Public water system · CA4901275
ActiveCornerstone Sonoma
Transient non-community water system in Sonoma County, California, drawing primarily on groundwater.
Dataset updated . Source: EPA SDWIS/ECHO public records.
Population served
175
Service connections
6
Primary source
GW
Groundwater
System type
TNCWS
Transient non-community water system
System record
Violations & enforcement
| Began | Violation | Contaminant or rule | Health-based | Status |
|---|---|---|---|---|
| 2017-11-01 | Monitoring and reportingMonitoring of Treatment (SWTR-Unfilt/GWR) · code 31 | Groundwater Rulecode 0700 | No | Resolved |
| 2016-10-01 | MonitoringMonitoring, Routine (RTCR) · code 3A | Revised Total Coliform Rulecode 8000 | No | Resolved |
| 2012-01-01 | Contaminant level above the legal limitMaximum Contaminant Level Violation, Monthly (TCR) · code 22 | Total coliform bacteria (TCR)code 3100 | Yes | 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.
Cornerstone Sonoma: frequently asked questions
Is Cornerstone Sonoma's water safe to drink?
Cornerstone Sonoma is an active transient non-community water system regulated under the Safe Drinking Water Act, overseen by the CA state drinking water program. EPA's SDWA data records violations for this system — the most recent are listed on this page, including health-based violations; consult EPA ECHO or your annual Consumer Confidence Report for its current compliance status.
Who runs Cornerstone Sonoma?
Cornerstone Sonoma (PWSID CA4901275) is a private-owned transient non-community water system, regulated by the CA state drinking water program.
How many people does Cornerstone Sonoma serve?
Cornerstone Sonoma reports serving 175 people through 6 service connections in Sonoma County, California.
Where does Cornerstone Sonoma get its water?
EPA SDWIS lists this system's primary water source as groundwater.
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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