California Water Service - San Mateo Water System

MyTapWater.org's tap water quality report is the compilation of data collected from federal, state, and local government agencies, most prominently the EPA. We strive to populate the report with the latest data concerning water contaminants, lead and copper levels, and water quality violations. We only collect drinking water data from public water systems.

PWS Service Information
PWS ID: CA4110008
Type: Community water system
EPA Region: 09
Primary Service Area: Residential Area
Primary Source: Surface water purchased
Population Served: 101,004 		Contact Information
JAMES, SOPHIE
JAMES, SOPHIE
1720 NORTH FIRST STREET
SAN JOSE, CA 95112-4508
[email protected]

This public water system services 1 county.

Summary Results

A summary view of tests in which a water contaminant found to exceed the Maximum Contaminant Level (MCL) set by the EPA.

Maximum Contaminant Levels Exceeded (by year):

2013   (0) 2014   (1) 2015   (0) 2016   (0) 2017   (0) 2018   (3)
chlorate anatoxin-a
cylindrospermopsin
total microcystin

Contaminant Detailed Results

This a view of violations of maximum contaminant levels. Use the expanded view see result data for a drinking water contaminant, the minimum level that can be recognized in a test (MRL), and upper limit that is considered healthy (HRL).

chlorate

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2014 2014-10-15 20 210 280
2014 2014-10-15 20 210 320
2014 2014-07-09 20 210 140
2014 2014-07-08 20 210 140
2014 2014-04-01 20 210 65
2014 2014-04-01 20 210 66
2014 2014-01-06 20 210 97
2014 2014-01-06 20 210 99

anatoxin-a

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-07-17 0.03 0.00 < 0.03
2018 2018-07-02 0.03 0.00 < 0.03

cylindrospermopsin

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-07-17 0.09 0.00 < 0.09
2018 2018-07-02 0.09 0.00 < 0.09

total microcystin

Year Test Date MRLMinimum Reporting Level HRLHealth Risk Limit Test Result
2018 2018-07-17 0.3 0.00 < 0.3
2018 2018-07-02 0.3 0.00 < 0.3

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Other Water Contaminants Tested

The following contaminants were tested and found to be within national EPA guidelines.

