CA4910012 · California

SONOMA, CITY OF

Federal fiscal 2026Q3 · EPA violation and follow-up records

Violation records shown: 5
EPA health-based flag: 0
Health-based records unresolved in this snapshot: 0
Monitoring and reporting records: 5

Counties listed by EPA · Sonoma County, California

Find the utility’s annual water quality report. For current advisories, check the utility or local drinking-water authority.

Violations and what followed

Among 4 resolved records with both dates, the median interval from recorded noncompliance start to EPA’s return-to-compliance date was 227.5 days. The interval uses the reporting periods and dates on file.

Monitoring or reporting · Unaddressed by formal action
Notification, Known or Potential LSLViolation 1018009 · LEAD AND COPPER RULE REVISIONS · Lead and Copper Rule Revisions
Noncompliance period start July 2, 2025 · first reported November 17, 2025
No linked action row appears in the records shown.

Monitoring or reporting · Resolved

Monitoring, RegularViolation 1018008 · Arsenic · Arsenic Rule

Noncompliance period start April 1, 2021 · period end June 30, 2021 · first reported November 15, 2021 · EPA return-to-compliance field June 30, 2021

2 linked actions

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1018011	September 8, 2021	Formal	State Administrative/Compliance Order without penalty issued
1018012	September 19, 2024	Resolving	State Compliance achieved

Monitoring or reporting · Resolved

Monitoring, Routine (IDSE)Violation 1018006 · TTHM · Stage 2 Disinfectants and Disinfection Byproducts Rule

Noncompliance period start January 1, 2020 · period end December 31, 2020 · first reported March 31, 2021 · EPA return-to-compliance field December 31, 2020

2 linked actions

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1018009	March 24, 2021	Formal	State Administrative/Compliance Order without penalty issued
1018014	September 19, 2024	Resolving	State Compliance achieved

Monitoring or reporting · Resolved

Monitoring, Routine (IDSE)Violation 1018005 · Total Haloacetic Acids (HAA5) · Stage 2 Disinfectants and Disinfection Byproducts Rule

Noncompliance period start January 1, 2020 · period end December 31, 2020 · first reported March 31, 2021 · EPA return-to-compliance field December 31, 2020

2 linked actions

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1018009	March 24, 2021	Formal	State Administrative/Compliance Order without penalty issued
1018014	September 19, 2024	Resolving	State Compliance achieved

Monitoring or reporting · Resolved

Monitoring, Routine (RTCR)Violation 1018007 · Revised Total Coliform Rule · Revised Total Coliform Rule

Noncompliance period start November 1, 2017 · period end November 30, 2017 · first reported March 31, 2021 · EPA return-to-compliance field November 30, 2017

2 linked actions

Enforcement and resolution records linked by EPA
Action ID	Date	Category	EPA action type
1018010	March 24, 2021	Informal	State Formal Notice of Violation issued
1018013	September 19, 2024	Resolving	State Compliance achieved

EPA data and scope

How to read the records

The enforcement snapshot is federal fiscal 2026Q3. The EPA archive labels its violation file October 13, 2026. EPA says federal reporting can lag by several months. For current advisories, check your utility or local drinking-water authority.

We matched active community water systems by public water system ID between EPA’s system search and SDWIS inventory. We show violations with a recorded noncompliance, initial reporting or return-to-compliance date from 2021 onward, plus earlier records listed as Addressed or Unaddressed.
EPA’s health-based flag identifies violations of contaminant or disinfectant limits or treatment requirements. Monitoring and reporting violations describe required tests or reports. Neither category measures household exposure.
Addressed means EPA records formal enforcement on a violation that remains unresolved in the snapshot. Unaddressed means no formal action is recorded for an unresolved violation. Resolved can mean compliance was restored, the rule ceased to apply, or further action was unnecessary. Archived is a separate status.
We count a violation once per water system and group its distinct linked actions. Conflicting records are set aside. Places are EPA-listed search locations and can include mailing locations. Use the provider name and system ID to identify your service.

EPA data dictionary and files · EPA reporting and enforcement FAQ · Find an annual water quality report · How to get the report from your utility