Santa Fe Dam

This article is about the dam in California. For the dam in Catalonia, see Santa Fe Reservoir.
Santa Fe Dam

Satellite view of four of the five major dams on the San Gabriel River system. Santa Fe Dam is the large structure on the bottom left (southwest).
Country United States
Location Azusa, California
Coordinates 34°06′57″N 117°58′21″W / 34.11583°N 117.97250°WCoordinates: 34°06′57″N 117°58′21″W / 34.11583°N 117.97250°W[1]
Construction began 1941
Opening date 1949
Owner(s) U.S. Army Corps of Engineers
Dam and spillways
Type of dam Earthfill
Impounds San Gabriel River
Height 92 ft (28 m)
Length 23,800 ft (7,300 m)
Dam volume 12,033,000 cu yd (9,200,000 m3)
Spillway type Uncontrolled overflow
Spillway capacity 200,000 cu ft/s (5,700 m3/s)
Reservoir
Creates Santa Fe Flood Control Basin
Total capacity 45,409 acre·ft (56,011,000 m3)
Catchment area 236 sq mi (610 km2)
Surface area 1,000 acres (400 ha)
Power station
Hydraulic head 87 ft (27 m)

Santa Fe Dam is a flood-control dam on the San Gabriel River located a few miles southwest of Azusa in Los Angeles County, California. For most of the year, the 92-foot (28 m)-high dam and its reservoir lie empty, but can hold more than 45,000 acre feet (56,000,000 m3) of water during major storms. During the dry season, the basin behind the dam is used for groundwater recharge, as well as various recreational activities.

History

Construction of the dam began in 1941 under the U.S. Army Corps of Engineers (USACE), mainly in response to major floods on the river in 1938; however, work stopped in 1943 and did not resume again until 1946 due to the unlucky intervention of a major flood and World War II. The dam embankment and spillway were completed in early 1947, and the entire project was finished in January 1949 with the installation of the spillway gates, four months ahead of schedule.[2]

Statistics

Santa Fe Dam is a horseshoe-shaped curved gravity structure located on the alluvial flood plain of the San Gabriel River roughly 3 mi (4.8 km) downstream from the San Gabriel Mountains. The dam is of zoned earthen construction and has a structural height of 92 feet (28 m), standing 87 feet (27 m) above the riverbed. It is one of the largest dams by volume in the United States, containing more than 12,000,000 cubic yards (9,200,000 m3) of material in an embankment more than four miles long.[3]

The reservoir formed behind Santa Fe has a maximum capacity of 45,409 acre·ft (56,011,000 m3) at spillway crest, 21 feet (6.4 m) below the top of the dam itself. Water releases from the dam are controlled by two sets of gates. The outlet works, located at the base of the dam, are fed by sixteen 7 ft (2.1 m) diameter conduits capable of discharging 17,000 cu ft/s (480 m3/s). The emergency spillway is located to the northwest of the dam and comprises a concrete overflow weir with a capacity of 200,000 cu ft/s (5,700 m3/s).[4]

Operations

The dam functions as a dry dam, with its reservoir empty most of the year. During large floods, water is stored behind the dam and then released as quickly as possible without exceeding the capacity of downstream levees. Releases from Santa Fe are coordinated with Whittier Narrows Dam 10 miles (16 km) downstream, as well as the upstream Cogswell, San Gabriel and Morris Dams, to provide flood protection to cities along the San Gabriel River. By capacity, it is the second largest dam along the San Gabriel, after Whittier Narrows.[3][5][6]

During the summer and autumn months, most of the water flowing into the Santa Fe reservoir is diverted into the Santa Fe Spreading Grounds, located near the upper end of the flood control basin, helping to recharge groundwater levels in the San Gabriel Valley. Excess inflow can be sent to the Peck Road Water Conservation Area and additional spreading grounds along the Rio Hondo. As a result, the San Gabriel River channel below the dam is often bone dry.[7] Most of the spreading grounds are owned and maintained by the Los Angeles County Department of Public Works, reclaiming an average of 110,000 acre·ft (140,000,000 m3) of water each year.[5]

Recreation

During most of the year, the empty reservoir behind the Santa Fe Dam is used for recreational purposes. The Santa Fe Dam Recreation Area is an 836-acre (338 ha) multi-use facility located behind the dam. The park's mainstay is a 70-acre (28 ha) lake with boat rentals, fishing, and a swimming beach, as well as hiking trails and plant conservation areas.[8]

See also

References

  1. "Santa Fe Dam". Geographic Names Information System. United States Geological Survey. 1981-01-19. Retrieved 2011-11-25.
  2. "Hydrology". The Natural History of Santa Fe Dam Recreation Area. California Native Plant Society, San Gabriel Mountains Chapter. Retrieved 2011-11-25.
  3. 3.0 3.1 "Santa Fe Dam". National Performance of Dams Program. Stanford University. Retrieved 2011-11-25.
  4. Janes, Robert (December 1943). "The Santa Fe Dam" (PDF). Engineering and Science Monthly. pp. 4–18. Retrieved 2011-11-25.
  5. 5.0 5.1 "The San Gabriel River: Past and Present" (PDF). The San Gabriel River Corridor Master Plan. Los Angeles Department of Public Works. Retrieved 2011-11-25.
  6. "Earth Observatory". National Aeronautics and Space Administration. 2005-01-23. Retrieved 2011-11-25.
  7. "Flood Control and Water Conservation" (PDF). San Gabriel River Flood Control. CSU Fullerton. Retrieved 2011-11-25.
  8. "Santa Fe Dam Recreational Area". Parks and Recreation. County of Los Angeles. Retrieved 2011-11-25.