HOWELL MOUNTAIN MUTUAL WATER COMPANY
California — Community Water System — PWSID: CA2810001
System Information
| PWSID | CA2810001 |
| System Name | HOWELL MOUNTAIN MUTUAL WATER COMPANY |
| System Type | Community Water System |
| Water Source | Surface 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 | ANGWIN |
| ZIP Code | 94508 |
| Address | PO Box 9 |
| Organization | HIERS, TANNER |
| Phone | 707-965-2205 |
Population & Service
| Population Served | 1,240 |
| Service Connections | 379 |
Drinking Water Violations (92)
This water system has 92 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, 2023 | Mar 31, 2023 | MCL | Yes | No | 82 UG/L | 0.080 mg/L | 80 | Resolved | Mar 31, 2023 | — | |
| Jan 1, 2023 | Mar 31, 2023 | MCL | Yes | No | 82 UG/L | 0.080 mg/L | 80 | Resolved | Mar 31, 2023 | — | |
| Apr 1, 2021 | Jun 30, 2021 | MCL | Yes | No | .083 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2021 | — | |
| Apr 1, 2021 | Jun 30, 2021 | MCL | Yes | No | .083 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2021 | — | |
| Oct 1, 2020 | — | MR | No | No | — | TT | — | Resolved | Sep 30, 2021 | — | |
| Oct 1, 2020 | — | MR | No | No | — | TT | — | Resolved | Sep 30, 2021 | — | |
| Oct 1, 2016 | Dec 31, 2016 | MCL | Yes | No | .0865 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2016 | — | |
| Oct 1, 2016 | Dec 31, 2016 | MCL | Yes | No | .0865 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2016 | — | |
| Jul 1, 2016 | Sep 30, 2016 | MCL | Yes | No | 81.75 UG/L | 0.080 mg/L | 80 | Resolved | Sep 30, 2016 | — | |
| Jul 1, 2016 | Sep 30, 2016 | MCL | Yes | No | 81.75 UG/L | 0.080 mg/L | 80 | Resolved | Sep 30, 2016 | — | |
| Jan 1, 2015 | Dec 31, 2015 | MR | No | Yes | — | 10 mg/L | — | Resolved | Dec 31, 2015 | — | |
| Jan 1, 2015 | Dec 31, 2015 | MR | No | Yes | — | 10 mg/L | — | Resolved | Dec 31, 2015 | — | |
| Jul 1, 2013 | Sep 30, 2013 | MCL | Yes | No | .086 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2013 | — | |
| Jul 1, 2013 | Sep 30, 2013 | MCL | Yes | No | .086 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2013 | — | |
| Apr 1, 2013 | Jun 30, 2013 | MCL | Yes | No | .089 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2013 | — | |
| Apr 1, 2013 | Jun 30, 2013 | MCL | Yes | No | .089 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2013 | — | |
| Apr 1, 2011 | Jun 30, 2011 | MCL | Yes | No | .0616 MG/L | 0.060 mg/L | .06 | Resolved | Jun 30, 2011 | — | |
| Apr 1, 2011 | Jun 30, 2011 | MCL | Yes | No | .0616 MG/L | 0.060 mg/L | .06 | Resolved | Jun 30, 2011 | — | |
| Jan 1, 2011 | Mar 31, 2011 | MCL | Yes | No | .0907 MG/L | 0.080 mg/L | .08 | Resolved | Mar 31, 2011 | — | |
| Jan 1, 2011 | Mar 31, 2011 | MCL | Yes | No | .0693 MG/L | 0.060 mg/L | .06 | Resolved | Mar 31, 2011 | — | |
| Jan 1, 2011 | Mar 31, 2011 | MCL | Yes | No | .0907 MG/L | 0.080 mg/L | .08 | Resolved | Mar 31, 2011 | — | |
| Jan 1, 2011 | Mar 31, 2011 | MCL | Yes | No | .0693 MG/L | 0.060 mg/L | .06 | Resolved | Mar 31, 2011 | — | |
| Oct 1, 2010 | Dec 31, 2010 | MCL | Yes | No | .0731 MG/L | 0.060 mg/L | .06 | Resolved | Dec 31, 2010 | — | |
| Oct 1, 2010 | Dec 31, 2010 | MCL | Yes | No | .0731 MG/L | 0.060 mg/L | .06 | Resolved | Dec 31, 2010 | — | |
| Oct 1, 2010 | Dec 31, 2010 | MCL | Yes | No | .0994 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2010 | — | |
| Oct 1, 2010 | Dec 31, 2010 | MCL | Yes | No | .0994 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MCL | Yes | No | .0755 MG/L | 0.060 mg/L | .06 | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MCL | Yes | No | .1044 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MCL | Yes | No | .1044 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2010 | — | |
| Jul 1, 2010 | Sep 30, 2010 | MCL | Yes | No | .0755 MG/L | 0.060 mg/L | .06 | Resolved | Sep 30, 2010 | — | |
| Apr 1, 2010 | Jun 30, 2010 | MCL | Yes | No | .099 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2010 | — | |
| Apr 1, 2010 | Jun 30, 2010 | MCL | Yes | No | .099 MG/L | 0.080 mg/L | .08 | Resolved | Jun 30, 2010 | — | |
| Apr 1, 2010 | Jun 30, 2010 | MCL | Yes | No | .065 MG/L | 0.060 mg/L | .06 | Resolved | Jun 30, 2010 | — | |
| Apr 1, 2010 | Jun 30, 2010 | MCL | Yes | No | .065 MG/L | 0.060 mg/L | .06 | Resolved | Jun 30, 2010 | — | |
| Jan 1, 2010 | Mar 31, 2010 | MCL | Yes | No | .107 MG/L | 0.080 mg/L | .08 | Resolved | Mar 31, 2010 | — | |
| Jan 1, 2010 | Mar 31, 2010 | MCL | Yes | No | .107 MG/L | 0.080 mg/L | .08 | Resolved | Mar 31, 2010 | — | |
| Jan 1, 2010 | Mar 31, 2010 | MCL | Yes | No | .0816 MG/L | 0.060 mg/L | .06 | Resolved | Mar 31, 2010 | — | |
| Jan 1, 2010 | Mar 31, 2010 | MCL | Yes | No | .0816 MG/L | 0.060 mg/L | .06 | Resolved | Mar 31, 2010 | — | |
| Oct 1, 2009 | Dec 31, 2009 | MCL | Yes | No | .093 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2009 | — | |
| Oct 1, 2009 | Dec 31, 2009 | MCL | Yes | No | .093 MG/L | 0.080 mg/L | .08 | Resolved | Dec 31, 2009 | — | |
| Oct 1, 2009 | Dec 31, 2009 | MCL | Yes | No | .0706 MG/L | 0.060 mg/L | .06 | Resolved | Dec 31, 2009 | — | |
| Oct 1, 2009 | Dec 31, 2009 | MCL | Yes | No | .0706 MG/L | 0.060 mg/L | .06 | Resolved | Dec 31, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MCL | Yes | No | .0897 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MR | No | No | — | 0.060 mg/L | — | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MR | No | No | — | 0.080 mg/L | — | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MCL | Yes | No | .0639 MG/L | 0.060 mg/L | .06 | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MR | No | No | — | 0.060 mg/L | — | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MR | No | No | — | 0.080 mg/L | — | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MCL | Yes | No | .0639 MG/L | 0.060 mg/L | .06 | Resolved | Sep 30, 2009 | — | |
| Jul 1, 2009 | Sep 30, 2009 | MCL | Yes | No | .0897 MG/L | 0.080 mg/L | .08 | Resolved | Sep 30, 2009 | — |
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.