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Tap water quality report

Rancho San Joaquin Mwc

EPA monitoring tested this supplier for 62 contaminants and detected 16. A detection doesn't automatically mean the water is unsafe — the level and EPA source for each is below.

62
contaminants tested
16
detected
914
people served
16
health-based violations
California rankingsLead in CaliforniaPFAS in California
Water source
Ground water
Ownership
Private
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.

16
health-based violations
43
violations on file
2
still open
ViolationTypeStatusPeriod
TT Health-based Unaddressed 2024-10-17
MCL Health-based Archived 2023-07-01 → 2024-06-30
MCL Health-based Archived 2022-10-01 → 2023-09-30
MCL Health-based Resolved 1997-08-01 → 1997-08-31
MCL Health-based Resolved 1997-08-01 → 1997-08-31
MCL Health-based Resolved 1997-08-01 → 1997-08-31
MCL Health-based Resolved 1997-08-01 → 1997-08-31
MCL Health-based Resolved 1996-10-01 → 1996-10-31
MCL Health-based Resolved 1996-10-01 → 1996-10-31
MCL Health-based Resolved 1996-10-01 → 1996-10-31

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
5198 µg/L 52%
of the EPA limit 10000 µg/L
worst single sample: 5200 µg/L
54/56 SYR4 2012–2019
Arsenic
10.22 µg/L 102%
of the EPA limit, at the 95th percentile of samples — 10 µg/L
worst single sample: 11 µg/L
13/16 SYR4 2013–2019
Lead
0.0 mg/L 0%
of the EPA limit 0.0150 mg/L
 12/12 LCR 2024
Bromoform
25.004 µg/L
No EPA limit set
worst single sample: 26 µg/L
4/7 SYR4 2015–2018
Dibromoacetic Acid
6.005 µg/L
No EPA limit set
worst single sample: 6.2 µg/L
4/7 SYR4 2015–2018
TTHM
61.6745 µg/L 77%
of the EPA limit 80 µg/L
worst single sample: 68 µg/L
4/7 SYR4 2015–2018
Total Haloacetic Acids (HAA5)
7.025 µg/L 12%
of the EPA limit 60 µg/L
worst single sample: 7.4 µg/L
4/7 SYR4 2015–2018
Barium
248 µg/L 12%
of the EPA limit 2000 µg/L
worst single sample: 250 µg/L
3/3 SYR4 2013–2019
Dibromochloromethane
22.122 µg/L
No EPA limit set
worst single sample: 24 µg/L
3/7 SYR4 2015–2018
Fluoride
381 µg/L 9.5%
of the EPA limit 4000 µg/L
worst single sample: 390 µg/L
3/3 SYR4 2013–2019
Bromodichloromethane
13.3625 µg/L
No EPA limit set
worst single sample: 14 µg/L
2/7 SYR4 2015–2018
Combined Uranium
4.25991 µg/L 14%
of the EPA limit 30 µg/L
worst single sample: 4.321 µg/L
2/2 SYR4 2016
Chloroform
4.4 µg/L
No EPA limit set
 1/7 SYR4 2015–2018
Chromium
8 µg/L 8%
of the EPA limit 100 µg/L
 1/3 SYR4 2013–2019
Dichloroacetic Acid
1.2 µg/L
No EPA limit set
 1/7 SYR4 2015–2018
Nitrite
0.0600 µg/L 0%
of the EPA limit 1000 µg/L
 1/5 SYR4 2013–2019
46 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, TotalAsbestosAtrazineBenzeneBeryllium, TotalChlorobenzeneCopperCyanideCadmiumCarbofuranCarbon TetrachlorideDichloromethaneDalaponDinosebDiquatEthylbenzeneLassoLeadMercuryMonobromoacetic AcidMonochloroacetic AcidOxamylPentachlorophenolPicloramSeleniumSimazineStyreneTetrachloroethyleneThallium, TotalTolueneTrichloroacetic AcidTrichloroethyleneVinyl ChlorideXylenes, Totalcis-1,2-DichloroethyleneO-DichlorobenzeneP-Dichlorobenzenetrans-1,2-Dichloroethylene

Utility contact

Contact
ROCHA, SUSAN
Phone
408-804-1401
Email
[email protected]

Frequently asked questions about Rancho San Joaquin Mwc

Is Rancho San Joaquin Mwc tap water safe to drink?

EPA monitoring detected 16 contaminants in Rancho San Joaquin Mwc'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 Mwc's water?

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

How many people does Rancho San Joaquin Mwc serve?

Rancho San Joaquin Mwc reports serving 914 people in California, per its EPA record.

Has Rancho San Joaquin Mwc had any water quality violations?

The EPA has 43 violations on file for Rancho San Joaquin Mwc, of which 16 are health-based (a contaminant limit or required treatment was breached) and 2 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.