monitoring Addressed 2025-07-01
RPT Monitoring Unaddressed 2024-10-17
MON Monitoring Resolved 2016-05-01 → 2016-05-31
MON Monitoring Resolved 2016-05-01 → 2016-05-31
MR Monitoring Resolved 2009-05-01 → 2009-05-31
MR Monitoring Resolved 2009-05-01 → 2009-05-31
MR Monitoring Resolved 2006-01-01 → 2006-01-31
MR Monitoring Resolved 2006-01-01 → 2006-01-31
MR Monitoring Archived 2002-12-01 → 2002-12-31

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 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.
ContaminantLevel vs EPA limitDetection rateSourcePeriod
Nitrate
1197.8 µg/L 12%
of the EPA limit 10000 µg/L
 44/48 SYR4 2012–2019
Lead
0.0070 mg/L 47%
of the EPA limit 0.0150 mg/L
 10/10 LCR 2026
Barium
118.6 µg/L 5.9%
of the EPA limit 2000 µg/L
worst single sample: 120 µg/L
5/10 SYR4 2012–2019
Arsenic
2.49 µg/L 25%
of the EPA limit 10 µg/L
worst single sample: 2.5 µg/L
3/10 SYR4 2012–2019
Bromodichloromethane
1.7 µg/L
No EPA limit set
 2/2 SYR4 2016–2019
Chloroform
1.681 µg/L
No EPA limit set
worst single sample: 1.7 µg/L
2/2 SYR4 2016–2019
Dibromochloromethane
1.547 µg/L
No EPA limit set
worst single sample: 1.56 µg/L
2/2 SYR4 2016–2019
TTHM
4.694 µg/L 5.9%
of the EPA limit 80 µg/L
worst single sample: 4.7 µg/L
2/2 SYR4 2016–2019
Dibromoacetic Acid
1.1 µg/L
No EPA limit set
 1/1 SYR4 2019
Dichloroacetic Acid
1.7 µg/L
No EPA limit set
 1/1 SYR4 2019
Total Haloacetic Acids (HAA5)
4.7 µg/L 7.8%
of the EPA limit 60 µg/L
 1/1 SYR4 2019
Trichloroacetic Acid
1.9 µg/L
No EPA limit set
 1/1 SYR4 2019
51 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-Dichloroethane1,2-Dichloropropane2,4,5-TP2,4-DAntimony, TotalAtrazineBhc-GammaBenzeneBeryllium, TotalChlorobenzeneCopperCadmiumCarbofuranCarbon TetrachlorideChromiumDichloromethaneDalaponDinosebDiquatEthylene DibromideEndothallEthylbenzeneFluorideHeptachlorHeptachlor EpoxideLassoLeadMercuryMethoxychlorNitriteOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
SCHNEIDER, ADAM
Phone
707-320-9155
Email
aschneider5@hesspersson.com

Frequently asked questions about Hess Winery

Is Hess Winery tap water safe to drink?

EPA monitoring detected 12 contaminants in Hess Winery'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 Hess Winery's water?

EPA monitoring detected Nitrate, Lead, Barium, Arsenic, Bromodichloromethane, and others. The full list with the level and data source for each is above.

How many people does Hess Winery serve?

Hess Winery reports serving 250 people in California, per its EPA record.

Has Hess Winery had any water quality violations?

The EPA has 12 violations on file for Hess Winery, of which 1 is health-based (a contaminant limit or required treatment was breached) and 3 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.