TWIN HILLS SCHOOL DIST-TWIN HILLS SCHOOL
California - Non-Transient Non-Community - PWSID: CA4900707
System Information
| PWSID | CA4900707 |
| System Name | TWIN HILLS SCHOOL DIST-TWIN HILLS SCHOOL |
| System Type | Non-Transient Non-Community |
| Water Source | Ground Water |
| Activity Status | Active |
| Owner Type | Local |
| EPA Region | 09 |
| Serves School | Yes |
| Wholesaler | No |
| First Reported | Mar 22, 1979 |
| Last Reported | Mar 20, 2026 |
Location & Contact
| State | California |
| City | SEBASTOPOL |
| ZIP Code | 95472 |
| Address | 700 Watertrough Road |
| Organization | PEDERSEN, DANA |
| Phone | 707-823-0871 |
Population & Service
| Population Served | 400 |
| Service Connections | 2 |
Drinking Water Violations (8)
This water system has 8 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Sep 1, 2008 | Sep 30, 2008 | MR | No | No | - | 5% of samples | - | Resolved | Sep 30, 2008 | - | |
| Sep 1, 2008 | Sep 30, 2008 | MR | No | No | - | 5% of samples | - | Resolved | Sep 30, 2008 | - | |
| Jan 1, 2006 | Dec 31, 2006 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2006 | - | |
| Jan 1, 2006 | Dec 31, 2006 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2006 | - | |
| Jan 1, 2005 | Dec 31, 2005 | MR | No | Yes | - | 0.060 mg/L | - | Resolved | Dec 31, 2005 | - | |
| Jan 1, 2005 | Dec 31, 2005 | MR | No | Yes | - | 0.080 mg/L | - | Resolved | Dec 31, 2005 | - | |
| Jul 1, 1993 | Mar 1, 2000 | MR | No | No | - | TT | - | Resolved | Mar 1, 2000 | - | |
| Aug 1, 1984 | Aug 31, 1984 | Other | No | No | - | - | - | Archived | Aug 31, 1984 | - |
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.