The or , is a high variable-radius

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 strengthe ...

on the Kurobe River in

Toyama Prefecture is a prefecture of Japan located in the Chūbu region of Honshu. Toyama Prefecture has a population of 1,044,588 (1 June 2019) and has a geographic area of 4,247.61 km2 (1,640.01 sq mi). Toyama Prefecture borders Ishikawa Prefecture to the ...

, Japan. The tallest dam in Japan, it supports the 335 MW Kurobe No. 4 Hydropower Plant and is owned by

Kansai Electric Power Company , also known as , is an electric utility with its operational area of Kansai region, Japan (including the Keihanshin megalopolis). The Kansai region is Japan's second-largest industrial area, and in normal times, its most nuclear-reliant. B ...

. It was constructed between 1956 and 1963 at a cost of ¥51.3 billion yen. The project was a difficult engineering feat for the rapidly growing post–World War II Japan, and claimed the lives of 171 people.

History

In 1951, the

was formed to provide electric power for the

Kansai region The or the , lies in the southern-central region of Japan's main island Honshū. The region includes the prefectures of Nara, Wakayama, Kyoto, Osaka, Hyōgo and Shiga, often also Mie, sometimes Fukui, Tokushima and Tottori. The metropoli ...

of Japan. Shortly after their formation, the area suffered from drought which caused power rationing. The drought along with the rapid growth of post–World War II Japan pushed the company to increase their generating capacity. After a series of geological and hydrological studies of the Kurobe River and Gorge, it was announced in late 1955 that the Kurobe Dam would be constructed. In July 1956, construction on the dam began. Problems quickly arose while transporting material to the construction site as only one small railway existed through the narrow gorge. Kansai decided to construct the Kanden Tunnel under Mount Akazawa that could bring supplies from Ōmachi eastward towards the construction site. The tunnel's construction proved an arduous task as a large fracture zone in the rock was encountered which took seven months to repair. In September 1959, the first

concrete Concrete is a composite material composed of fine and coarse aggregate bonded together with a fluid cement (cement paste) that hardens (cures) over time. Concrete is the second-most-used substance in the world after water, and is the most wid ...

for the dam was placed and by October next year, the reservoir had begun to fill. The Kurobe No. 4 power station was built completely underground to protect it from common avalanches in the gorge and also for nature conservation purposes. By January 1961, two of Kurobe No. 4's

Pelton turbine The Pelton wheel or Pelton Turbine is an impulse-type water turbine invented by American inventor Lester Allan Pelton in the 1870s. The Pelton wheel extracts energy from the impulse of moving water, as opposed to water's dead weight like the tr ...

s had begun operation at an initial capacity of 154 MW. In August 1962, the third turbine was in operation and by June 1963, the dam was complete at a final cost of ¥ 51.3 billion ($142.5 million (1963)). In 1973, a fourth turbine was installed and became operational; bringing the power station's production capacity to 335 MW. The fourth turbine cost ¥ 1.4 billion yen ($5 million (1973)). The first two turbines were manufactured by

Voith The Voith Group is a German manufacturer of machines for the pulp and paper industry, technical equipment for hydropower plants and drive and braking systems. The family-owned company, which operates worldwide and has its headquarters in Heid ...

and the second two by Japan's

Hitachi () is a Japanese multinational conglomerate corporation headquartered in Chiyoda, Tokyo, Japan. It is the parent company of the Hitachi Group (''Hitachi Gurūpu'') and had formed part of the Nissan ''zaibatsu'' and later DKB Group and Fuyo G ...

. The dam initiated the development of Japan's first 275kV

transmission system :''See Transmission (mechanics) for a car's transmission system'' In telecommunications, a transmission system is a system that transmits a signal from one place to another. The signal can be an electrical, optical or radio signal. Some transmissi ...

as well which allowed the transfer of electricity over greater distances. A total of 171 people died during the construction of the dam.

Specifications

The Kurobe Dam is a long and high, with variable-radius (dome)

. The dam is wide at its base, wide at its crest and contains of concrete. The dam is flanked and supported by two "wing" dams which form the

abutment An abutment is the substructure at the ends of a bridge span or dam supporting its superstructure. Single-span bridges have abutments at each end which provide vertical and lateral support for the span, as well as acting as retaining wal ...

s; the one on the left bank is long and the right is . The dam withholds a

reservoir A reservoir (; from French ''réservoir'' ) is an enlarged lake behind a dam. Such a dam may be either artificial, built to store fresh water or it may be a natural formation. Reservoirs can be created in a number of ways, including contr ...

with a capacity of of which is live (active or "useful") storage. The reservoir also has a catchment area of and surface area of . The dam's spillway is located on its crest and contains 10 wide uncontrolled openings with a maximum discharge capacity of . Three other openings exist in the dam's orifice which consist of diameter pipes, two of which can discharge a maximum of each and the third . The dam's crest elevation is above sea level while the reservoir's normal operating level is and low level is considered . The dam's power station, Kurobe No. 4, is located underground and contains four generators which are powered by Pelton turbines for a total installed capacity of 335 MW and average annual generation of 1 billion

kWh A kilowatt-hour (unit symbol: kW⋅h or kW h; commonly written as kWh) is a unit of energy: one kilowatt of power for one hour. In terms of SI derived units with special names, it equals 3.6 megajoules (MJ). Kilowatt-hours are a common bill ...

