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Tap water quality report

Rancho San Joaquin Water Sys

EPA monitoring tested this supplier for 45 contaminants and detected 10. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

45
contaminants tested
10
detected
172
people served
0
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Local government
Counties served
San Joaquin

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.

0
health-based violations
2
violations on file
0
still open
ViolationTypeStatusPeriod
MR Monitoring Archived 1981-10-01 → 1982-09-30
MR Monitoring Archived 1980-10-30 → 1981-10-29

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
5300 µg/L 53%
of the EPA limit 10000 µg/L
 18/34 SYR4 2012–2019
Combined Uranium
32.333 µg/L 108%
of the EPA limit, in the worst sample — 30 µg/L
 17/17 SYR4 2016–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 7/7 LCR 2024
Arsenic
5 µg/L 50%
of the EPA limit 10 µg/L
 4/4 SYR4 2013–2018
Barium
298 µg/L 15%
of the EPA limit 2000 µg/L
 4/4 SYR4 2013–2018
Chromium
5 µg/L 5%
of the EPA limit 100 µg/L
 2/4 SYR4 2013–2018
Lead
9.4 µg/L 63%
of the EPA limit 15 µg/L
 2/4 SYR4 2013–2018
Copper
90 µg/L 6.9%
of the EPA limit 1300 µg/L
 1/3 SYR4 2014–2018
Nitrate-Nitrite
3700 µg/L 37%
of the EPA limit 10000 µg/L
 1/3 SYR4 2013–2018
Selenium
2 µg/L 4%
of the EPA limit 50 µg/L
 1/4 SYR4 2013–2018
35 contaminants tested, none detected
1,1,1-Trichloroethane1,1,2-Trichloroethane1,1-Dichloroethylene1,2,4-Trichlorobenzene1,2-DIBROMO-3-CHLOROPROPANE1,2-Dichloroethane1,2-DichloropropaneAntimony, TotalBenzeneBeryllium, TotalBromodichloromethaneBromoformChlorobenzeneCadmiumCarbon TetrachlorideChloroformDichloromethaneDibromochloromethaneEthylene DibromideEthylbenzeneFluorideMercuryNitriteStyreneTTHMTetrachloroethyleneThallium, TotalTolueneTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
MAINTENANCE DIST, SJC UTILITIES
Phone
209-468-3090
Email
cirons@sjgov.org

Frequently asked questions about Rancho San Joaquin Water Sys

Is Rancho San Joaquin Water Sys tap water safe to drink?

EPA monitoring detected 10 contaminants in Rancho San Joaquin Water Sys'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 Rancho San Joaquin Water Sys's water?

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

How many people does Rancho San Joaquin Water Sys serve?

Rancho San Joaquin Water Sys reports serving 172 people in California, per its EPA record.

Has Rancho San Joaquin Water Sys had any water quality violations?

The EPA has 2 violations on file for Rancho San Joaquin Water Sys, of which 0 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.