Hoover Dam is a concrete arch-gravity dam in the Black Canyon of the Colorado River, on the border between the U.S. states of Nevada and Arizona. It was constructed between 1931 and 1936 during the Great Depression and was dedicated on September 30, 1935, by President Franklin D. Roosevelt. Its construction was the result of a massive effort involving thousands of workers, and cost over one hundred lives. It was referred to as Hoover Dam after President Herbert Hoover in bills passed by Congress during its construction, but was named Boulder Dam by the Roosevelt administration. The Hoover Dam name was restored by Congress in 1947.
A dam is a barrier that stops or restricts the flow of surface water or underground streams. Reservoirs created by dams not only suppress floods but also provide water for activities such as irrigation, human consumption, industrial use, aquaculture, and navigability. Hydropower is often used in conjunction with dams to generate electricity. A dam can also be used to collect or store water which can be evenly distributed between locations. Dams generally serve the primary purpose of retaining water, while other structures such as floodgates or levees are used to manage or prevent water flow into specific land regions. The earliest known dam is the Jawa Dam in Jordan, dating to 3,000 BC.
A gravity dam is a dam constructed from concrete or stone masonry and designed to hold back water by using only the weight of the material and its resistance against the foundation to oppose the horizontal pressure of water pushing against it. Gravity dams are designed so that each section of the dam is stable and independent of any other dam section.
The Woronora Dam is a heritage-listed concrete gravity dam with an uncontrolled serpentine spillway across the Woronora River, located south of Greater Metropolitan Sydney, in the suburb of Woronora Dam, Sutherland Shire, New South Wales, Australia. The principal purpose of the dam is for potable water supply for Sydney's southern suburbs and the northern suburbs of the Illawarra region. The impounded 71,790-megalitre reservoir is also called Woronora Dam and is sometimes incorrectly called Lake Woronora. The dam was designed by G. E. Haskins, Chief Engineer and the Metropolitan Water, Sewerage and Drainage Board of NSW (MWS&DB) and built from 1927 to 1941 by the MWS&DB. The property is owned by the Sydney Catchment Authority, an agency of the Government of New South Wales. It was added to the New South Wales State Heritage Register on 18 November 1999.
Bandai-Asahi National Park is a national park in the Tōhoku region, Honshū, Japan. The park site straddles over Fukushima Prefecture, Yamagata Prefecture, and Niigata Prefecture. The park was designated as a national park on September 5, 1950. The park encompasses 186,404 ha of land, consisting of three independent units: the Dewasanzan-asahi Region, Iide Region, and Bandaiazuma-Inawashiro Region.
Roller-compacted concrete (RCC) or rolled concrete (rollcrete) is a special blend of concrete that has essentially the same ingredients as conventional concrete but in different ratios, and increasingly with partial substitution of fly ash for Portland cement. The partial substitution of fly ash for Portland Cement is an important aspect of RCC dam construction because the heat generated by fly ash hydration is significantly less than the heat generated by Portland Cement hydration. This in turn reduces the thermal loads on the dam and reduces the potential for thermal cracking to occur. RCC is a mix of cement/fly ash, water, sand, aggregate and common additives, but contains much less water. The produced mix is drier and essentially has no slump. RCC is placed in a manner similar to paving; the material is delivered by dump trucks or conveyors, spread by small bulldozers or specially modified asphalt pavers, and then compacted by vibratory rollers.
Aimata Dam (相俣ダム) is a dam built on the Akaya River, part of the class-A Tonegawa River system at Aimata in the city of Minami, in the Tone District of Gunma Prefecture, Japan.
The Iwamatsu Dam (岩松ダム) is a dam situated in Hokkaidō, Japan. Work began on the dam's construction in 1939. The construction was completed in 1941.
The Ikawa Dam is a dam on the Ōi River in Aoi-ku, Shizuoka, Shizuoka Prefecture on the island of Honshū, Japan. It was the first hollow core concrete gravity dam to be constructed in Japan, and has a hydroelectric power generating station owned by the Chubu Electric Power Company.
The Nagashima Dam is a dam on the Ōi River, located in Kawanehon Town, Haibara District, Shizuoka Prefecture on the island of Honshū, Japan.
The Miyagase Dam is a dam on the Nakatsu River, a main tributary of the Sagami River in Aikō District, Kanagawa Prefecture, Japan. It straddles the border between the village of Kiyokawa, town of Aikawa and the former town of Tsukui.
