FOSTER CITY, CA · San Mateo County
ESTERO MUNICIPAL IMPROVEMENT DISTRICT Water System
Consumer Confidence Report status
ESTERO MUNICIPAL IMPROVEMENT DISTRICT must publish a Consumer Confidence Report — the annual drinking water quality report covering calendar year 2026 — by July 1, 2027.
As of August 1, 2026, EPA's federal records show no open violations for ESTERO MUNICIPAL IMPROVEMENT DISTRICT.
Data sourced from the EPA ECHO database (SDWA bulk download), last refreshed August 1, 2026. This is a record-keeping and public-information tool — it does not replace California’s official records. Always confirm current status with California before making decisions based on this information.
System facts
- System ID (PWSID)
- CA4110021
- System type
- Community Water System
- Population served
- 36,556
- Service connections
- 8,035
- Ownership
- local government
- Water source
- surface water (rivers, lakes, or reservoirs)
ESTERO MUNICIPAL IMPROVEMENT DISTRICT is one of 376 community water systems in California in the 10,001 to 100,000 people size category, serving 36,556 people from surface water.
As of August 1, 2026, its federal record holds 3 entries between 1987 and 2022, all of which EPA lists as closed. Nothing has been added since 2022.
Of the 3, 1 are monitoring and reporting requirements — the category that accounts for about four in five of all violations in EPA's national dataset — rather than findings about the water itself. The record involves the Stage 2 Disinfectants and Disinfection Byproducts Rule, the Surface Water Treatment Rules, and the Miscellaneous Other Rules.
Violation history
Monitoring and Reporting (DBP)
—TTHM
July 1, 2022 – September 30, 2022
ResolvedTreatment Technique (SWTR and GWR)
Health-basedSurface Water Treatment Rule
April 1, 1992 – April 13, 1992
ResolvedNotification, Public
—No contaminant on record
August 1, 1987 – August 31, 1987
Archived
Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)
| Period | Violation | Contaminant / rule | Health-based | Status |
|---|---|---|---|---|
| July 1, 2022 – September 30, 2022 | Monitoring and Reporting (DBP) | TTHM | — | Resolved |
| April 1, 1992 – April 13, 1992 | Treatment Technique (SWTR and GWR) | Surface Water Treatment Rule | Health-based | Resolved |
| August 1, 1987 – August 31, 1987 | Notification, Public | — | — | Archived |
Resolved addressed and confirmed by the stateArchived closed in EPA's records (typically due to age or a data correction)
Enforcement actions
No enforcement actions on record for this system.
Common questions
Is ESTERO MUNICIPAL IMPROVEMENT DISTRICT required to publish a Consumer Confidence Report?
- Yes. ESTERO MUNICIPAL IMPROVEMENT DISTRICT is a community water system, and federal rules (40 CFR 141 Subpart O) require every community water system to publish a Consumer Confidence Report each year.
When is ESTERO MUNICIPAL IMPROVEMENT DISTRICT’s next Consumer Confidence Report due?
- ESTERO MUNICIPAL IMPROVEMENT DISTRICT’s next Consumer Confidence Report is due by July 1, 2027. The report covers calendar year 2026.
Does ESTERO MUNICIPAL IMPROVEMENT DISTRICT have any open drinking water violations on record?
- As of August 1, 2026, EPA's federal records show no open violations for ESTERO MUNICIPAL IMPROVEMENT DISTRICT.
What is a Consumer Confidence Report?
- A Consumer Confidence Report (CCR) is the annual drinking water quality report that community water systems must provide to the people they serve. It lists the contaminants detected in the system’s water during the year, where the water comes from, and how the results compare with federal limits. EPA’s revised CCR rule takes effect January 1, 2027, and the first reports in the new format are due July 1, 2027.
Contact
DANISH, ZAHEED
650-520-4620
FOSTER CITY, CA 94404