Public water system record
Estero Municipal Improvement District
Serves Foster City and San Mateo, San Mateo County, CA · 36,556 people served
Federal records show no health-based violations and 1 monitoring/reporting issue for Estero Municipal Improvement District in the last ten years.
System profile
- Health-based violations, last 10 years
- 0
- Resolved
- 0
- Unresolved
- 0
- Any acute record
- No
- Monitoring issues, last 10 years
- 1
Key facts
- Estero Municipal Improvement District buys its water from San Francisco Regional Water System.
- Most recent formal enforcement: compliance order (no penalty) by California, November 2007.
- Record on file since 1987, with 2 health-based violations before October 19, 2016.
- Lead pipe inventory: 0 lead and 0 unknown out of 8,213 service lines.
Check whether Estero Municipal Improvement District serves your address
Health-based violations
Since October 2016Violation data reflects EPA records through March 2026. For the most current status, visit the EPA ECHO database.
None since October 2016.
Monitoring and reporting issues
Since October 2016Missed tests or reports, not contaminants found above a limit.
| Issue | Start date | Status |
|---|---|---|
|
Total Trihalomethanes (TTHMs)
Monitoring and reporting
|
Jul 1, 2022 | Resolved |
Full record since 1987
EPA's records for Estero Municipal Improvement District go back to 1987. Before October 19, 2016 they list 2 health-based violations (2 resolved) and 2 monitoring or reporting violations.
| Violations that began in | Health-based | Monitoring and reporting |
|---|---|---|
| 1980s | 0 | 1 |
| 1990s | 1 | 1 |
| 2000s | 1 | 0 |
| 2020s | 0 | 1 |
Most recent health-based violation before October 19, 2016: Total Coliform, began October 2007, Resolved.
Show all 2 health-based violations before October 19, 2016
| Contaminant | Start date | Status |
|---|---|---|
|
Total Coliform
Contaminant limit exceeded
|
Oct 1, 2007 | Resolved |
|
Surface Water Treatment Rule
Treatment technique failure
|
Apr 1, 1992 | Resolved |
Enforcement actions
California regulators took 1 formal enforcement action against Estero Municipal Improvement District in 2007. The most recent was a compliance order (no penalty) in November 2007.
| Date | By | Action | Violations covered |
|---|---|---|---|
| Nov 19, 2007 | California | Compliance order (no penalty) | 1 violation (1 health-based): Total Coliform |
Where the water comes from
Estero Municipal Improvement District buys its water from San Francisco Regional Water System. It lists no wells or intakes of its own.
Buys water from
- San Francisco Regional Water System Burlingame, CA
Annual water quality report
Estero Municipal Improvement District must give its customers an annual water quality report (Consumer Confidence Report) by July 1, with the levels its tests found in the previous year.
Systems serving 10,000 or more people must mail or deliver the report to every customer, and from 2027 they must send it twice a year.
Find a posted report with EPA's Consumer Confidence Report search
Testing your own water
To test the water at your tap, or a private well this record does not cover, use a laboratory certified for drinking water by California.
Certified drinking water labs by state EPA guidance for private wells