Contaminant MRLMinimum Reporting Level HRLHealth Risk Limit Avg Result
1,1-dichloroethane 0.03 6.14 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.03 6.14 < 0.03
2014 2014-07-09 0.03 6.14 < 0.03
2014 2014-04-01 0.03 6.14 < 0.03
2014 2014-01-06 0.03 6.14 < 0.03
[+] Expand Test Data
1,2,3-trichloropropane 0.03 0.0004 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.03 0.0004 < 0.03
2014 2014-07-09 0.03 0.0004 < 0.03
2014 2014-04-01 0.03 0.0004 < 0.03
2014 2014-01-06 0.03 0.0004 < 0.03
[+] Expand Test Data
1,3-butadiene 0.1 0.0103 < 0.1 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.1 0.0103 < 0.1
2014 2014-07-09 0.1 0.0103 < 0.1
2014 2014-04-01 0.1 0.0103 < 0.1
2014 2014-01-06 0.1 0.0103 < 0.1
[+] Expand Test Data
1,4-dioxane 0.07 0.35 < 0.07 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.07 0.35 < 0.07
2014 2014-07-09 0.07 0.35 < 0.07
2014 2014-04-01 0.07 0.35 < 0.07
2014 2014-01-06 0.07 0.35 < 0.07
[+] Expand Test Data
bromomethane 0.2 140 < 0.2 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.2 140 < 0.2
2014 2014-07-09 0.2 140 < 0.2
2014 2014-04-01 0.2 140 < 0.2
2014 2014-01-06 0.2 140 < 0.2
[+] Expand Test Data
chloromethane 0.2 2.69 < 0.2 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.2 2.69 < 0.2
2014 2014-07-09 0.2 2.69 < 0.2
2014 2014-04-01 0.2 2.69 < 0.2
2014 2014-01-06 0.2 2.69 < 0.2
[+] Expand Test Data
chromium 0.2 100 0.1375 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2015 2015-06-04 0.2 100 1.1
2015 2015-04-20 0.2 100 < 0.2
2014 2014-10-15 0.2 100 < 0.2
2014 2014-07-09 0.2 100 < 0.2
2014 2014-04-01 0.2 100 < 0.2
2014 2014-04-01 0.2 100 < 0.2
2014 2014-01-06 0.2 100 < 0.2
2014 2014-01-06 0.2 100 < 0.2
[+] Expand Test Data
chromium-6 0.03 0 0.044 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.03 0 0.035
2014 2014-10-15 0.03 0 0.045
2014 2014-07-09 0.03 0 0.032
2014 2014-07-08 0.03 0 0.03
2014 2014-04-01 0.03 0 0.033
2014 2014-04-01 0.03 0 0.03
2014 2014-01-06 0.03 0 0.076
2014 2014-01-06 0.03 0 0.071
[+] Expand Test Data
cobalt 1 70 < 1 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2015 2015-06-04 1 70 < 1
2015 2015-04-20 1 70 < 1
2014 2014-10-15 1 70 < 1
2014 2014-07-09 1 70 < 1
2014 2014-04-01 1 70 < 1
2014 2014-04-01 1 70 < 1
2014 2014-01-06 1 70 < 1
2014 2014-01-06 1 70 < 1
[+] Expand Test Data
Halon 1011 0.06 90 < 0.06 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.06 90 < 0.06
2014 2014-07-09 0.06 90 < 0.06
2014 2014-04-01 0.06 90 < 0.06
2014 2014-01-06 0.06 90 < 0.06
[+] Expand Test Data
HCFC-22 0.08 0 < 0.08 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.08 0 < 0.08
2014 2014-07-09 0.08 0 < 0.08
2014 2014-04-01 0.08 0 < 0.08
2014 2014-01-06 0.08 0 < 0.08
[+] Expand Test Data
molybdenum 1 40 0.1625 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2015 2015-06-04 1 40 1.3
2015 2015-04-20 1 40 < 1
2014 2014-10-15 1 40 < 1
2014 2014-07-09 1 40 < 1
2014 2014-04-01 1 40 < 1
2014 2014-04-01 1 40 < 1
2014 2014-01-06 1 40 < 1
2014 2014-01-06 1 40 < 1
[+] Expand Test Data
PFBS 0.09 0 < 0.09 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.09 0 < 0.09
2014 2014-07-09 0.09 0 < 0.09
2014 2014-04-01 0.09 0 < 0.09
2014 2014-01-06 0.09 0 < 0.09
[+] Expand Test Data
PFHpA 0.01 0 < 0.01 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.01 0 < 0.01
2014 2014-07-09 0.01 0 < 0.01
2014 2014-04-01 0.01 0 < 0.01
2014 2014-01-06 0.01 0 < 0.01
[+] Expand Test Data
PFHxS 0.03 0 < 0.03 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.03 0 < 0.03
2014 2014-07-09 0.03 0 < 0.03
2014 2014-04-01 0.03 0 < 0.03
2014 2014-01-06 0.03 0 < 0.03
[+] Expand Test Data
PFNA 0.02 0 < 0.02 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.02 0 < 0.02
2014 2014-07-09 0.02 0 < 0.02
2014 2014-04-01 0.02 0 < 0.02
2014 2014-01-06 0.02 0 < 0.02
[+] Expand Test Data
PFOA 0.02 0.07 < 0.02 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.02 0.07 < 0.02
2014 2014-07-09 0.02 0.07 < 0.02
2014 2014-04-01 0.02 0.07 < 0.02
2014 2014-01-06 0.02 0.07 < 0.02
[+] Expand Test Data
PFOS 0.04 0.07 < 0.04 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2014 2014-10-15 0.04 0.07 < 0.04
2014 2014-07-09 0.04 0.07 < 0.04
2014 2014-04-01 0.04 0.07 < 0.04
2014 2014-01-06 0.04 0.07 < 0.04
[+] Expand Test Data
strontium 0.3 1500 137.125 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2015 2015-06-04 0.3 1500 890
2015 2015-04-20 0.3 1500 19
2014 2014-10-15 0.3 1500 46
2014 2014-07-09 0.3 1500 14
2014 2014-04-01 0.3 1500 15
2014 2014-04-01 0.3 1500 17
2014 2014-01-06 0.3 1500 47
2014 2014-01-06 0.3 1500 49
[+] Expand Test Data
vanadium 0.2 21 0.8438 [+] Expand Test Data
Year Test Date MRL HRL Test Result
2015 2015-06-04 0.2 21 6.1
2015 2015-04-20 0.2 21 < 0.2
2014 2014-10-15 0.2 21 0.21
2014 2014-07-09 0.2 21 < 0.2
2014 2014-04-01 0.2 21 < 0.2
2014 2014-04-01 0.2 21 < 0.2
2014 2014-01-06 0.2 21 0.23
2014 2014-01-06 0.2 21 0.21
[+] Expand Test Data

Lead and Copper Data

Lead and copper are recorded separately from other contaminants because of the Lead and Copper Rule. As with all other results, these are the findings at the water supply level. Lead and copper can be — and often are — deposited in drinking water in between the water facility and your tap.

Sample ID Contaminant Sampling Start Date Sampling End Date Result
CA65172 lead 2017-01-01 2019-12-31 0.00594mg/L
CA53861 lead 2016-01-01 2018-12-31 0mg/L
CA38914 lead 2013-01-01 2015-12-31 0.0088mg/L

Violations

Known violations of the Safe Drinking Water Act as recorded by the EPA.

Compliance Dates Rule Violation Type Contaminant Name Status
- N/A Total Coliform Rule Maximum Contaminant Level Violation, Monthly (TCR) Coliform (TCR) Known
- N/A Surface Water Treatment Rule Treatment Technique (SWTR and GWR) Surface Water Treatment Rule Returned to Compliance

Local Water Testing

Find a lab in your area so you can get your tap or well water tested. This list contains both governmental and private labs, all of which are EPA-certified for drinking water testing.

Lab Location Zip Code
Torrent Laboratory, Inc. Milpitas, CA 95035
Datalab San Jose, CA 95131
Santa Clara County Public Health Lab San Jose, CA 95128

Water Bill Information

Convenient information about your water service.

Unable to identify any billing information about California Water Service - San Mateo (CA4110008).

What My Water Data Means

Water data isn't always easy to interpret, but by following the links on this page you should be able to have most of your questions answered. By clicking the name of a water contaminant or secondary substance you can learn about that specific substance. Ultimately this page should give you some insight towards learning if your water is safe, what water filter you should buy (if any), and how well your local water compares against other sources.

Sources

The origin of MyTapWater.org's water data is explained on our Data Sources page.

Why Is My Water Data Not More Recent?

The recency of the data for your ZIP code depends on the last your water source was tested, by a federal, state, or local agency. More information about the timing can be determined by learning about the dataset in question and seeing how often the EPA (other another governing body) mandated testing.