Type Reservoir Max. length 2 miles (3.2 km) Area 80 ha Length 3,219 m Surface elevation 145 m | Basin countries United States Surface area 197 acres (80 ha) Catchment area 174 km² Max width 457 m Water volume 7.586 million m³ | |
Location Diablo Range, eastern Santa Clara County, California Primary outflows North Fork Pacheco Creek | ||
Pacheco Reservoir is an artificial lake or reservoir in the Diablo Range in San Benito County, California, U.S.A. formed by a dam on the north fork of Pacheco Creek. Located north of State Route 152 in eastern Santa Clara County, the lake is about an hour's drive from downtown San Jose.
The lake is formed by a dam across the north fork of Pacheco Creek, whose waters reach Monterey Bay by way of the Pajaro River.
North Fork DamEdit
The lake's waters are impounded by the North Fork Dam, an earthen dam built in 1939. The dam is 100 feet (30 m) high and 600 feet (180 m) long and contains 325,000 cubic yards (248,000 m3) of material. Its crest is 483 feet (147 m) above mean sea level.
The reservoir dam is an impassable barrier to in-migrating steelhead trout (Oncorhynchus mykiss), preventing access to the nearly 34.5 miles (55.5 km) of stream consisting of North Fork Pacheco Creek, Mississippi Creek and East Fork Pacheco Creek. Resident rainbow (the landlocked form of steelhead) trout successfully rear in fast-water habitats above the dam. They grow rapidly and reach smolt size by the end of their first summer. In many years in late spring, prior to reservoir releases for agriculture, low stream flows and high water temperatures severely impact steelhead fry and small juveniles.