Public water system · MI2005413
ActiveSonoma Elementary School
At a glance
Sonoma Elementary School (PWSID MI2005413) is an active non-transient non-community water system in Calhoun County, Michigan. It reports serving 300 people through 1 service connection. Its primary water source is groundwater, and EPA lists it as privately owned. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2018.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
300
Service connections
1
Primary source
GW
Groundwater
System type
NTNCWS
Non-transient non-community water system
System record
How does Sonoma Elementary School compare with other water systems in Calhoun County?
By EPA's size categories, Sonoma Elementary School is a very small system (500 people or fewer). Calhoun County has 141 active public water systems. Its population served is about half of the county average of 666 people per system, and accounts for 0.3% of the 93,883 people reported by systems filed under the county. Across Michigan, the 10,599 active systems average 847 people each. Nationally, the average active non-transient non-community water system reports serving 430 people, so Sonoma Elementary School is about 30% 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. Michigan has 1,402 active non-transient non-community water systems, 13% of the state's 10,599 active systems. Groundwater means the system draws its water from wells or springs fed by underground aquifers. 10,214 Michigan systems (96%) list groundwater as their primary source.
Who owns and regulates Sonoma Elementary School?
EPA lists Sonoma Elementary School as privately owned. The MI state drinking water program is its primacy agency, the regulator with primary enforcement responsibility for the system under the Safe Drinking Water Act. 128 of the 141 active systems in Calhoun County (91%) are also privately owned.
Does Sonoma Elementary School have drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2018. The violations listed here began between January 2014 and April 2018. By type: 10 monitoring and reporting and 2 monitoring. The contaminant or rule involved most often is Revised Total Coliform Rule (2 of them). EPA lists 11 as resolved and 1 as unaddressed. 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. Unaddressed means the violation is not resolved or archived and is not yet covered by formal enforcement.
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2018-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-04-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2016-01-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Resolved |
| 2015-07-01 | Monitoring and reportingInitial Tap Sampling for Pb and Cu · code 51 | Lead and Copper Rulecode 5000 | No | Unaddressed |
| 2014-04-01 | Monitoring and reportingMonitoring, Regular · code 03 | Arseniccode 1005 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Thalliumcode 1085 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Seleniumcode 1045 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Cadmiumcode 1015 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Antimonycode 1074 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Mercurycode 1035 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Nickelcode 1036 | No | Resolved |
| 2014-01-01 | Monitoring and reportingMonitoring, Regular · code 03 | Berylliumcode 1075 | No | Resolved |
The 12 most recent 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.
Sonoma Elementary School: frequently asked questions
Who runs Sonoma Elementary School?
Sonoma Elementary School (PWSID MI2005413) is a non-transient non-community water system privately owned. It is regulated by the MI state drinking water program.
How many people does Sonoma Elementary School serve?
Sonoma Elementary School reports serving 300 people through 1 service connection in Calhoun County, Michigan.
Where does Sonoma 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 Sonoma Elementary School have any drinking water violations?
Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2018. 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 Sonoma 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. Of the 12 most recent violations in EPA's records, none is health-based, and the most recent began in April 2018. For current results, consult EPA ECHO, or the MI state drinking water program.
Where can I find Sonoma Elementary School's water quality report?
The annual Consumer Confidence Report requirement applies to community water systems. Sonoma 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 Calhoun County
| Water system | County | Population served | Type | Source |
|---|---|---|---|---|
| Battle Creek - Verona System | Calhoun | 43,975 | Community | Groundwater |
| Albion | Calhoun | 9,144 | Community | Groundwater |
| Marshall | Calhoun | 7,088 | Community | Groundwater |
| Pennfield Township | Calhoun | 3,916 | Community | Groundwater |
| Springfield | Calhoun | 3,833 | Community | Purchased groundwater |
| Emmett Township | Calhoun | 2,550 | Community | Purchased 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, “Sonoma Elementary School, PWSID MI2005413, Michigan”, https://aquacensus.com/water-systems/michigan/sonoma-elementary-school-mi2005413 (data as of October 1, 2026).