Public water system · CA4900716
ActiveCinnabar Elementary School
At a glance
Cinnabar Elementary School (PWSID CA4900716) is an active non-transient non-community water system in Sonoma County, California. It reports serving 228 people through 2 service connections. Its primary water source is groundwater, and EPA lists it as owned by a local government. EPA's records list 6 violations for this system; 4 are health-based, and the most recent began in July 2019.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
228
Service connections
2
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Cinnabar Elementary School compare with other water systems in Sonoma County?
By EPA's size categories, Cinnabar Elementary School is a very small system (500 people or fewer). Sonoma County has 441 active public water systems. Its population served is well below the county average of 1,092 people per system, and accounts for less than 0.1% of the 481,435 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 Cinnabar Elementary School is about half of 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 Cinnabar Elementary School?
EPA lists Cinnabar Elementary School as owned by a local government. 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. 58 of the 441 active systems in Sonoma County (13%) are also owned by a local government.
Does Cinnabar Elementary School have drinking water violations?
EPA's records list 6 violations for this system; 4 are health-based, and the most recent began in July 2019. The violations listed here began between August 1984 and July 2019. By type: 4 contaminant level above the legal limit, 1 monitoring and reporting and 1 public notice, recordkeeping or other. The contaminant or rule involved most often is Arsenic (4 of them). EPA lists 5 as resolved and 1 as archived. 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. Archived means the violation was not marked resolved but is more than five years past the end of the noncompliance period, so it no longer counts toward current compliance status.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2019-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2013-10-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2013-07-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2013-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Average · code 02 | Arseniccode 1005 | Yes | Resolved |
| 2007-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nitritecode 1041 | No | Resolved |
| 1984-08-01 | Public notice, recordkeeping or otherNotification, Public · code 06 | Not reported | No | Archived |
All 6 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.
Cinnabar Elementary School: frequently asked questions
Who runs Cinnabar Elementary School?
Cinnabar Elementary School (PWSID CA4900716) is a non-transient non-community water system owned by a local government. It is regulated by the CA state drinking water program.
How many people does Cinnabar Elementary School serve?
Cinnabar Elementary School reports serving 228 people through 2 service connections in Sonoma County, California.
Where does Cinnabar Elementary School 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 Cinnabar Elementary School have any drinking water violations?
EPA's records list 6 violations for this system; 4 are health-based, and the most recent began in July 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 Cinnabar Elementary School'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 6 violations for this system; 4 are health-based, and the most recent began in July 2019. For current results, consult EPA ECHO, or the CA state drinking water program.
Where can I find Cinnabar Elementary School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Cinnabar Elementary School 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 Sonoma County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Santa Rosa, City of | Sonoma | 175,396 | Community | Groundwater |
| Petaluma, City of | Sonoma | 60,781 | Community | Groundwater |
| Rohnert Park, City of | Sonoma | 43,821 | Community | Groundwater |
| Windsor, Town of | Sonoma | 25,561 | Community | Groundwater |
| Valley of the Moon Water District | Sonoma | 23,107 | Community | Groundwater |
| Sonoma, City of | Sonoma | 11,725 | 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, “Cinnabar Elementary School, PWSID CA4900716, California”, https://aquacensus.com/water-systems/california/cinnabar-elementary-school-ca4900716 (data as of October 1, 2026).