← California

Tap water quality report

Napa River Ranch

EPA monitoring tested this supplier for 67 contaminants and detected 15. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

67
contaminants tested
15
detected
70
people served
3
health-based violations
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.

3
health-based violations
69
violations on file
20
still open
ViolationTypeStatusPeriod
TT Health-based Unaddressed 2024-10-17
TT Health-based Resolved 2022-12-01
TT Health-based Resolved 2022-12-01
MR Monitoring Addressed 2026-01-01
MR Monitoring Addressed 2026-01-01
MR Monitoring Addressed 2026-01-01
MR Monitoring Addressed 2025-07-01
MR Monitoring Addressed 2025-07-01
MR Monitoring Addressed 2025-07-01
MR Monitoring Addressed 2025-07-01

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
Lead
0.0044 mg/L 29%
of the EPA limit 0.0150 mg/L
12/12 LCR 2024
Nitrate
1333.4 µg/L 13%
of the EPA limit 10000 µg/L
6/6 SYR4 2015–2019
Arsenic
6.6 µg/L 66%
of the EPA limit 10 µg/L
2/2 SYR4 2015–2019
Barium
4900 µg/L 245%
of the EPA limit, in the worst sample — 2000 µg/L
2/2 SYR4 2015–2019
Bromodichloromethane
0.7300 µg/L
No EPA limit set
1/1 SYR4 2012
Bromoform
2.5 µg/L
No EPA limit set
1/1 SYR4 2012
Chloroform
0.7000 µg/L
No EPA limit set
1/1 SYR4 2012
Dibromoacetic Acid
12.6 µg/L
No EPA limit set
1/1 SYR4 2012
Dibromochloromethane
1 µg/L
No EPA limit set
1/1 SYR4 2012
Dichloroacetic Acid
1.48 µg/L
No EPA limit set
1/1 SYR4 2012
Fluoride
170 µg/L 4.3%
of the EPA limit 4000 µg/L
1/2 SYR4 2015–2019
Monobromoacetic Acid
2.34 µg/L
No EPA limit set
1/1 SYR4 2012
TTHM
4.9 µg/L 6.1%
of the EPA limit 80 µg/L
1/1 SYR4 2012
Thallium, Total
1 µg/L 50%
of the EPA limit 2 µg/L
1/2 SYR4 2015–2019
Total Haloacetic Acids (HAA5)
16.4 µg/L 27%
of the EPA limit 60 µg/L
1/1 SYR4 2012
52 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 TetrachlorideChlordaneChromiumDichloromethaneDalaponDinosebDiquatEthylene DibromideEndothallEndrinEthylbenzeneHexachlorobenzeneHeptachlorHeptachlor EpoxideHexachlorocyclopentadieneLassoMercuryMethoxychlorNitriteOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneTolueneToxapheneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
GIOVANNONI, DAN
Phone
707-333-6596
Email
dpgiovannoni@gmail.com

Frequently asked questions about Napa River Ranch

Is Napa River Ranch tap water safe to drink?

EPA monitoring detected 15 contaminants in Napa River Ranch'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 Napa River Ranch's water?

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

How many people does Napa River Ranch serve?

Napa River Ranch reports serving 70 people in California, per its EPA record.

Has Napa River Ranch had any water quality violations?

The EPA has 69 violations on file for Napa River Ranch, of which 3 are health-based (a contaminant limit or required treatment was breached) and 20 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.