Public water system · CA4000226
ActivePacific Dunes Ranch
At a glance
Pacific Dunes Ranch (PWSID CA4000226) is an active non-transient non-community water system in San Luis Obispo County, California. It reports serving 89 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 8 violations for this system; none is health-based, and the most recent began in November 2008.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
89
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Pacific Dunes Ranch compare with other water systems in San Luis Obispo County?
By EPA's size categories, Pacific Dunes Ranch is a very small system (500 people or fewer). San Luis Obispo County has 171 active public water systems. Its population served is well below the county average of 2,038 people per system, and accounts for less than 0.1% of the 348,510 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Pacific Dunes Ranch is well below that figure.
What does “non-transient non-community water system” mean?
A non-transient non-community water system regularly serves at least 25 of the same people for more than six months a year, but not where they live. Schools, factories, office buildings and hospitals with their own supply are typical examples. California has 1,466 active non-transient non-community water systems, 20% of the state's 7,479 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 6,179 California systems (83%) list groundwater as their primary source.
Who owns and regulates Pacific Dunes Ranch?
EPA lists Pacific Dunes Ranch as privately owned. The CA state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 130 of the 171 active systems in San Luis Obispo County (76%) are also privately owned.
Does Pacific Dunes Ranch have drinking water violations?
EPA's records list 8 violations for this system; none is health-based, and the most recent began in November 2008. The violations listed here began between July 2004 and November 2008. By type: 7 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Total coliform bacteria (TCR) (7 of them). EPA lists 8 as resolved. Resolved means at least one resolving action is on record: the system returned to compliance, the rule no longer applies, or no further action was needed.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2008-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-08-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2008-02-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-09-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2007-02-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2006-04-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2005-11-01 | Monitoring and reportingMonitoring, Routine Major (TCR) · code 23 | Total coliform bacteria (TCR)code 3100 | No | Resolved |
| 2004-07-01 | Public notice, recordkeeping or otherConsumer Confidence Report Complete Failure to Report · code 71 | Consumer Confidence Rulecode 7000 | No | Resolved |
All 8 violations in EPA's records, newest first.Labels and codes come from EPA's SDWIS reference tables. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found. "Health-based" marks violations of a legal limit or required treatment.
Pacific Dunes Ranch: frequently asked questions
Who runs Pacific Dunes Ranch?
Pacific Dunes Ranch (PWSID CA4000226) is a non-transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Pacific Dunes Ranch serve?
Pacific Dunes Ranch reports serving 89 people through 1 service connection in San Luis Obispo County, California.
Where does Pacific Dunes Ranch get its water?
EPA SDWIS lists this system's primary water source as groundwater. Groundwater means the system draws its water from wells or springs fed by underground aquifers.
Does Pacific Dunes Ranch have any drinking water violations?
EPA's records list 8 violations for this system; none is health-based, and the most recent began in November 2008. A monitoring or reporting violation means a required test or report was missed or late; it does not by itself mean a contaminant was found.
Is Pacific Dunes Ranch's water safe to drink?
AquaCensus shows EPA compliance records, not current water test results, so it cannot say whether the water is safe at a given moment. EPA's records list 8 violations for this system; none is health-based, and the most recent began in November 2008. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Pacific Dunes Ranch's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Pacific Dunes Ranch is a non-transient non-community water system, so it is not required to publish one; like every public water system, it must notify the people it serves about violations under EPA's public notification rules.
Other water systems in San Luis Obispo County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Margarita Recreation Area | San Luis Obispo | 50,001 | Transient non-community | Groundwater |
| San Luis Obispo Water Department | San Luis Obispo | 47,788 | Community | Surface water |
| City of Paso Robles Water Division | San Luis Obispo | 31,176 | Community | Surface water |
| Atascadero Mutual Water Co | San Luis Obispo | 30,618 | Community | Groundwater |
| City of Arroyo Grande Utilities Division | San Luis Obispo | 17,963 | Community | Purchased surface water |
| California Mens Colony | San Luis Obispo | 15,000 | Community | Surface water |
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About this data
Source: U.S. EPA Safe Drinking Water Information System (SDWIS) and SDWA violation records, via EPA ECHO, as published October 1, 2026 — AquaCensus refreshes it quarterly. See the methodology for how records are matched, cleaned and scored.
Cite as: AquaCensus, “Pacific Dunes Ranch, PWSID CA4000226, California”, https://aquacensus.com/water-systems/california/pacific-dunes-ranch-ca4000226 (data as of October 1, 2026).