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PublicWater Watch

Gswc-San Dimas

Published drinking-water records and contacts for Gswc-San Dimas. System CA1910142. Review sources and dates; not a real-time water assessment.

System ID
CA1910142
State or territory
CA
Published population served
56538
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/L2025-08-27Highway Treatment Plant / 1910142022
4:2 FTS< 0.003 µg/L0.003 µg/L2025-08-27MWD Intertie / 1910142816
6:2 FTS< 0.005 µg/L0.005 µg/L2025-08-27Highway Treatment Plant / 1910142022
8:2 FTS< 0.005 µg/L0.005 µg/L2025-08-27MWD Intertie / 1910142816
9Cl-PF3ONS< 0.002 µg/L0.002 µg/L2025-08-27Highway Treatment Plant / 1910142022
ADONA< 0.003 µg/L0.003 µg/L2025-08-27Covina Irrigating Company / 1910142817
HFPO-DA< 0.005 µg/L0.005 µg/L2025-08-27Highway Treatment Plant / 1910142022
NEtFOSAA< 0.005 µg/L0.005 µg/L2025-08-27Highway Treatment Plant / 1910142022
NFDHA< 0.02 µg/L0.02 µg/L2025-08-27MWD Intertie / 1910142816
NMeFOSAA< 0.006 µg/L0.006 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFBA0.02 µg/L0.005 µg/L2025-08-27TVMWD / 1910142818
PFBS< 0.003 µg/L0.003 µg/L2025-08-27MWD Intertie / 1910142816
PFDA< 0.003 µg/L0.003 µg/L2025-08-27Covina Irrigating Company / 1910142817
PFDoA< 0.003 µg/L0.003 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFEESA< 0.003 µg/L0.003 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFHpA< 0.003 µg/L0.003 µg/L2025-08-27TVMWD / 1910142818
PFHpS< 0.003 µg/L0.003 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFHxA< 0.003 µg/L0.003 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFHxS< 0.003 µg/L0.003 µg/L2025-08-27MWD Intertie / 1910142816
PFMBA< 0.003 µg/L0.003 µg/L2025-08-27MWD Intertie / 1910142816
PFMPA< 0.004 µg/L0.004 µg/L2025-08-27TVMWD / 1910142818
PFNA< 0.004 µg/L0.004 µg/L2025-08-27Highway Treatment Plant / 1910142022
PFOA< 0.004 µg/L0.004 µg/L2025-08-27MWD Intertie / 1910142816
PFOS< 0.004 µg/L0.004 µg/L2025-08-27Covina Irrigating Company / 1910142817
PFPeA< 0.003 µg/L0.003 µg/L2025-08-27TVMWD / 1910142818
PFPeS< 0.004 µg/L0.004 µg/L2025-08-27MWD Intertie / 1910142816
PFTA< 0.008 µg/L0.008 µg/L2025-08-27Covina Irrigating Company / 1910142817
PFTrDA< 0.007 µg/L0.007 µg/L2025-08-27TVMWD / 1910142818
PFUnA< 0.002 µg/L0.002 µg/L2025-08-27MWD Intertie / 1910142816
lithium< 9 µg/L9 µg/L2025-08-27Covina Irrigating Company / 1910142817

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) 0.0021 mg/L2024-01-01 – 2026-12-312026Q3
Lead (PB90) 0.0012 mg/L2026-01-01 – 2026-06-302026Q3
Lead (PB90) 0.0021 mg/L2025-07-01 – 2025-12-312026Q3
Lead (PB90) 0 mg/L2021-01-01 – 2023-12-312026Q3
Lead (PB90) 0.0027 mg/L2018-01-01 – 2020-12-312026Q3
Lead (PB90) 0 mg/L2015-01-01 – 2017-12-312026Q3
Lead (PB90) 0.004 mg/L2012-01-01 – 2014-12-312026Q3
Lead (PB90) 0.0042 mg/L2009-01-01 – 2011-12-312026Q3
Twelve most recent imported state laboratory records
SubstancePublished resultSample dateLocation / source
PERCHLORATE6.2 UG/L2026-07-13BASELINE WELL 05 / California DDW laboratory results
NITRATE1.2 MG/L2026-07-13HIGHWAY WELL 01 / California DDW laboratory results
NITRATE0.36 MG/L2026-07-13TVMWD CONNECTION PM21 - TREATED / California DDW laboratory results
PERCHLORATE2.0 UG/L2026-07-13HIGHWAY RESERVOIR BLEND FACILITY / California DDW laboratory results
NITRATE9.5 MG/L2026-07-13BASELINE WELL 05 / California DDW laboratory results
NITRATE3.4 MG/L2026-07-13HIGHWAY RESERVOIR BLEND FACILITY / California DDW laboratory results
NITRATE4.1 MG/L2026-07-13ARTESIA WELL 03 / California DDW laboratory results
NITRATE2.2 MG/L2026-07-13MALONE / California DDW laboratory results
NITRATE4.8 MG/L2026-07-13BASELINE WELL 06 / California DDW laboratory results
NITRATE7.2 MG/L2026-07-13COMBINED RAW INFLUENT TO HIGHWAY TREAT / California DDW laboratory results
PERCHLORATE< 0.500000000 UG/L2026-07-13TVMWD CONNECTION PM21 - TREATED / California DDW laboratory results
PERCHLORATE4.3 UG/L2026-07-13COMBINED RAW INFLUENT TO HIGHWAY TREAT / 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)

Zakhari, George: 760-515-8322

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