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23-590: Manton Dam is a small concrete arch dam on the Manton River, approximately 70 km (43 mi) south of Darwin, Northern Territory in Australia. The dam was originally constructed by the Department of Defence during World War II to provide a reliable supply of fresh water to Darwin, completed in 1942. The reservoir itself is now mostly used for recreation, such as fishing, boating and water skiing , surrounded by

46-549: A conservation area for native flora and fauna. The much larger Darwin River Dam was commissioned in 1972, with Manton Dam retained for emergency supply. Since then, PowerWater has maintained the dam and infrastructure in an inactive state. Since 1989, the Manton Dam Recreation Area has been open to the public within the portfolio of Parks & Wildlife Commission . Although camping and swimming are not permitted, it

69-479: 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

92-594: 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,

115-495: 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

138-514: Is a popular venue for recreational water sports. The reservoir is divided into three distinct zones, allowing separation between high speed watercraft like jet skis , an area for towing skiers and an area for kayaks, canoes, and sailing. The lake is also stocked with various fish species, with fishing permitted in all zones. The environment around the dam is an excellent habitat for crocodiles , which Parks and Wildlife regularly patrol and survey to trap and remove many of these animals, especially during

161-476: Is an early arch dam and was the first arch dam constructed by the Mongolians , around 1300 AD. It is the oldest surviving arch dam. The dam is 26m tall and 55m wide and was constructed for irrigation water supply. It was originally 24m tall but 2m of height was added in either the beginning or middle of the 17th century. The arch of the dam was of normal curvature with a radius of 35m and angle of 45-degrees. While

184-403: 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

207-545: 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

230-575: 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

253-434: The Romans in 300 AD. It 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

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276-599: The Vallon de Baume Dam, 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

299-532: 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. Kebar Dam The Kebar Dam is a masonry arch dam on the Kebar River, Iran , located near a town of the same name, 23 km southeast of Qom , near the village of Zanburak in Jannatabad, Qom . The dam

322-415: 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

345-444: The dam sat on limestone , its curve rested on two winged walls that served as abutments. The downstream face of the dam was vertical until near its abutment where it slightly curves out. Near the dam's right, or western, abutment there is a 10m deep cylindrical hole which served as an intake and outlet works for the dam. The outlet works is located at the bottom and is a larger opening but there are various smaller openings throughout

368-401: 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

391-453: The ratio of 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

414-459: 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

437-924: The wet season. In February 2014, an experimental hydroelectric generator was installed by the PowerWater in partnership with Charles Darwin University 's Centre for Renewable Energy. Outputting roughly 4kW, the small generator is connected to the mains power grid to take advantage of seasonal releases and spillages during the wet season, and is the first of its kind in the Territory. PowerWater's 2013 Darwin Region Water Supply Strategy outlines plans to reactivate Manton Dam to supply water in order to mitigate shortages before 2025, extracting up to 7,400 ML (1.6 × 10 ^  imp gal; 2.0 × 10 ^  US gal) per year to meet growing demand. In 2019, it

460-598: 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

483-615: 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

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506-476: Was estimated that associated works would cost $ 122 million. A 2018 report prepared by the CSIRO included a detailed investigation of potential dam sites to meet the future needs of the region. This report found that while Manton Dam could provide a short-term solution until a much larger storage can be created, there are some concerns over water quality. Arch dam In general, arch dams are classified based on

529-455: 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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