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40-801: In the 1920s, the Los Angeles County Flood Control District proposed to impound the San Gabriel River just below the confluence of the East and West forks with a 512-foot (156 m) high, 2,500-foot (760 m) long concrete arch dam to capture floods and provide water conservation . To be named the San Gabriel Forks Dam, the project was canceled by the State Engineer after having convened an inquiry to investigate problems which were occurring at San Gabriel Dam site, including

80-461: A landslide that destroyed a large portion of the construction site, in early November 1929. The inquiry panel concluded and issued a report to the State Engineer stating that the proposed dam "cannot be constructed without creating a menace to life and property." Subsequently, the design of the San Gabriel River flood control project was changed from one large dam to two smaller dams: San Gabriel No. 1 (San Gabriel Dam), about 2 miles (3.2 km) below

120-399: A maximum capacity of 45,409 acre⋅ft (56,011,000 m ) 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 m /s). The emergency spillway

160-733: A maximum of 4.95 MW and owned by the Department of Public Works. Water from the reservoir can be bypassed through a tunnel called the Azusa Conduit to another power plant downstream of Morris Dam. The power plant is located on the south side of the San Gabriel River directly below the mouth of San Gabriel Canyon. The original power plant was first built in 1898, by the San Gabriel Electric Company, and during its first few decades of operation powered electric railway lines in Los Angeles. At

200-479: A radius of 35 m (115 ft). Their second dam was built around 1350 and is called the Kurit Dam . After 4 m (13 ft) was added to the dam in 1850, it became 64 m (210 ft) tall and remained the tallest dam in the world until the early 20th century. The Kurit Dam was of masonry design and built in a very narrow canyon. The canyon was so narrow that its crest length is only 44% of its height. The dam

240-594: Is double-curved in both its horizontal and vertical planes may be called a dome dam . Arch dams with more than one contiguous arch or plane are described as multiple-arch dams . Early examples include the Roman Esparragalejo Dam with later examples such as the Daniel-Johnson Dam (1968) and Itaipu Dam (1982). However, as a result of the failure of the Gleno Dam shortly after it was constructed in 1923,

280-508: Is 17% less than the original capacity of 53,344 acre⋅ft (65,799,000 m) when the dam was first built, because sedimentation has reduced the water volume. Interest in sediment removal began in the 1980s, after several major wildfires in the San Gabriel Mountains and subsequent flooding caused millions of cubic yards of sediment to wash into the reservoir. The reservoir was dewatered in 2004 to allow for sediment removal, but work

320-495: Is 214 meters (702 ft) high and 1,314 meters (4,311 ft) long across its crest. It was completed in 1968 and put in service in 1970. Pensacola Dam was one of the last multiple arch types built in the United States. Its NRHP application states that this was because three dams of this type failed: (1) Gem Lake Dam, St. Francis Dam (California), Lake Hodges Dam (California). None of these failures were inherently caused by

360-481: 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 m /s). 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

400-403: Is made of concrete and placed in a V-shaped valley. The foundation or abutments for an arch dam must be very stable and proportionate to the concrete. There are two basic designs for an arch dam: constant-radius dams , which have constant radius of curvature, and variable-radius dams , which have both upstream and downstream curves that systematically decrease in radius below the crest. A dam that

440-545: Is still erect, even though part of its lower downstream face fell off. The Tibi Dam in Tibi , Spain was a post-medieval arch dam built between 1579 and 1594 and the first in Europe since the Romans. The dam was 42.7 metres (140 ft) high and 65 metres (213 ft) long. This arch dam rests on the mountains sides. In the early 20th century, the world's first variable-radius arch dam

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480-502: Is used for recreational purposes. The Santa Fe Dam Recreation Area , located in Irwindale , is an 836-acre (338 ha) multi-use facility located behind the dam. The park's main feature is a 70-acre (28 ha) lake with boat rentals, fishing, a swimming beach, hiking trails, cycling trails, and California native plants and chaparral habitat conservation areas. Santa Fe Dam is a horseshoe-shaped curved gravity structure located on

520-478: The California Coastal Commission . Currently, most of the sediment is sold for building material or ends up as landfill, but these options are highly limited. Flood control releases are coordinated in conjunction with the other mountain dams, Morris and Cogswell; and with Santa Fe and Whittier Narrows Dams on the lower San Gabriel River. The dam supports two small hydroelectric plants producing

560-559: 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 m ) of material in an embankment more than four miles long. The reservoir formed behind Santa Fe has

