RIO ALTO WATER DISTRICT
California — Community Water System — PWSID: CA5210005
System Information
| PWSID | CA5210005 |
| System Name | RIO ALTO WATER DISTRICT |
| System Type | Community Water System |
| Water Source | Ground Water |
| Activity Status | Active |
| Owner Type | Local |
| EPA Region | 09 |
| Serves School | No |
| Wholesaler | No |
| First Reported | Jan 25, 1983 |
| Last Reported | Nov 17, 2025 |
Location & Contact
| State | California |
| City | COTTONWOOD |
| ZIP Code | 96022 |
| Address | 22099 River View Drive |
| Organization | SLACK, MARTHA |
| Phone | 530-347-3835 |
Population & Service
| Population Served | 3,329 |
| Service Connections | 1,433 |
Drinking Water Violations (6)
This water system has 6 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 |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Apr 1, 2015 | Jun 30, 2015 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Jun 30, 2015 | Total Coliform Rule |
| Apr 1, 2015 | Jun 30, 2015 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Jun 30, 2015 | Total Coliform Rule |
| May 1, 2012 | May 31, 2012 | Coliform (TCR) | MR | No | No | — | 5% of samples | — | Resolved | May 31, 2012 | Total Coliform Rule |
| Nov 1, 2010 | Nov 30, 2010 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Nov 30, 2010 | Total Coliform Rule |
| Nov 1, 2010 | Nov 30, 2010 | Coliform (TCR) | MCL | Yes | No | — | 5% of samples | — | Resolved | Nov 30, 2010 | Total Coliform Rule |
| Jan 1, 2004 | Jan 31, 2004 | Coliform (TCR) | MR | No | No | — | 5% of samples | — | Resolved | Jan 31, 2004 | Total Coliform Rule |
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.