PlainWater

U.S.N., SAN NICOLAS ISLAND

PWS ID: CA5610702 · POINT MUGU, California 93042

U.S.N., SAN NICOLAS ISLAND serves 254 people in POINT MUGU, California using Surface Water water sources. It has 24 recorded EPA violations, including 8 health-based violations. No PFAS contamination was detected in UCMR5 testing.

Water Quality Snapshot: U.S.N., SAN NICOLAS ISLAND

U.S.N., SAN NICOLAS ISLAND is a federal-owned community water system that delivers drinking water to 254 residents in POINT MUGU, California (Ventura County) through 106 service connections. Its water is drawn from surface water sources. EPA's Safe Drinking Water Information System records 24 total violations for this system , of which 8 (33%) are health-based — meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 14 monitoring and reporting violations are on file. The most recent violation on record dates to 2012.

The most frequently cited contaminant at this system is Coliform (TCR), recorded in 12 violations (MR). This system has not yet been sampled under EPA's UCMR5 PFAS monitoring program, so no PFAS detection data is available here.

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. U.S.N., SAN NICOLAS ISLAND's 24 violations sit above 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
254
Total Violations
24
Health-Based Violations
8
Water Source
Surface Water

System Details

System Type
Community
Owner Type
Federal
Connections
106
County
Ventura
School/Daycare
No
MCL Violations
6
Monitoring Violations
14
Treatment Tech Violations
2

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 12 2003
Coliform (TCR) MCL 4 2003
TTHM MCL 2 2005
Surface Water Treatment Rule MR 2 2012
Surface Water Treatment Rule TT 2 1993

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 U.S.N., SAN NICOLAS ISLAND.

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 CA5610702 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 U.S.N., SAN NICOLAS ISLAND 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
2012 Surface Water Treatment Rule MR 2 SDWIS / CA5610702 / 0200
2005 TTHM MCL 2 SDWIS / CA5610702 / 2950
2003 Coliform (TCR) MR 12 SDWIS / CA5610702 / 3100
2003 Coliform (TCR) MCL 4 SDWIS / CA5610702 / 3100
1993 Surface Water Treatment Rule TT 2 SDWIS / CA5610702 / 0200

How U.S.N., SAN NICOLAS ISLAND Compares

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

Metric U.S.N., SAN NICOLAS ISLAND California avg Federal benchmark
Total violations 24 21.1 SDWA compliance — any non-zero count is a recorded breach
Health-based violations 8 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 254 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 U.S.N., SAN NICOLAS ISLAND water safe to drink?
U.S.N., SAN NICOLAS ISLAND (PWS ID: CA5610702) has 24 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 254 people using Surface Water sources.
How many people does U.S.N., SAN NICOLAS ISLAND serve?
U.S.N., SAN NICOLAS ISLAND serves 254 people in POINT MUGU, California. It is a Federal-owned system using Surface Water water sources with 106 service connections.
What type of violations does U.S.N., SAN NICOLAS ISLAND have?
U.S.N., SAN NICOLAS ISLAND has 24 total violations: 8 health-based violations (MCL exceedances or treatment failures), 14 monitoring/reporting violations, and 2 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in U.S.N., SAN NICOLAS ISLAND water?
No PFAS testing data is available for U.S.N., SAN NICOLAS ISLAND under the EPA's UCMR5 monitoring program.
What water source does U.S.N., SAN NICOLAS ISLAND use?
U.S.N., SAN NICOLAS ISLAND 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.

Explore PlainWater

Data Sources: EPA Safe Drinking Water Information System (SDWIS), Q4 2025. This data is provided for informational purposes only.

Related

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