Gosho Dam is a multipurpose dam on the Shizukuishi River, a branch of the Kitakami River in Morioka, Iwate Prefecture, Japan, completed in 1981.
Yuda Dam (湯田ダム) is a multipurpose dam located in the town of Nishiwaga, Iwate, in the Tohoku region of northern Japan. Completed in 1964, it is managed by the Tohoku Regional Development Bureau of the Ministry of Land, Infrastructure and Transport. Located on the Waga River, a branch of the Kitakami River, it is the third largest of the dams built as part of the Kitakami Area Comprehensive Development Plan (KVA). The dam creates Lake Kinshu, a popular sightseeing spot.
Ōhashi Dam (大橋ダム) is a dam built on the Yoshino River in Agawa District, Kōchi Prefecture of Japan. This concrete dam 73.5m high. It is a hydroelectric dam of the Shikoku Electric Power Company. It supplies water to the company's hydroelectric plant, Ōhashi Power Station, which can produce up to 5,500kW. It is the lower reservoir for a pumped-storage hydroelectric plant. The upper reservoir being Inamura Dam. Water flowing between these two can produce up to 615MW. It is a public works which The Japan Society of Civil Engineers has recommended as a site of Public Works Heritage.
Naruko Dam is a concrete gravity-arch dam in the city of Ōsaki, Miyagi Prefecture, Japan, completed in 1958 by Kajima Corporation. The dam is located on the Eaigawa, the former main course of the Kitakami River.
The Okukubi Dam (億首ダム) is a trapezoidal cemented, sand and gravel (CSG) dam on the Okukubi River in Kin, Okinawa Prefecture, Japan. Construction began in 2009 and its reservoir was filled by 31 March 2013. It is the first trapezoidal CSG-type to be constructed as a main dam in the world. Its purpose is to provide flood control and water for municipal use along with the irrigation of 70 ha of land.
The Ōmachi Dam is a concrete gravity dam on the Takase River just west of Ōmachi in Nagano Prefecture, Japan. Construction of the dam began in 1975 and it was completed in 1985. The primary purpose of the dam is water supply and it also supports a 13 MW hydroelectric power station. It is owned by TEPCO.
The Unbong Dam, or Yunfeng Dam, is a concrete gravity dam on the Yalu River which borders China and North Korea. It is located 33 km (21 mi) northeast of Ji'an in Jilin Province, China and Chasŏng in Chagang Province, North Korea. The primary purpose of the dam is hydroelectric power generation and it supports a 400 MW power station. Construction of the dam had initially began in August 1942 but was halted in 1945 after the surrender of Japan ending World War II. In October 1959, construction on the dam recommenced and in September 1965, the first of the four 100 MW Francis turbine-generators was operational. The last generator was operational on 4 April 1967. The 113.75 m (373 ft) tall dam creates a reservoir with a storage capacity of 3,895,000,000 m3 (3,157,728 acre⋅ft). The dam's spillway is an overflow type with 21 floodgates and has a maximum discharge of 21,900 m3/s (773,391 cu ft/s). The dam is located before a bend in the river and its power station is located on the other side of a ridge that meets the dam's right abutment. Water is delivered to the power station via two tunnels, 775 m (2,543 ft) and 759 m (2,490 ft) long. Generators 1 and 3 deliver power to China while 2 and 4 deliver to North Korea.
Medlow Dam is a heritage-listed major gated concrete-walled arch dam across the Adams Creek in the Blue Mountains region, located at Beauchamp Road, Medlow Bath in the City of Blue Mountains local government area of New South Wales, Australia. The dam was designed and built in 1907 by the NSW Department of Public Works. The dam's purpose is primarily for the potable water supply of the upper Blue Mountains region. The impounded reservoir is called Medlow Bath Reservoir. The dam is also known as Medlow Bath Dam, Lake Medlow Dam, Adams Creek Dam and Medlow Bath Reservoir. The property is owned by Sydney Water, a state-owned corporation of the Government of New South Wales. The dam was added to the New South Wales State Heritage Register on 18 November 1999.
Nagai Dam is a concrete gravity dam located in Yamagata Prefecture in Japan. The dam is used for flood control, water supply and power generation. The catchment area of the dam is 101.2 km2. The dam impounds about 140 ha of land when full and can store 51000 thousand cubic meters of water. The construction of the dam was started on 1979 and completed in 2010.
