ESTERO MUNICIPAL IMPROVEMENT DISTRICT
California — Community Water System — PWSID: CA4110021
System Information
| PWSID | CA4110021 |
| System Name | ESTERO MUNICIPAL IMPROVEMENT DISTRICT |
| System Type | Community Water System |
| Water Source | Surface Water Purchased |
| Activity Status | Active |
| Owner Type | Local |
| EPA Region | 09 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Mar 22, 1979 |
| Last Reported | Nov 17, 2025 |
Location & Contact
| State | California |
| City | FOSTER CITY |
| ZIP Code | 94404 |
| Address | 100 Lincoln Centre Drive |
| Organization | DANISH, ZAHEED |
| Phone | 650-520-4620 |
Population & Service
| Population Served | 36,556 |
| Service Connections | 8,035 |
Drinking Water Violations (6)
This water system has 6 violations recorded in the EPA SDWIS database.
| Begin Date | End Date | Contaminant | Category | Health-Based | Major | Measured | Federal MCL | State MCL | Status | Return to Compliance | Rule |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Jul 1, 2022 | Sep 30, 2022 | TTHM | MR | No | No | — | 0.080 mg/L | — | Resolved | Sep 30, 2022 | Stage 2 Disinfectants and Disinfection Byproducts Rule |
| Jul 1, 2022 | Sep 30, 2022 | TTHM | MR | No | No | — | 0.080 mg/L | — | Resolved | Sep 30, 2022 | Stage 2 Disinfectants and Disinfection Byproducts Rule |
| Oct 1, 2007 | Oct 31, 2007 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Oct 31, 2007 | Total Coliform Rule |
| Oct 1, 2007 | Oct 31, 2007 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Oct 31, 2007 | Total Coliform Rule |
| Apr 1, 1992 | Apr 30, 1992 | Surface Water Treatment Rule | TT | Yes | No | — | — | — | Resolved | Apr 13, 1992 | Surface Water Treatment Rule |
| Aug 1, 1987 | Aug 31, 1987 | Other | No | No | — | — | — | Archived | Aug 31, 1987 | Miscellaneous Other Rules |
About This Water System
Public water system data comes from the EPA Safe Drinking Water Information System (SDWIS). Systems with violations must notify customers. Contact your water utility for the latest annual water quality report.