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PublicWater Watch

City of Modesto

Published drinking-water records and contacts for City of Modesto. System CA5010010. Review sources and dates; not a real-time water assessment.

System ID
CA5010010
State or territory
CA
Published population served
218771
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.

Read the provider’s annual water quality report

Report link listed: 2026-10-05. This is not the report’s sampling date.

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/L2024-09-12Well 16 / 5010010914
4:2 FTS< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
6:2 FTS< 0.005 µg/L0.005 µg/L2024-09-12Well 16 / 5010010914
8:2 FTS< 0.005 µg/L0.005 µg/L2024-09-12Well 16 / 5010010914
9Cl-PF3ONS< 0.002 µg/L0.002 µg/L2024-09-12Well 16 / 5010010914
ADONA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
HFPO-DA< 0.005 µg/L0.005 µg/L2024-09-12Well 16 / 5010010914
NEtFOSAA< 0.005 µg/L0.005 µg/L2024-08-14Well 300 / 5010010920
NFDHA< 0.02 µg/L0.02 µg/L2024-09-12Well 16 / 5010010914
NMeFOSAA< 0.006 µg/L0.006 µg/L2024-08-14Surface Water TP / 5010010941
PFBA< 0.005 µg/L0.005 µg/L2024-09-12Well 16 / 5010010914
PFBS0.0034 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFDA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFDoA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFEESA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFHpA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFHpS< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFHxA0.0039 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFHxS0.0069 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFMBA< 0.003 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFMPA< 0.004 µg/L0.004 µg/L2024-09-12Well 16 / 5010010914
PFNA< 0.004 µg/L0.004 µg/L2024-09-12Well 16 / 5010010914
PFOA0.0041 µg/L0.004 µg/L2024-09-12Well 16 / 5010010914
PFOS0.0046 µg/L0.004 µg/L2024-09-12Well 16 / 5010010914
PFPeA0.0046 µg/L0.003 µg/L2024-09-12Well 16 / 5010010914
PFPeS< 0.004 µg/L0.004 µg/L2024-09-12Well 16 / 5010010914
PFTA< 0.008 µg/L0.008 µg/L2024-08-14Surface Water TP / 5010010941
PFTrDA< 0.007 µg/L0.007 µg/L2024-08-14Surface Water TP / 5010010941
PFUnA< 0.002 µg/L0.002 µg/L2024-09-12Well 16 / 5010010914
lithium< 9 µg/L9 µg/L2024-08-14Surface Water TP / 5010010941

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) 0.012 mg/L2025-01-01 – 2027-12-312026Q3
Lead (PB90) 0 mg/L2022-01-01 – 2024-12-312026Q3
Lead (PB90) 0 mg/L2021-01-01 – 2023-12-312026Q3
Lead (PB90) 0 mg/L2019-01-01 – 2021-12-312026Q3
Lead (PB90) 0 mg/L2016-01-01 – 2018-12-312026Q3
Lead (PB90) 0 mg/L2013-01-01 – 2015-12-312026Q3
Lead (PB90) 0 mg/L2010-01-01 – 2012-12-312026Q3
Lead (PB90) 0.0025 mg/L2007-01-01 – 2009-12-312026Q3
Twelve most recent imported state laboratory records
SubstancePublished resultSample dateLocation / source
NITRATE3.4 MG/L2026-06-24WELL 214 / California DDW laboratory results
NITRATE9.1 MG/L2026-06-24WELL 049 - RAW PRE-BLEND / California DDW laboratory results
ARSENIC4.9 UG/L2026-06-24WELL 066 / California DDW laboratory results
NITRATE6.8 MG/L2026-06-24WELL 212 - TREATED - GAC / California DDW laboratory results
NITRATE6.0 MG/L2026-06-24WELL 292 - TREATED - GAC / California DDW laboratory results
ARSENIC< 2.000000000 UG/L2026-06-24TANK NO. 06 - BLEND 301,304,MID / California DDW laboratory results
NITRATE4.3 MG/L2026-06-24WELL 049 - TREATED - BLEND DIST / California DDW laboratory results
NITRATE3.1 MG/L2026-06-24TANK NO. 08 - BLEND 223,305,DIST / California DDW laboratory results
NITRATE5.6 MG/L2026-06-24WELL 279 - TREATED - GAC / California DDW laboratory results
NITRATE6.5 MG/L2026-06-24WELL 247 / California DDW laboratory results
COMBINED URANIUM< 1.000000000 PCI/L2026-06-24WELL 283 - TREATED - BLEND MID / California DDW laboratory results
ARSENIC< 2.000000000 UG/L2026-06-24TANK NO. 10 / 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

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

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)

Martinez, Manuel: 209-342-4592

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