600-575: The 143-meter double-curved Morrow Point Dam in Colorado, completed in 1968. By the late 20th century, arch dam design reached a relative uniformity in design around the world. Currently, the tallest arch dam in the world is the 305 metres (1,001 ft) Jingpin-I Dam in China , which was completed in 2013. The longest multiple arch with buttress dam in the world is the Daniel-Johnson Dam in Quebec , Canada . It

640-412: The 2001 action/war film Behind Enemy Lines and is set in southern Bosnia . The dam was also a location for the 1934 film Spitfire . Arch dam An arch dam is a concrete dam that is curved upstream in plan. The arch dam is designed so that the force of the water against it, known as hydrostatic pressure , presses against the arch, causing the arch to straighten slightly and strengthening

680-599: The San Gabriel Valley Protective Association, which has rights to all water flows above 97,700 acre-feet as well as all storage space in San Gabriel, Cogswell and Morris Dams. The large reservoir, known as San Gabriel Reservoir No. 1, is nearly 3 miles (4.8 km) long when full. The 525-acre (212 ha) reservoir stores 44,183 acre⋅ft (54,499,000 m) of water when full, creating one of Southern California's largest instream reservoirs. This

720-562: The base thickness to the structural height (b/h) as: Arch dams classified with respect to their structural height are: The development of arch dams throughout history began with the Romans in the 1st century BC and after several designs and techniques were developed, relative uniformity was achieved in the 20th century. The first known arch dam, the Glanum Dam , also known as the Vallon de Baume Dam,

760-470: The basin, but funds committed elsewhere precluded recreation development at the basin until 1974. A Master Plan was prepared by the corps in 1975. It described recreation amenities proposed to be cost shared equally between the corps and the county and to be maintained by the county. The majority of the existing recreation amenities in the basin were built between 1976 and 1984. The recreation amenities constructed during this time period were jointly developed by

800-675: The construction of new multiple arch dams has become less popular. Contraction joints are normally placed every 20 m in the arch dam and are later filled with grout after the control cools and cures. Santa Fe Dam Santa Fe Dam is a flood-control dam on the San Gabriel River located in Irwindale in Los Angeles County , California , United States. 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 m ) of water during major storms. During

840-514: The corps and county on a cost shared basis. The original lease with the county was signed in May 1976 with a term of 50 years. In 1984 at the completion of the recreation amenities, the lease was amended to extend through December 2036. A master plan update in 1995 reflected 1995 conditions and proposed additional recreation development. During most of the year, the empty reservoir behind the Santa Fe Dam

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880-415: The dam has a clear span of 60 ft (18 m) and each buttress is 24 ft (7.3 m) wide. Arch dam designs would continue to test new limits and designs such as the double- and multiple-curve. Alfred Stucky and the U.S. Bureau of Reclamation developed a method of weight and stress distribution in the 1960s, and arch dam construction in the United States would see its last surge then with dams like

920-399: The dam was finished, Southern California was hit by record floods . The heaviest rains fell in the San Gabriel Mountains, swelling the San Gabriel River; on the night of March 2–3, 1938 a flood of 150,000 cu ft/s (4,200 m/s) poured out of the mountains and into San Gabriel Reservoir. San Gabriel Dam was able to knock about 40,000 cu ft/s (1,100 m/s) off the peak of

960-477: The dry months to spreading grounds at San Gabriel Canyon (Azusa) and Peck Basin (near Arcadia ), where it percolates into the local groundwater basin. Dam operations are coordinated by the San Gabriel River Water Committee (Committee of Nine), established in 1889 to represent water-rights holders on the San Gabriel River and with rights to 97,700 acre-feet (120,500 dam) of river water; and

1000-470: The dry season, the basin behind the dam is used for groundwater recharge , as well as various recreational activities. 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

1040-511: The entire project was finished in January 1949 with the installation of the spillway gates, four months ahead of schedule. The primary mission of the dam was to serve as a flood risk management tool to the communities along the San Gabriel River downstream of the Basin. The Los Angeles County Board of Supervisors passed a resolution in 1955 stating that the county wished to develop recreation amenities in

1080-417: The flood. Further downstream, Morris Reservoir was able to absorb roughly 30,000 cu ft/s (850 m/s), reducing the flood to less than half of what it would have been if not for the dams. Water stored behind San Gabriel Dam is an important source for groundwater recharge during the dry season of April through October. Water from San Gabriel, Cogswell and Morris Dams is released gradually through

