OAK KNOLLS MUTUAL WATER COMPANY
California - Community Water System - PWSID: CA1500465
System Information
| PWSID | CA1500465 |
| System Name | OAK KNOLLS MUTUAL WATER COMPANY |
| System Type | Community Water System |
| 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 | LAKE ISABELLA |
| ZIP Code | 93240 |
| Address | P.O. Box 3396 |
| Organization | TRUBEY, DENNIS |
| Phone | 928-234-0499 |
Population & Service
| Population Served | 123 |
| Service Connections | 47 |
Drinking Water Violations (41)
This water system has 41 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, 2025 | Mar 31, 2025 | MCL | Yes | No | 11 MG/L | 10 mg/L | - | Resolved | Mar 1, 2018 | - | |
| Oct 17, 2024 | - | RPT | No | No | - | - | - | Unaddressed | - | - | |
| Oct 17, 2024 | - | TT | Yes | No | - | - | - | Unaddressed | - | - | |
| Oct 1, 2024 | Dec 31, 2024 | MCL | Yes | No | 13 MG/L | 10 mg/L | - | Resolved | Mar 1, 2018 | - | |
| Oct 1, 2024 | Dec 31, 2024 | MCL | Yes | No | 13 MG/L | 10 mg/L | - | Resolved | Mar 1, 2018 | - | |
| Jul 1, 2024 | Sep 30, 2024 | MCL | Yes | No | 12 MG/L | 10 mg/L | - | Resolved | Mar 1, 2018 | - | |
| Jul 1, 2024 | Sep 30, 2024 | MCL | Yes | No | 12 MG/L | 10 mg/L | - | Resolved | Mar 1, 2018 | - | |
| Apr 1, 2024 | Jun 30, 2024 | MCL | Yes | No | 23 MG/L | 10 mg/L | - | Archived | Jun 30, 2024 | - | |
| Jan 1, 2024 | Mar 31, 2024 | MCL | Yes | No | 19 MG/L | 10 mg/L | - | Archived | Mar 31, 2024 | - | |
| Mar 1, 2012 | Mar 31, 2012 | MCL | Yes | No | - | 5% of samples | - | Resolved | Mar 31, 2012 | - | |
| Mar 1, 2012 | Mar 31, 2012 | MCL | Yes | No | - | 5% of samples | - | Resolved | Mar 31, 2012 | - | |
| Jul 1, 2008 | - | Other | No | No | - | - | - | Resolved | Aug 1, 2013 | - | |
| Jul 1, 2008 | - | Other | No | No | - | - | - | Resolved | Aug 1, 2013 | - | |
| Jul 1, 2007 | - | Other | No | No | - | - | - | Resolved | Aug 1, 2013 | - | |
| Jul 1, 2007 | - | Other | No | No | - | - | - | Resolved | Aug 1, 2013 | - | |
| Apr 1, 1998 | Apr 30, 1998 | MR | No | No | - | 5% of samples | - | Resolved | Apr 30, 1998 | - | |
| Apr 1, 1998 | Apr 30, 1998 | MR | No | No | - | 5% of samples | - | Resolved | Apr 30, 1998 | - | |
| Jan 1, 1997 | Dec 31, 2001 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2001 | - | |
| Jan 1, 1997 | Dec 31, 2001 | MR | No | Yes | - | 10 mg/L | - | Resolved | Dec 31, 2001 | - | |
| Jul 6, 1996 | - | MR | No | No | - | TT | - | Resolved | Mar 1, 2018 | - | |
| Jul 6, 1996 | - | MR | No | No | - | TT | - | Resolved | Mar 1, 2018 | - | |
| Jan 2, 1996 | - | MR | No | No | - | TT | - | Resolved | Mar 1, 2018 | - | |
| Jan 2, 1996 | - | MR | No | No | - | TT | - | Resolved | Mar 1, 2018 | - | |
| Feb 1, 1995 | Feb 28, 1995 | MR | No | No | - | 5% of samples | - | Resolved | Feb 28, 1995 | - | |
| Feb 1, 1995 | Feb 28, 1995 | MR | No | No | - | 5% of samples | - | Resolved | Feb 28, 1995 | - | |
| May 1, 1994 | May 31, 1994 | MR | No | No | - | 5% of samples | - | Resolved | May 31, 1994 | - | |
| May 1, 1994 | May 31, 1994 | MR | No | No | - | 5% of samples | - | Resolved | May 31, 1994 | - | |
| Mar 1, 1994 | Mar 31, 1994 | MR | No | No | - | 5% of samples | - | Resolved | Mar 31, 1994 | - | |
| Mar 1, 1994 | Mar 31, 1994 | MR | No | No | - | 5% of samples | - | Resolved | Mar 31, 1994 | - | |
| Jul 1, 1993 | Mar 1, 2000 | MR | No | No | - | TT | - | Resolved | Mar 1, 2000 | - | |
| Sep 1, 1984 | Sep 30, 1984 | Other | No | No | - | - | - | Archived | Sep 30, 1984 | - | |
| Aug 1, 1984 | Aug 31, 1984 | Other | No | No | - | - | - | Archived | Aug 31, 1984 | - | |
| Jul 1, 1984 | Jul 31, 1984 | Other | No | No | - | - | - | Archived | Jul 31, 1984 | - | |
| Jun 1, 1984 | Jun 30, 1984 | Other | No | No | - | - | - | Archived | Jun 30, 1984 | - | |
| May 1, 1984 | May 31, 1984 | Other | No | No | - | - | - | Archived | May 31, 1984 | - | |
| Mar 1, 1984 | Mar 31, 1984 | Other | No | No | - | - | - | Archived | Mar 31, 1984 | - | |
| Feb 1, 1984 | Feb 29, 1984 | Other | No | No | - | - | - | Archived | Feb 29, 1984 | - | |
| Oct 1, 1983 | Oct 31, 1983 | Other | No | No | - | - | - | Archived | Oct 31, 1983 | - | |
| Oct 1, 1981 | Sep 30, 1982 | MR | No | Yes | - | 15 pCi/L | - | Archived | Sep 30, 1982 | - | |
| Oct 30, 1980 | Oct 29, 1981 | MR | No | Yes | - | 15 pCi/L | - | Archived | Oct 29, 1981 | - | |
| - | - | - | No | No | - | - | - | - | - | - |
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.