TERWILLIGER ASSOCIATION
California — Transient Non-Community — PWSID: CA3301146
System Information
| PWSID | CA3301146 |
| System Name | TERWILLIGER ASSOCIATION |
| System Type | Transient Non-Community |
| Water Source | Ground Water |
| Activity Status | Active |
| Owner Type | Private |
| EPA Region | 09 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Mar 22, 1979 |
| Last Reported | Mar 20, 2026 |
Location & Contact
| State | California |
| City | ANZA |
| ZIP Code | 92539 |
| Address | PO Box 390433 |
| Organization | ASHBY, ANNIE |
| Phone | 760-519-6062 |
Population & Service
| Population Served | 2,401 |
| Service Connections | 2 |
Drinking Water Violations (13)
This water system has 13 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Jan 1, 2021 | Mar 31, 2021 | MON | No | Yes | — | — | — | Resolved | Mar 31, 2021 | — | |
| Jan 1, 2021 | Mar 31, 2021 | MON | No | Yes | — | — | — | Resolved | Mar 31, 2021 | — | |
| Mar 1, 2016 | Apr 30, 2016 | MCL | Yes | No | — | 5% of samples | — | Resolved | Apr 30, 2016 | — | |
| Mar 1, 2016 | Apr 30, 2016 | MCL | Yes | No | — | 5% of samples | — | Resolved | Apr 30, 2016 | — | |
| Mar 1, 2016 | Apr 30, 2016 | MCL | Yes | No | — | 5% of samples | — | Resolved | Apr 30, 2016 | — | |
| Aug 1, 2015 | Aug 31, 2015 | MCL | Yes | No | — | 5% of samples | — | Resolved | Aug 31, 2015 | — | |
| Aug 1, 2015 | Aug 31, 2015 | MCL | Yes | No | — | 5% of samples | — | Resolved | Aug 31, 2015 | — | |
| Jan 1, 2014 | Dec 31, 2016 | MR | No | Yes | — | 1 mg/L | — | Resolved | Dec 31, 2016 | — | |
| Jan 1, 2014 | Dec 31, 2016 | MR | No | Yes | — | 1 mg/L | — | Resolved | Dec 31, 2016 | — | |
| Dec 1, 1983 | Dec 31, 1983 | Other | No | No | — | — | — | Archived | Dec 31, 1983 | — | |
| Mar 1, 1983 | Mar 31, 1983 | Other | No | No | — | — | — | Archived | Mar 31, 1983 | — | |
| Feb 1, 1983 | Feb 28, 1983 | Other | No | No | — | — | — | Archived | Feb 28, 1983 | — | |
| Jan 1, 1983 | Jan 31, 1983 | Other | No | No | — | — | — | Archived | Jan 31, 1983 | — |
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.