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PublicWater Watch

City of Patterson

Published drinking-water records and contacts for City of Patterson. System CA5010017. Review sources and dates; not a real-time water assessment.

System ID
CA5010017
State or territory
CA
Published population served
24977
System type (source code)
CWS

Published records and dates

Missing records here do not mean the provider did not test. Published records are not a real-time assessment of your tap water.

Published testing results

Selected recent records are shown below. Different sampling locations and dates are not interchangeable. These excerpts are not a complete testing history.

“<” means below the stated reporting limit, not zero. A reported measurement alone is not a safety verdict. Read an example

EPA UCMR 5 — most recent imported sample per substance
SubstancePublished resultReporting limitSample dateSampling location
11Cl-PF3OUdS< 0.005 µg/L0.005 µg/L2024-12-11Well 6 / 5010017801
4:2 FTS< 0.003 µg/L0.003 µg/L2024-12-11Well 8 / 5010017805
6:2 FTS< 0.005 µg/L0.005 µg/L2024-12-11Well 8 / 5010017805
8:2 FTS< 0.005 µg/L0.005 µg/L2024-12-11Well 9 / 5010017809
9Cl-PF3ONS< 0.002 µg/L0.002 µg/L2024-12-11Well 9 / 5010017809
ADONA< 0.003 µg/L0.003 µg/L2024-12-11Well 7 / 5010017806
HFPO-DA< 0.005 µg/L0.005 µg/L2024-12-11Well 6 / 5010017801
NEtFOSAA< 0.005 µg/L0.005 µg/L2024-12-11Well 6 / 5010017801
NFDHA< 0.02 µg/L0.02 µg/L2024-12-11Well 11 / 5010017808
NMeFOSAA< 0.006 µg/L0.006 µg/L2024-12-11Well 11 / 5010017808
PFBA< 0.005 µg/L0.005 µg/L2024-12-11Well 7 / 5010017806
PFBS< 0.003 µg/L0.003 µg/L2024-12-11Well 9 / 5010017809
PFDA< 0.003 µg/L0.003 µg/L2024-12-11Well 6 / 5010017801
PFDoA< 0.003 µg/L0.003 µg/L2024-12-11Well 6 / 5010017801
PFEESA< 0.003 µg/L0.003 µg/L2024-12-11Well 11 / 5010017808
PFHpA< 0.003 µg/L0.003 µg/L2024-12-11Well 8 / 5010017805
PFHpS< 0.003 µg/L0.003 µg/L2024-12-11Well 5 / 5010017803
PFHxA< 0.003 µg/L0.003 µg/L2024-12-11Well 8 / 5010017805
PFHxS< 0.003 µg/L0.003 µg/L2024-12-11Well 9 / 5010017809
PFMBA< 0.003 µg/L0.003 µg/L2024-12-11Well 9 / 5010017809
PFMPA< 0.004 µg/L0.004 µg/L2024-12-11Well 11 / 5010017808
PFNA< 0.004 µg/L0.004 µg/L2024-12-11Well 8 / 5010017805
PFOA< 0.004 µg/L0.004 µg/L2024-12-11Well 8 / 5010017805
PFOS< 0.004 µg/L0.004 µg/L2024-12-11Well 11 / 5010017808
PFPeA< 0.003 µg/L0.003 µg/L2024-12-11Well 6 / 5010017801
PFPeS< 0.004 µg/L0.004 µg/L2024-12-11Well 6 / 5010017801
PFTA< 0.008 µg/L0.008 µg/L2024-12-11Well 7 / 5010017806
PFTrDA< 0.007 µg/L0.007 µg/L2024-12-11Well 11 / 5010017808
PFUnA< 0.002 µg/L0.002 µg/L2024-12-11Well 5 / 5010017803
lithium31 µg/L9 µg/L2024-12-11Well 8 / 5010017805

Download all EPA UCMR 5 records (CSV)

Lead and copper: 90th-percentile summaries

These describe a monitoring period across sampled locations, not the result at your home. How to read the 90th percentile

Eight most recent imported monitoring summaries
SubstancePublished 90th percentileMonitoring periodSource quarter
Lead (PB90) 0 mg/L2022-01-01 – 2024-12-312026Q3
Lead (PB90) 0 mg/L2019-01-01 – 2021-12-312026Q3
Lead (PB90) 0.0017 mg/L2016-01-01 – 2018-12-312026Q3
Lead (PB90) 0 mg/L2013-01-01 – 2015-12-312026Q3
Lead (PB90) 0.0006 mg/L2010-01-01 – 2012-12-312026Q3
Lead (PB90) 0.0018 mg/L2009-01-01 – 2009-12-312026Q3
Lead (PB90) 0.0016 mg/L2006-01-01 – 2006-12-312026Q3
Lead (PB90) 0.0016 mg/L2006-01-01 – 2006-12-312026Q3
Twelve most recent imported state laboratory records
SubstancePublished resultSample dateLocation / source
ISOPROPYLBENZENE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
1,2-DICHLOROPROPANE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
COPPER, FREE< 10.000000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
CIS-1,2-DICHLOROETHYLENE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
CHLOROBENZENE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
TERT-AMYL-METHYL ETHER< 2.000000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
NITRATE-NITRITE2.4 MG/L2026-06-09WELL NO. 09 / California DDW laboratory results
BROMODICHLOROMETHANE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
SELENIUM8 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
SULFATE301 MG/L2026-06-09WELL NO. 09 / California DDW laboratory results
CHLOROFORM< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results
P-CHLOROTOLUENE< 0.500000000 UG/L2026-06-09WELL NO. 09 / California DDW laboratory results

State sampling points can include untreated water. Publisher qualifiers and units are retained; consult the full source notes before interpreting a record.

Download state records with source notes (CSV)

Published compliance history

1 imported records. Status is as recorded in the source; historical records are not current advisories. Missing records do not establish that no violations occurred.

Twenty most recent imported compliance records
Rule / recordPeriodRecorded statusHealth-based (EPA classification)Source quarter
Miscellaneous Other Rules / Notification, Public1989-08-01 – 1989-08-31ArchivedNo2026Q3

Source dates and refresh checks

A refresh check is not a sample date. Publication periods, sample dates and checks are shown separately.

Administrative contact (EPA filing)

Willett, Mike: 209-895-8065

An administrative filing contact may not be a customer-service line. Confirm current contact details with the provider.

Official state resources · How to read these records