PlainWater

Transient Non-Community Water System · PWS CA3600044

Cal Trans - Desert Oasis

San Bernardino, California 92408 - drinking water served from groundwater sources to 2,000 people, tracked in EPA SDWIS and UCMR5.

2,000
People served
12
EPA violations
2
Health-based
Untested
UCMR5 result

The verdict

EPA records 12 drinking-water violations at Cal Trans - Desert Oasis, 17% of them health-based - below the California per-system average.

12
Total EPA violations on record
17%
Health-based (MCL / treatment failure)
2,000
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Cal Trans - Desert Oasis

Cal Trans - Desert Oasis is a state-owned transient non-community water system that delivers drinking water to 2,000 residents in San Bernardino, California (San Bernardino County) through 1 service connections. Its water is drawn from groundwater sources. EPA's Safe Drinking Water Information System records 12 total violations for this system , of which 2 (17%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 10 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 Coliform (TCR), recorded in 8 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. Statewide, 447 of 694 UCMR5-tested systems have reported PFAS detections (64.4%).

Cal Trans - Desert Oasis's 12 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
2,000
Total Violations
12
Health-Based Violations
2
Water Source
Groundwater

System Details

System Type
Transient Non-Community
Owner Type
State
Connections
1
County
San Bernardino
School/Daycare
No
MCL Violations
2
Monitoring Violations
10
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Coliform (TCR) MR 8 2012
Nitrate MR 2 2022
Coliform (TCR) MCL 2 2013

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 Trans - Desert Oasis.

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 CA3600044 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 Trans - Desert Oasis 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 Nitrate MR 2 SDWIS / CA3600044 / 1040
2013 Coliform (TCR) MCL 2 SDWIS / CA3600044 / 3100
2012 Coliform (TCR) MR 8 SDWIS / CA3600044 / 3100

How Cal Trans - Desert Oasis Compares

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

Metric Cal Trans - Desert Oasis California avg Federal benchmark
Total violations 12 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 2,000 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 Trans - Desert Oasis water safe to drink?
Cal Trans - Desert Oasis (PWS ID: CA3600044) has 12 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 2,000 people using Groundwater sources.
How many people does Cal Trans - Desert Oasis serve?
Cal Trans - Desert Oasis serves 2,000 people in San Bernardino, California. It is a State-owned system using Groundwater water sources with 1 service connections.
What type of violations does Cal Trans - Desert Oasis have?
Cal Trans - Desert Oasis has 12 total violations: 2 health-based violations (MCL exceedances or treatment failures), 10 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Cal Trans - Desert Oasis water?
No PFAS testing data is available for Cal Trans - Desert Oasis under the EPA's UCMR5 monitoring program.
What water source does Cal Trans - Desert Oasis use?
Cal Trans - Desert Oasis uses Groundwater as its primary water source. It is classified as a Transient Non-Community Water System, serving transient populations.
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. 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.