PlainWater

Non-Transient Non-Community Water System · PWS CA4000825

Daou Vineyards, LLC

Paso Robles, California 93446 - drinking water served from groundwater sources to 1,025 people, tracked in EPA SDWIS and UCMR5.

1,025
People served
2
EPA violations
0
Health-based
Untested
UCMR5 result

The verdict

EPA records 2 drinking-water violations at Daou Vineyards, LLC - below the California per-system average.

2
Total EPA violations on record
0%
Health-based (MCL / treatment failure)
1,025
People served by this system
N/A
PFAS compounds detected (UCMR5)

Water Quality Snapshot: Daou Vineyards, LLC

Daou Vineyards, LLC is a private-owned non-transient non-community water system that delivers drinking water to 1,025 residents in Paso Robles, California (San Luis Obispo County) through 7 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 0 (0%) are health-based, meaning a contaminant exceeded an EPA Maximum Contaminant Level or a required treatment technique failed. A further 2 monitoring and reporting violations are on file. The most recent violation on record dates to 2018.

The most frequently cited contaminant at this system is Nitrate, recorded in 2 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%).

Daou Vineyards, LLC's 2 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
1,025
Total Violations
2
Health-Based Violations
0
Water Source
Groundwater

System Details

System Type
Non-Transient Non-Community
Owner Type
Private
Connections
7
County
San Luis Obispo
School/Daycare
No
MCL Violations
0
Monitoring Violations
2
Treatment Tech Violations
0

Violation History

Contaminant violations recorded by EPA.

Contaminant Category Count Latest
Nitrate MR 2 2018

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 Daou Vineyards, LLC.

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 CA4000825 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 Daou Vineyards, LLC 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
2018 Nitrate MR 2 SDWIS / CA4000825 / 1040

How Daou Vineyards, LLC Compares

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

Metric Daou Vineyards, LLC California avg Federal benchmark
Total violations 2 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 1,025 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 Daou Vineyards, LLC water safe to drink?
Daou Vineyards, LLC (PWS ID: CA4000825) has 2 recorded violations in the EPA SDWIS database. No PFAS contamination was detected in UCMR5 testing. This system serves 1,025 people using Groundwater sources.
How many people does Daou Vineyards, LLC serve?
Daou Vineyards, LLC serves 1,025 people in Paso Robles, California. It is a Private-owned system using Groundwater water sources with 7 service connections.
What type of violations does Daou Vineyards, LLC have?
Daou Vineyards, LLC has 2 total violations: 0 health-based violations (MCL exceedances or treatment failures), 2 monitoring/reporting violations, and 0 treatment technique violations. Health-based violations indicate contaminant levels exceeded EPA safe limits.
Has PFAS been detected in Daou Vineyards, LLC water?
No PFAS testing data is available for Daou Vineyards, LLC under the EPA's UCMR5 monitoring program.
What water source does Daou Vineyards, LLC use?
Daou Vineyards, LLC uses Groundwater as its primary water source. It is classified as a Non-Transient Non-Community Water System, serving the same people for at least 6 months per year.
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.