Public water system · 090600027
ActiveCastro Ranch
At a glance
Castro Ranch (PWSID 090600027) is an active community water system in California. It reports serving 44 people through 10 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 3 violations for this system; none is health-based, and the most recent began in August 2022.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
44
Service connections
10
Primary source
GW
Groundwater
System type
CWS
Community water system
System record
How does Castro Ranch compare with other water systems in California?
By EPA's size categories, Castro Ranch is a very small system (500 people or fewer). Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active community water system reports serving 6,703 people, so Castro Ranch is well below that figure.
What does “community water system” mean?
A community water system serves at least 15 connections used by year-round residents, or regularly serves at least 25 year-round residents. Homes, apartments and mobile-home parks are served by these. California has 2,997 active community water systems, 40% 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 Castro Ranch?
EPA lists Castro Ranch as privately owned. The EPA Region 09 is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act.
Does Castro Ranch have drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in August 2022. The violations listed here began between June 2022 and August 2022. By type: 3 monitoring. The contaminant or rule involved most often is Revised Total Coliform Rule (3 of them). EPA lists 3 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 |
|---|---|---|---|---|
| 2022-08-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-07-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2022-06-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
All 3 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.
Castro Ranch: frequently asked questions
Who runs Castro Ranch?
Castro Ranch (PWSID 090600027) is a community water system privately owned. It is regulated by the EPA Region 09.
How many people does Castro Ranch serve?
Castro Ranch reports serving 44 people through 10 service connections in California.
Where does Castro 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 Castro Ranch have any drinking water violations?
EPA's records list 3 violations for this system; none is health-based, and the most recent began in August 2022. 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 Castro 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 3 violations for this system; none is health-based, and the most recent began in August 2022. For current results, consult the system's annual water quality report, EPA ECHO, or the EPA Region 09.
Where can I find Castro Ranch's water quality report?
As a community water system, Castro Ranch must deliver an annual water quality report, called a Consumer Confidence Report, to its customers by July 1 each year, covering the previous calendar year. The system can provide a copy on request.
Other water systems in California
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Los Angeles-City, Dept. of Water & Power | Los Angeles | 3,875,566 | Community | Surface water |
| East Bay MUD | Alameda | 1,442,800 | Community | Surface water |
| San Diego, City of | San Diego | 1,385,379 | Community | Surface water |
| San Jose Water | Santa Clara | 1,039,920 | Community | Surface water |
| Sfpuc City Distribution Division | San Francisco | 848,019 | Community | Purchased surface water |
| Eastern Municipal Wd | Riverside | 666,581 | Community | Purchased 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, “Castro Ranch, PWSID 090600027, California”, https://aquacensus.com/water-systems/california/castro-ranch-090600027 (data as of October 1, 2026).