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Community Water System · PWS CA5610040

Cal American Water Co

Rosemead, California 91770 - drinking water served from surface water sources to 66,809 people, tracked in EPA SDWIS and UCMR5.

66,809
People served
10
EPA violations
2
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 10 drinking-water violations at Cal American Water Co, 20% of them health-based - below the California per-system average.

10
Total EPA violations on record
20%
Health-based (MCL / treatment failure)
66,809
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Cal American Water Co

Cal American Water Co is a private-owned community water system that delivers drinking water to 66,809 residents in Rosemead, California (Ventura County) through 20,251 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 10 total violations for this system , of which 2 (20%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 3 monitoring and reporting violations are on file. The most recent violation on record dates to 2022.

The most frequently cited contaminant at this system is Revised Total Coliform Rule, recorded in 3 violations (MON). This system was sampled under EPA's UCMR5 PFAS monitoring program and no PFAS compounds were detected above the minimum reporting level.

Across California, EPA tracks 7,249 public water systems serving 42,404,883 people, with 153,308 cumulative violations and 63,983 health-based violations on record. About 89% of systems in the state carry at least one violation, and state-wide the average per system is 21.1 violations. Statewide, 447 of 694 UCMR5-tested systems have reported PFAS detections (64.4%).

Cal American Water Co's 10 violations sit below the California average.

All figures above are sourced directly from EPA SDWIS and UCMR5 public data releases and are updated as EPA publishes new reporting cycles.

Population Served
66,809
Total Violations
10
Health-Based Violations
2
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Private
Connections
20,251
County
Ventura
School/Daycare
No
MCL Violations
2
Monitoring Violations
3
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Revised Total Coliform Rule MON 3 2022
Coliform (TCR) MCL 2 1997

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 116 samples detected PFAS.

Contaminant Date Result MRL Status
PFDoA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFUnA 9/18/2023 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 9/18/2023 <2.00 ppt 2.00 ppt Not Detected
PFDA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
ADONA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFBA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFPeS 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFOA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
6:2 FTS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
NEtFOSAA 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 9/18/2023 <5.00 ppt 5.00 ppt Not Detected
PFHpS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFTrDA 9/18/2023 <7.00 ppt 7.00 ppt Not Detected
PFMPA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
NFDHA 9/18/2023 <20.00 ppt 20.00 ppt Not Detected
PFEESA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFPeA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFTA 9/18/2023 <8.00 ppt 8.00 ppt Not Detected
PFOS 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 9/18/2023 <6.00 ppt 6.00 ppt Not Detected
PFBS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHpA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFHxS 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
PFNA 9/18/2023 <4.00 ppt 4.00 ppt Not Detected
PFMBA 9/18/2023 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
PFBS 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
PFUnA 6/11/2024 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 6/11/2024 <5.00 ppt 5.00 ppt Not Detected
9Cl-PF3ONS 6/11/2024 <2.00 ppt 2.00 ppt Not Detected
ADONA 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
HFPO-DA 6/11/2024 <5.00 ppt 5.00 ppt Not Detected
PFBA 6/11/2024 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 6/11/2024 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 6/11/2024 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 6/11/2024 <6.00 ppt 6.00 ppt Not Detected
8:2 FTS 6/11/2024 <5.00 ppt 5.00 ppt Not Detected
PFMPA 6/11/2024 <4.00 ppt 4.00 ppt Not Detected
PFPeA 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
PFMBA 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
PFEESA 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
NFDHA 6/11/2024 <20.00 ppt 20.00 ppt Not Detected
PFPeS 6/11/2024 <4.00 ppt 4.00 ppt Not Detected
PFHpS 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
PFHpA 6/11/2024 <3.00 ppt 3.00 ppt Not Detected
6:2 FTS 6/11/2024 <5.00 ppt 5.00 ppt Not Detected

Verify This Water System

The figures above are aggregated from EPA's public databases. To verify the underlying records, or to file a complaint, request a Consumer Confidence Report, or check current monitoring status, go directly to the federal and state regulators that enforce the Safe Drinking Water Act for Cal American Water Co.

Federal Source of Truth

EPA SDWIS, Federal Reports

EPA's Safe Drinking Water Information System (SDWIS) holds the federal compliance record for every regulated public water system. Open the system-level report by PWS ID:

View PWS ID CA5610040 on SDWIS

Source: EPA SDWIS Federal Reports Search

State Regulator

California Drinking Water Authority

California State Water Resources Control Board, Division of Drinking Water is the primacy agency that licenses and inspects Cal American Water Co under EPA-delegated authority.

Open CA regulator portal

Source: California State Water Resources Control Board, Division of Drinking Water

Violation Timeline

Each row links to the EPA SDWIS public record for verification. Cross-reference the contaminant code on EPA's federal report to see violation dates, return-to-compliance status, and enforcement actions.

Year (latest) Contaminant Category Count EPA Record
2022 Revised Total Coliform Rule MON 3 SDWIS / CA5610040 / 8000
1997 Coliform (TCR) MCL 2 SDWIS / CA5610040 / 3100

How Cal American Water Co Compares

Cross-reference this system's record against state averages and the federal MCL framework for context.

Metric Cal American Water Co California avg Federal benchmark
Total violations 10 21.1 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 2 8.8 Indicates a contaminant exceeded a federal MCL
PFAS detection None 64.4% EPA final rule (2024): PFOA/PFOS MCL = 4.0 ppt
Population served 66,809 5,850 Sizing context for compliance burden

Sources: EPA SDWIS and EPA National Primary Drinking Water Regulations (40 CFR Part 141). State averages computed across 7,249 regulated public water systems in California.

Federal MCL reference, Safe Drinking Water Act thresholds
Contaminant Federal MCL / Action Level Note
Lead 0 mg/L (Action Level: 0.015 mg/L) Lead and Copper Rule treatment technique
Arsenic 0.010 mg/L (10 ppb) Health-based MCL since 2006
Total Coliform Treatment technique (RTCR) Indicator organism, monitoring trigger
PFOA / PFOS (PFAS) 4.0 ppt each (final 2024 rule) Compliance deadline 2029 (EPA proposed extending to 2031, not yet final as of May 2026)
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is Cal American Water Co water safe to drink?
Cal American Water Co (PWS ID: CA5610040) has 10 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 66,809 people using Surface Water sources.
How many people does Cal American Water Co serve?
Cal American Water Co serves 66,809 people in Rosemead, California. It is a Private-owned system using Surface Water water sources with 20,251 service connections.
What type of violations does Cal American Water Co have?
Cal American Water Co has 10 total violations: 2 health-based violations (MCL exceedances or treatment failures), 3 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Cal American Water Co water?
No. Cal American Water Co was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does Cal American Water Co use?
Cal American Water Co uses Surface Water as its primary water source. It is classified as a Community Water System (CWS), serving residential populations year-round.
Where does this data come from?
All data comes from the EPA Safe Drinking Water Information System (SDWIS) and the UCMR5 PFAS monitoring program. SDWIS tracks compliance for all public water systems regulated under the Safe Drinking Water Act.
Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. PFAS data from EPA UCMR5 monitoring program (2023-2025). This data is provided for informational purposes only.
Data sourced from EPA SDWIS and UCMR5 PFAS monitoring data. See our methodology for details. Retrieved and formatted by PlainWater Editorial

Every figure on PlainWater is rendered directly from EPA SDWIS drinking-water data, no number is typed in by an editor. This system's figures are rendered directly from EPA SDWIS data, no figure is typed in by an editor. See our editorial standards & corrections policy, the methodology behind these numbers, or report a data error.