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Community Water System · PWS CA0110006

City of Hayward

Hayward, California 94541-5007 - drinking water served from surface water sources to 162,954 people, tracked in EPA SDWIS and UCMR5.

162,954
People served
6
EPA violations
0
Health-based
No PFAS
UCMR5 result

The verdict

EPA records 6 drinking-water violations at City of Hayward - below the California per-system average.

6
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
162,954
People served by this system
0
PFAS compounds detected (UCMR5)

Water Quality Snapshot: City of Hayward

City of Hayward is a local-owned community water system that delivers drinking water to 162,954 residents in Hayward, California (Alameda County) through 36,838 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 6 total violations for this system , of which 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed.

No specific contaminant violations have been recorded in EPA's detailed violation register for this system. 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%).

City of Hayward's 6 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
162,954
Total Violations
6
Health-Based Violations
0
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Local
Connections
36,838
County
Alameda
School/Daycare
No
MCL Violations
0
Monitoring Violations
0
Treatment Tech Violations
0

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 174 samples detected PFAS.

Contaminant Date Result MRL Status
PFTA 7/1/2025 <8.00 ppt 8.00 ppt Not Detected
PFEESA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
4:2 FTS 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFMPA 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFMBA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
NFDHA 7/1/2025 <20.00 ppt 20.00 ppt Not Detected
PFPeS 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
PFHpS 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFBA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 7/1/2025 <7.00 ppt 7.00 ppt Not Detected
PFHxA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
NEtFOSAA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFOA 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
NMeFOSAA 7/1/2025 <6.00 ppt 6.00 ppt Not Detected
PFHpA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFHxS 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
11Cl-PF3OUdS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFOS 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
HFPO-DA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFDA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFDoA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFUnA 7/1/2025 <2.00 ppt 2.00 ppt Not Detected
PFBS 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 7/1/2025 <2.00 ppt 2.00 ppt Not Detected
ADONA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFNA 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
HFPO-DA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
6:2 FTS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFTrDA 7/1/2025 <7.00 ppt 7.00 ppt Not Detected
NEtFOSAA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
NMeFOSAA 7/1/2025 <6.00 ppt 6.00 ppt Not Detected
PFUnA 7/1/2025 <2.00 ppt 2.00 ppt Not Detected
11Cl-PF3OUdS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
ADONA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFTA 7/1/2025 <8.00 ppt 8.00 ppt Not Detected
PFBA 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
4:2 FTS 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
8:2 FTS 7/1/2025 <5.00 ppt 5.00 ppt Not Detected
PFMPA 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
PFPeA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFDoA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
9Cl-PF3ONS 7/1/2025 <2.00 ppt 2.00 ppt Not Detected
PFHxA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFMBA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFDA 7/1/2025 <3.00 ppt 3.00 ppt Not Detected
PFOA 7/1/2025 <4.00 ppt 4.00 ppt Not Detected
PFOS 7/1/2025 <4.00 ppt 4.00 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 City of Hayward.

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 CA0110006 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 City of Hayward under EPA-delegated authority.

Open CA regulator portal

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

How City of Hayward Compares

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

Metric City of Hayward California avg Federal benchmark
Total violations 6 21.1 SDWA compliance, any non-zero count is a recorded breach
Health-based violations 0 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 162,954 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 City of Hayward water safe to drink?
City of Hayward (PWS ID: CA0110006) has 6 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 162,954 people using Surface Water sources.
How many people does City of Hayward serve?
City of Hayward serves 162,954 people in Hayward, California. It is a Local-owned system using Surface Water water sources with 36,838 service connections.
What type of violations does City of Hayward have?
City of Hayward has 6 total violations: 0 health-based violations (MCL exceedances or treatment failures), 0 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in City of Hayward water?
No. City of Hayward was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does City of Hayward use?
City of Hayward 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.