1120-401: The multiple arch design. The design of an arch dam is a very complex process. It starts with an initial dam layout, that is continually improved until the design objectives are achieved within the design criteria. The main loads for which an arch dam is designed are: Other miscellaneous loads that affect a dam include: ice and silt loads, and uplift pressure. Most often, the arch dam

1160-591: The original Forks site, and San Gabriel No. 2 ( Cogswell Dam ), on the West Fork about 15 miles (24 km) above the confluence. The cost of San Gabriel No. 1 was greatly understated, creating a scandal; in context with the Great Depression , the Los Angeles Times observed that "it is not now necessary to gamble $ 26 million on a [troubled and wasteful agency]". The bond measure necessary for financing of

1200-417: The project was defeated by a narrow margin of 52 to 48 percent. As a result, the city turned to the federal Public Works Administration for money to complete the project. The San Gabriel No. 1 dam was to be made of rock-fill, which provides greater seismic stability. Construction of the 315-foot (96 m) high San Gabriel Dam at this site began in 1932 and was completed in 1939. In early 1938, before

1240-459: The state of Oklahoma in 1940, was considered the longest multiple arch dam in the United States. Designed by W. R. Holway , it has 51 arches. and a maximum height of 150 ft (46 m) above the river bed. The total length of the dam and its sections is 6,565 ft (2,001 m) while the multiple-arch section is 4,284 ft (1,306 m) long and its combination with the spillway sections measure 5,145 ft (1,568 m). Each arch in

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1280-406: The structure as it pushes into its foundation or abutments. An arch dam is most suitable for narrow canyons or gorges with steep walls of stable rock to support the structure and stresses. Since they are thinner than any other dam type, they require much less construction material, making them economical and practical in remote areas. In general, arch dams are classified based on the ratio of

1320-468: The time, this 2000 kilowatt (KW) plant drew water directly from the San Gabriel River. In 1917, the plant was sold to Southern California Edison , before being incorporated into the Pasadena municipal electric system. The completion of San Gabriel Dam in 1939 ensured a steadier water supply for the power plant, and in the late 1940s a new 3000 KW facility was built to replace the old one. The dam appears in

1360-577: 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. 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

1400-598: The world, in particular by the U.S. Bureau of Reclamation . In 1920, the Swiss engineer and dam designer Alfred Stucky developed new calculation methods for arch dams, introducing the concept of elasticity during the construction of the Montsalvens arch dam in Switzerland, thereby improving the dam profile in the vertical direction by using a parabolic arch shape instead of a circular arch shape. Pensacola Dam , completed in

1440-408: Was 5.7 metres (19 ft) high and 52 m long (171 ft), with a radius of 19 m (62 ft). The curved ends of the dam met with two winged walls that were later supported by two buttresses. The dam also contained two water outlets to drive mills downstream. The Dara Dam was another arch dam built by the Romans in which the historian Procopius would write of its design: "This barrier

1480-503: Was built by the Romans in France and it dates back to the 1st century BC. The dam was about 12 metres (39 ft) high and 18 metres (59 ft) in length. Its radius was about 14 m (46 ft), and it consisted of two masonry walls. The Romans built it to supply nearby Glanum with water. The Monte Novo Dam in Portugal was another early arch dam built by the Romans in 300 AD. It

1520-615: Was built on the Salmon Creek near Juneau , Alaska . The Salmon Creek Dam's upstream face bulged upstream, which relieved pressure on the stronger, curved lower arches near the abutments. The dam also had a larger toe, which off-set pressure on the upstream heel of the dam, which now curved more downstream. The technology and economical benefits of the Salmon Creek Dam allowed for larger and taller dam designs. The dam was, therefore, revolutionary, and similar designs were soon adopted around

1560-460: Was delayed after heavy rains during the winter of 2004–2005 refilled the reservoir. Disposal of the removed sediment has been a contentious issue. The 2005 sediment removal project stored about 6,100,000 cubic yards (4,700,000 m) of sediment in a nearby canyon, but this is now prohibited due to environmental and safety issues. Another option would have been to truck the sediment to local beaches for replenishment , but this has also been banned by

1600-455: Was not built in a straight line, but was bent into the shape of a crescent, so that the curve, by lying against the current of the river, might be able to offer still more resistance to the force of the stream." The Mongols also built arch dams in modern-day Iran. Their earliest was the Kebar Dam built around 1300, which was 26 m (85 ft) high and 55 m (180 ft) long, and had

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