Casitas Municipal Water Dist

Published drinking-water records and contacts for Casitas Municipal Water Dist. System CA5610024. Review sources and dates; not a real-time water assessment.

System ID: CA5610024
State or territory: CA
Published population served: 11005
System type (source code): CWS

Published records and dates

PFAS / lithium (EPA UCMR 5): 240 — 2023-03-07 – 2024-11-13
Lead and copper monitoring summaries: 81 — 1992-01-01 – 2023-12-31
California DDW laboratory results: 448 — 2026-01-05 – 2026-06-30

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
Substance	Published result	Reporting limit	Sample date	Sampling location
11Cl-PF3OUdS	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
4:2 FTS	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
6:2 FTS	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
8:2 FTS	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
9Cl-PF3ONS	< 0.002 µg/L	0.002 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
ADONA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
HFPO-DA	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
NEtFOSAA	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
NFDHA	< 0.02 µg/L	0.02 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
NMeFOSAA	< 0.006 µg/L	0.006 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFBA	< 0.005 µg/L	0.005 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFBS	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFDA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFDoA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFEESA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFHpA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFHpS	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFHxA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFHxS	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFMBA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFMPA	< 0.004 µg/L	0.004 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFNA	< 0.004 µg/L	0.004 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFOA	< 0.004 µg/L	0.004 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFOS	< 0.004 µg/L	0.004 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFPeA	< 0.003 µg/L	0.003 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFPeS	< 0.004 µg/L	0.004 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFTA	< 0.008 µg/L	0.008 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFTrDA	< 0.007 µg/L	0.007 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
PFUnA	< 0.002 µg/L	0.002 µg/L	2024-11-13	Marion R. Walker Pressure Filtration Plant / CA5610024006006
lithium	14 µg/L	9 µg/L	2023-12-12	Marion R. Walker Pressure Filtration Plant / CA5610024006006

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
Substance	Published 90th percentile	Monitoring period	Source quarter
Lead (PB90)	0 mg/L	2021-01-01 – 2023-12-31	2026Q3
Lead (PB90)	0 mg/L	2018-01-01 – 2020-12-31	2026Q3
Lead (PB90)	0 mg/L	2015-01-01 – 2017-12-31	2026Q3
Lead (PB90)	0.0012 mg/L	2012-01-01 – 2014-12-31	2026Q3
Lead (PB90)	0.0008 mg/L	2009-01-01 – 2011-12-31	2026Q3
Lead (PB90)	0.001 mg/L	2008-01-01 – 2008-12-31	2026Q3
Lead (PB90)	0.0016 mg/L	2007-01-01 – 2007-12-31	2026Q3
Lead (PB90)	0.0012 mg/L	2006-01-01 – 2006-12-31	2026Q3

Twelve most recent imported state laboratory records
Substance	Published result	Sample date	Location / source
NITRATE	0.7 MG/L	2026-06-30	MM WELL 03 - NO3 BLEND / California DDW laboratory results
NITRATE	0.8 MG/L	2026-06-23	MM WELL 03 - NO3 BLEND / California DDW laboratory results
PERFLUOROPENTANOIC ACID (PFPEA)	< 2.000000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / California DDW laboratory results
PERFLUOROHEXANE SULFONIC ACID (PFHxS)	< 2.000000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / California DDW laboratory results
PERFLUOROUNDECANOIC ACID (PFUNA)	< 1.800000000 NG/L	2026-06-16	MM WELL 03 / California DDW laboratory results
9CL-PF3ONS	< 1.800000000 NG/L	2026-06-16	MM WELL 03 / California DDW laboratory results
PERFLUOROPENTANESULFONIC ACID (PFPES)	< 1.800000000 NG/L	2026-06-16	MM WELL 03 / California DDW laboratory results
PERFLUORO PFMPA	< 2.000000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / California DDW laboratory results
PERFLUOROBUTANE SULFONIC ACID (PFBS)	< 1.800000000 NG/L	2026-06-16	MM WELL 03 / California DDW laboratory results
PERFLUOROTRIDECANOIC ACID (PFTRDA)	< 1.800000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / California DDW laboratory results
PERFLUORODODECANOIC ACID (PFDOA)	< 2.000000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / California DDW laboratory results
PERFLUOROBUTANE SULFONIC ACID (PFBS)	< 2.000000000 NG/L	2026-06-16	CASITAS RESERVOIR RAW / 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

3 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 / record	Period	Recorded status	Health-based (EPA classification)	Source quarter
Surface Water Treatment Rule / Monitoring of Treatment (SWTR-Filter)	2024-12-01 – 2024-12-31	Archived	No	2026Q3
Stage 2 Disinfectants and Disinfection Byproducts Rule / Maximum Contaminant Level Violation, Average	2023-10-01 – 2023-12-31	Resolved	Yes	2026Q3
Revised Total Coliform Rule / Monitoring, Routine (RTCR)	2022-02-01 – 2022-02-28	Resolved	No	2026Q3

Source dates and refresh checks

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

EPA SDWIS lead/copper summaries and service areas — source period: — – —; last checked: 2026-10-17
EPA SDWIS contacts and compliance records — source period: — – —; last checked: 2026-10-17
EPA UCMR 5 sample results — source period: 2023-01-03 – 2026-06-17; last checked: 2026-10-17
California DDW laboratory results — last successful check: 2026-10-17

Administrative contact (EPA filing)

Flood, Michael: 805-649-2251

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