Formed on July 10, 1952, the Walnut Valley Water District, a California Water District, is located approximately 20 miles east of Los Angeles in the San Gabriel Valley, encompassing an area of approximately 29 square miles with over 27,000 service connections serving more than 100,000 multi-use customers in six communities. The District’s present service area includes all of the city of Diamond Bar, portions of the cities of Industry, Pomona, Walnut, and West Covina, and the easterly section of the unincorporated area of Rowland Heights.
Statistics
| Population in Service Area | 99,956 | |
| Total Acreage in Service Area | 17,900 | |
| Number of Active Water Services | 27,459 | |
| Number of Reservoirs | 32 | |
| Number of Booster Pump Stations | 17 | |
| Total Gallons of Water Storage | 95.8 million | |
| Number of Pressure Regulating Stations | 23 | |
| Total Distance of Water Mains in System (Miles) | 434 | |
| Water Quality Analyses Performed Yearly | 17,000 | |
| Average Annual Water Deliveries (Gallons) | 5.5 billion | |
| Average Water System Daily Use (Gallons) | 15 million | |
| Average Daily Use Per Person (Gallons) | 150 | |
| Annual Water Shut-Offs | 188 | |