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City of Rio Vista

Published drinking-water records and contacts for City of Rio Vista. System CA4810004. Review sources and dates; not a real-time water assessment.

System ID
CA4810004
State or territory
CA
Published population served
10489
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/L2024-07-09Well 14 / EP014
4:2 FTS< 0.003 µg/L0.003 µg/L2024-07-09Well 13 / EP007
6:2 FTS< 0.005 µg/L0.005 µg/L2024-07-09Well 14 / EP014
8:2 FTS< 0.005 µg/L0.005 µg/L2024-07-09Well 11 / EP005
9Cl-PF3ONS< 0.002 µg/L0.002 µg/L2024-07-09Well 15 / EP015
ADONA< 0.003 µg/L0.003 µg/L2024-07-09Well 13 / EP007
HFPO-DA< 0.005 µg/L0.005 µg/L2024-07-09Blend Facility / EP010
NEtFOSAA< 0.005 µg/L0.005 µg/L2024-07-09Well 13 / EP007
NFDHA< 0.02 µg/L0.02 µg/L2024-07-09Amador Tank / EP017
NMeFOSAA< 0.006 µg/L0.006 µg/L2024-07-09Well 11 / EP005
PFBA< 0.005 µg/L0.005 µg/L2024-07-09Well 15 / EP015
PFBS< 0.003 µg/L0.003 µg/L2024-07-09Amador Tank / EP017
PFDA< 0.003 µg/L0.003 µg/L2024-07-09Amador Tank / EP017
PFDoA< 0.003 µg/L0.003 µg/L2024-07-09Well 14 / EP014
PFEESA< 0.003 µg/L0.003 µg/L2024-07-09Well 10 Treatment / EP004
PFHpA< 0.003 µg/L0.003 µg/L2024-07-09Well 13 / EP007
PFHpS< 0.003 µg/L0.003 µg/L2024-07-09Well 10 Treatment / EP004
PFHxA< 0.003 µg/L0.003 µg/L2024-07-09Well 11 / EP005
PFHxS< 0.003 µg/L0.003 µg/L2024-07-09Well 14 / EP014
PFMBA< 0.003 µg/L0.003 µg/L2024-07-09Well 10 Treatment / EP004
PFMPA< 0.004 µg/L0.004 µg/L2024-07-09Well 15 / EP015
PFNA< 0.004 µg/L0.004 µg/L2024-07-09Well 15 / EP015
PFOA< 0.004 µg/L0.004 µg/L2024-07-09Well 15 / EP015
PFOS< 0.004 µg/L0.004 µg/L2024-07-09Well 15 / EP015
PFPeA< 0.003 µg/L0.003 µg/L2024-07-09Well 14 / EP014
PFPeS< 0.004 µg/L0.004 µg/L2024-07-09Well 14 / EP014
PFTA< 0.008 µg/L0.008 µg/L2024-07-09Well 10 Treatment / EP004
PFTrDA< 0.007 µg/L0.007 µg/L2024-07-09Well 14 / EP014
PFUnA< 0.002 µg/L0.002 µg/L2024-07-09Well 13 / EP007
lithium15 µg/L9 µg/L2024-07-09Well 14 / EP014

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/L2026-01-01 – 2028-12-312026Q3
Lead (PB90) 0 mg/L2020-01-01 – 2022-12-312026Q3
Lead (PB90) 0 mg/L2017-01-01 – 2019-12-312026Q3
Lead (PB90) 0.0009 mg/L2014-01-01 – 2016-12-312026Q3
Lead (PB90) 0.006 mg/L2011-01-01 – 2013-12-312026Q3
Lead (PB90) 0.0101 mg/L2008-01-01 – 2010-12-312026Q3
Lead (PB90) 0.002 mg/L2003-01-01 – 2005-12-312026Q3
Lead (PB90) 0.0023 mg/L2003-01-01 – 2003-12-312026Q3
Twelve most recent imported state laboratory records
SubstancePublished resultSample dateLocation / source
NITRATE2.2 MG/L2026-06-25WELL 13 / California DDW laboratory results
NITRATE0.5 MG/L2026-06-25WELL 15 / California DDW laboratory results
ARSENIC8.1 UG/L2026-06-10WELL 10 ARSENIC WTP TREATED EFFLUENT / California DDW laboratory results
ARSENIC15 UG/L2026-06-10WELL 10 / California DDW laboratory results
ARSENIC7.2 UG/L2026-06-08BOOSTER STATION BLEND FACILITY EFFLUENT / California DDW laboratory results
ARSENIC7.6 UG/L2026-06-08WELL 14 / California DDW laboratory results
ARSENIC8.4 UG/L2026-06-08WELL 15 / California DDW laboratory results
ARSENIC8.2 UG/L2026-06-08AMADOR TANK / California DDW laboratory results
ARSENIC8.3 UG/L2026-06-08WELL 13 / California DDW laboratory results
ARSENIC5.1 UG/L2026-06-08WELL 11 / California DDW laboratory results
PERFLUOROUNDECANOIC ACID (PFUNA)< 2.000000000 NG/L2026-05-21WELL 11 / California DDW laboratory results
PERFLUOROTRIDECANOIC ACID (PFTRDA)< 2.000000000 NG/L2026-05-21WELL 11 / 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
Lead and Copper Rule / Follow-up Or Routine LCR Tap M/R2025-10-01 – —UnaddressedNo2026Q3

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)

Malcolm, Greg: 707-374-6451

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