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CAL-WATER SERVICE CO.-MARYSVILLE

PWS ID: CA5810001 · SAN JOSE, California 95112

CAL-WATER SERVICE CO.-MARYSVILLE serves 12,419 people in SAN JOSE, California using Groundwater water sources. It has 2 recorded EPA violations, including 2 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: CAL-WATER SERVICE CO.-MARYSVILLE

CAL-WATER SERVICE CO.-MARYSVILLE is a private-owned community water system that delivers drinking water to 12,419 residents in SAN JOSE, California (Yuba County) through 3,721 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 2 total violations for this system , of which 2 (100%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. The most recent violation on record dates to 1993.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 2 violations (MCL, health-based). 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. CAL-WATER SERVICE CO.-MARYSVILLE's 2 violations sit below the California average. Statewide, 447 of 694 UCMR5-tested systems have reported PFAS detections (64.4%). 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
12,419
Total Violations
2
Health-Based Violations
2
Water Source
Groundwater

System Details

System Type
Community
Owner Type
Private
Connections
3,721
County
Yuba
School/Daycare
No
MCL Violations
2
Monitoring Violations
0
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MCL 2 1993

PFAS Testing Results (UCMR5)

Results from EPA's Fifth Unregulated Contaminant Monitoring Rule. 0 of 480 samples detected PFAS.

Contaminant Date Result MRL Status
PFTrDA 9/30/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFHxS 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
lithium 9/30/2024 <9 µg/L 9 µg/L Not Detected
NFDHA 9/30/2024 <0.02 µg/L 0.02 µg/L Not Detected
PFEESA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMBA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMPA 9/30/2024 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
6:2 FTS 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFNA 9/30/2024 <0.004 µg/L 0.004 µg/L Not Detected
NEtFOSAA 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFBS 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFTA 9/30/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFHpS 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeS 9/30/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFBA 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
HFPO-DA 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
ADONA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
9Cl-PF3ONS 9/30/2024 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/30/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFUnA 9/30/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFHxA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFOA 9/30/2024 <0.004 µg/L 0.004 µg/L Not Detected
NMeFOSAA 9/30/2024 <0.006 µg/L 0.006 µg/L Not Detected
PFHpA 9/30/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFOS 9/30/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFMBA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFPeA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFMPA 9/26/2024 <0.004 µg/L 0.004 µg/L Not Detected
8:2 FTS 9/26/2024 <0.005 µg/L 0.005 µg/L Not Detected
4:2 FTS 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
NMeFOSAA 9/26/2024 <0.006 µg/L 0.006 µg/L Not Detected
NEtFOSAA 9/26/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFTA 9/26/2024 <0.008 µg/L 0.008 µg/L Not Detected
PFTrDA 9/26/2024 <0.007 µg/L 0.007 µg/L Not Detected
PFBA 9/26/2024 <0.005 µg/L 0.005 µg/L Not Detected
PFOS 9/26/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFOA 9/26/2024 <0.004 µg/L 0.004 µg/L Not Detected
PFDA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFDoA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFHxA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
PFUnA 9/26/2024 <0.002 µg/L 0.002 µg/L Not Detected
11Cl-PF3OUdS 9/26/2024 <0.005 µg/L 0.005 µg/L Not Detected
9Cl-PF3ONS 9/26/2024 <0.002 µg/L 0.002 µg/L Not Detected
PFHpA 9/26/2024 <0.003 µg/L 0.003 µg/L Not Detected
HFPO-DA 9/26/2024 <0.005 µg/L 0.005 µg/L 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-WATER SERVICE CO.-MARYSVILLE.

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 CA5810001 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-WATER SERVICE CO.-MARYSVILLE 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
1993 Coliform (TCR) MCL 2 SDWIS / CA5810001 / 3100

How CAL-WATER SERVICE CO.-MARYSVILLE Compares

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

Metric CAL-WATER SERVICE CO.-MARYSVILLE California avg Federal benchmark
Total violations 2 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 12,419 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
Nitrate (as N) 10 mg/L Acute health risk for infants

Frequently Asked Questions

Is CAL-WATER SERVICE CO.-MARYSVILLE water safe to drink? ▼
CAL-WATER SERVICE CO.-MARYSVILLE (PWS ID: CA5810001) has 2 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 12,419 people using Groundwater sources.
How many people does CAL-WATER SERVICE CO.-MARYSVILLE serve? ▼
CAL-WATER SERVICE CO.-MARYSVILLE serves 12,419 people in SAN JOSE, California. It is a Private-owned system using Groundwater water sources with 3,721 service connections.
What type of violations does CAL-WATER SERVICE CO.-MARYSVILLE have? ▼
CAL-WATER SERVICE CO.-MARYSVILLE has 2 total violations: 2 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 CAL-WATER SERVICE CO.-MARYSVILLE water? ▼
No. CAL-WATER SERVICE CO.-MARYSVILLE was tested for PFAS under the EPA's UCMR5 monitoring program and no PFAS contamination was detected.
What water source does CAL-WATER SERVICE CO.-MARYSVILLE use? ▼
CAL-WATER SERVICE CO.-MARYSVILLE uses Groundwater 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.

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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.

Read our methodology — how this data is sourced, computed, and verified.

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Data sourced from $official public datasets. See our methodology for details. Retrieved and formatted by Kiznis Studio Editorial