Public water system · CA2100576
ActiveTomales Tin Building
At a glance
Tomales Tin Building (PWSID CA2100576) is an active transient non-community water system in Marin County, California. It reports serving 82 people through 3 service connections. Its primary water source is groundwater, and EPA lists it as privately owned. EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in September 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
82
Service connections
3
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
How does Tomales Tin Building compare with other water systems in Marin County?
By EPA's size categories, Tomales Tin Building is a very small system (500 people or fewer). Marin County has 46 active public water systems. Its population served is well below the county average of 6,203 people per system, and accounts for less than 0.1% of the 285,353 people reported by systems filed under the county. Across California, the 7,479 active systems average 5,706 people each. Nationally, the average active transient non-community water system reports serving 144 people, so Tomales Tin Building is about 43% below that figure.
What does “transient non-community water system” mean?
A transient non-community water system serves places where people do not stay long, such as gas stations and campgrounds, and regularly serves at least 25 people a day for at least 60 days a year. California has 3,016 active transient non-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 Tomales Tin Building?
EPA lists Tomales Tin Building 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. 22 of the 46 active systems in Marin County (48%) are also privately owned.
Does Tomales Tin Building have drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in September 2019. The violations listed here began between September 2015 and September 2019. By type: 1 monitoring and 1 contaminant level above the legal limit. The contaminants or rules involved are Revised Total Coliform Rule and Total coliform bacteria (TCR). EPA lists 2 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 |
|---|---|---|---|---|
| 2019-09-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2015-09-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Acute (TCR) · code 21 | Total coliform bacteria (TCR)code 3100 | Yes | Resolved |
All 2 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.
Tomales Tin Building: frequently asked questions
Who runs Tomales Tin Building?
Tomales Tin Building (PWSID CA2100576) is a transient non-community water system privately owned. It is regulated by the CA state drinking water program.
How many people does Tomales Tin Building serve?
Tomales Tin Building reports serving 82 people through 3 service connections in Marin County, California.
Where does Tomales Tin Building 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 Tomales Tin Building have any drinking water violations?
EPA's records list 2 violations for this system; 1 is health-based, and the most recent began in September 2019. 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 Tomales Tin Building'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 2 violations for this system; 1 is health-based, and the most recent began in September 2019. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Tomales Tin Building's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Tomales Tin Building is a 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 Marin County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Marin Municipal Water District | Marin | 186,895 | Community | Surface water |
| North Marin Water District | Marin | 61,691 | Community | Surface water |
| Nps Ggnra | Marin | 18,447 | Community | Purchased surface water |
| Bolinas Community PUD | Marin | 2,483 | Community | Surface water |
| North Marin Wd - Pt. Reyes | Marin | 1,841 | Community | Groundwater |
| Csp - Angel Island St Park | Marin | 1,622 | Transient non-community | Groundwater |
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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, “Tomales Tin Building, PWSID CA2100576, California”, https://aquacensus.com/water-systems/california/tomales-tin-building-ca2100576 (data as of October 1, 2026).