Santa Ana Region - Regional Boundaries Map
Map of Santa Ana Region
The cities and municipalities that fall within the jurisdiction of the Santa Ana Regional Water Quality Control Board are listed by county below.
Cities Within Orange County
| Anaheim | Foothill Ranch | Newport Beach |
| Anaheim Hills | Fullerton | Orange |
| Balboa/Balboa Island | Garden Grove | Placentia |
| Brea | Huntington Beach | Santa Ana |
| Buena Park | Irvine | Seal Beach |
| Corona Del Mar | La Habra | Stanton |
| Costa Mesa | La Palma | Sunset Beach |
| Cypress | Laguna Hills | Tustin |
| El Sobrante | Lake Forest | Villa Park |
| El Toro | Los Alamitos | Westminister |
| Fountain Valley | Midway City | Yorba Linda |
Cities Within Riverside County
| Beaumont | Idyllwild | Pedley |
| Calimesa | Lake Elsinore | Perris |
| Corona | Lakeview | Riverside |
| Edgemont | Menifee | Romoland |
| Glen Avon | Mira Loma | Rubidoux |
| Glen Ivy | Moreno Valley | San Jacinto |
| Hemet | Norco | Sun City |
Cities Within San Bernardino County
| Barton Flats | Fawnskin | Ontario |
| Big Bear City | Fontana | Rancho Cucamonga |
| Big Bear Lake | Forest Falls | Redlands |
| Bloomington | Glen Helen | Rialto |
| Chino | Highland | Rim Forest |
| Chino Hills | Loma Linda | Running Springs |
| Colton | Lytle Creek | San Bernardino |
| Crafton Hills | Mentone | Upland |
| Crestline | Mill Creek | Yucaipa |
| Devore | Montclair |
