| County | Region |
|---|---|
| Alameda | Region 5 |
| Alpine | Region 4 |
| Amador | Region 4 |
| Angeles National Forest | Region 9 |
| Butte | Region 2 |
| Calaveras | Region 4 |
| Colusa | Region 3 |
| Contra Costa | Region 5 |
| Del Norte | Region 13 |
| El Dorado | Region 3 |
| Fresno | Region 15 |
| Glenn | Region 2 |
| Humboldt | Region 13 |
| Imperial | Region 8 |
| Inyo | Region 16 |
| Kern | Region 17 |
| Kings | Region 17 |
| Lake | Region 1 |
| Lassen | Region 18 |
| Los Angeles | Region 7 |
| Madera | Region 15 |
| Marin | Region 1 |
| Mariposa | Region 4 |
| Mendocino | Region 1 |
| Merced | Region 4 |
| Modoc | Region 18 |
| Mono | Region 4 |
| Monterey | Region 6 |
| Napa | Region 1 |
| Nevada | Region 3 |
| Orange | Region 12 |
| Placer | Region 3 |
| Plumas | Region 2 |
| Riverside | Region 11 |
| Sacramento | Region 3 |
| San Benito | Region 6 |
| San Bernardino | Region 14 |
| San Diego | Region 8 |
| San Francisco | Region 6 |
| San Joaquin | Region 4 |
| San Luis Obispo | Region 19 |
| San Mateo | Region 6 |
| Santa Barbara | Region 19 |
| Santa Clara | Region 6 |
| Santa Cruz | Region 6 |
| Shasta | Region 18 |
| Sierra | Region 3 |
| Siskiyou | Region 18 |
| Solano | Region 1 |
| Sonoma | Region 1 |
| Stanislaus | Region 4 |
| Sutter | Region 3 |
| Tehama | Region 2 |
| Trinity | Region 18 |
| Tulare | Region 17 |
| Tuolumne | Region 4 |
| Ventura | Region 9 |
| Yolo | Region 3 |
| Yuba | Region 3 |
- Region 1…Serving: Mendocino, Lake, Sonoma, Napa, Solano, and Marin Counties
- Region 2..Serving: Tehama, Plumas, Glenn, and Butte Counties
- Region 3…Serving: Sutter, Placer, Yolo, Sacramento, Colusa, El Dorado, Sierra, Yuba, and Nevada Counties
- Region 4…Serving: Stanislaus, San Joaquin, Merced, Mono, Alpine, Amador, Calaveras, Mariposa and Tuolumne Counties
- Region 5…Serving: Alameda and Contra Costa Counties.
- Region 6…Serving: San Francisco, San Mateo, Santa Clara, and part of Santa Cruz Counties.
- Region 7…Serving: Los Angeles County
- Region 8…Serving: San Diego and Imperial Counties
- Region 9…Serving: Ventura County and Angeles National Forest – Currently Inactive
- Region 10..Serving: Monterey, San Benito, and parts of Santa Cruz – Currently Inactive
- Region 11..Serving: Riverside County
- Region 12..Serving: Orange County
- Region 13..Serving: Del Norte and Humboldt Counties
- Region 14..Serving: San Bernardino Counties
- Region 15…Serving: Fresno and Madera Counties
- Region 16…Serving: Inyo County
- Region 17…Serving: Kern, Kings and Tulare Counties
- Region 18…Serving: Shasta, Siskiyou, Modoc, Trinity and Lassen Counties.
- Region 19…Serving: San Luis Obispo and Santa Barbara Counties – Currently Inactive