. The power station is wide, high and long. The

penstock A penstock is a sluice or gate or intake structure that controls water flow, or an enclosed pipe that delivers water to hydro turbines and sewerage systems. The term is inherited from the earlier technology of mill ponds and watermills. H ...

serving water to the power station is long and utilizes a maximum effective

hydraulic head Hydraulic head or piezometric head is a specific measurement of liquid pressure above a vertical datum., 410 pages. See pp. 43–44., 650 pages. See p. 22. It is usually measured as a liquid surface elevation, expressed in units of length, ...

of while transferring a maximum of to the turbines. The plant's surge chamber is long and high.

Access

The Kurobe Dam is the most popular hydropower site in Japan and, between late June and mid-October, water is released from its spillway for onlookers. The surrounding Kurobe Gorge is popular as well and is accessible by the Tateyama Kurobe Alpine Route. Start from Toyama Station which, from March 2015, is accessible by

Hokuriku Shinkansen The is a high-speed Shinkansen railway line jointly operated by East Japan Railway Company (JR East) and West Japan Railway Company (JR West), connecting Tokyo with in the Hokuriku region of Japan. The first section, between and in Nagano Pr ...

(trains Kagayaki or its slightly slower counterpart, Hakutaka) from Tokyo, Nagano, Kanazawa, and various other stations along the

Line. Take the train from Dentetsu Toyama Station in Toyama to Tateyama Station (Toyama) by Toyama Chihō Railway Tateyama Line (65 minutes). (Note: Toyama Station is the main station with the shinkansen hub, while Dentetsu Toyama is the station next to the main station with local lines that go through the towns of Funahashi, Kamiichi, and Tateyama, to ultimately reach Tateyama Station (Toyama)). From Tateyama Station (Toyama), take the Tateyama Cable Car to Bijodaira Station (7 minutes). From there, the Tateyama Kurobe Alpine Route bus will take you to the 2450 m high Murodō Station (50 minutes). From Murodō Station, visitors should take the Tateyama Tunnel Trolleybus (10 minutes), followed by the Tateyama Ropeway (7 minutes), and finally the

Kurobe Cable Car The , officially the , is a Japanese funicular line in Tateyama, Toyama, operated by Tateyama Kurobe Kankō. The company also operates another funicular with the same official name. The line is a part of Tateyama Kurobe Alpine Route. The line goes ...

(5 minutes). From the last stop, a 15-minute walk will take visitors to the dam. The whole trip from Toyama Station takes roughly four hours to complete one-way, and costs around 10,000 yen in transportation fees. Various accommodations are available in Murodo area as well as near Tateyama Station, for those too tired to make the trip back down into Toyama City.

In popular culture

The novel ''The Sun of Kurobe'' (黒部の太陽; Kurobe no Taiyō) dramatizes the construction of the dam. It was adapted into the 1968 film ''

The Sands of Kurobe is a 1968 Japanese drama film directed by Kei Kumai. It was Japan's submission to the 41st Academy Awards for the Academy Award for Best Foreign Language Film, but was not accepted as a nominee. Produced by its stars Toshiro Mifune and Yujiro ...

''. The television series '' Project X: Chôsensha tachi'' (2000-2005) was also based on the dam's construction. The final arc of the 2004 ''

Tetsujin 28-go , known as simply ''Tetsujin 28'' in international releases, is a 1956 manga written and illustrated by Mitsuteru Yokoyama, who also created '' Giant Robo''. The series centers on the adventures of a young boy named Shotaro Kaneda, who ...

'' anime, which takes place in a fictionalized 1950s Japan, heavily involves the construction of the Kurobe Dam. The 1961 kaiju film ''

Mothra is a fictional monster, or ''kaiju'', that first appeared in the 1961 film '' Mothra'', produced and distributed by Toho Studios. Mothra has appeared in several Toho ''tokusatsu'' films, most often as a recurring character in the ''Godzilla'' ...

'' includes an action sequence filmed at the dam before its completion. Mothra's attack causes the dam to break. Kurobe dam can be seen in the 1964 film ''

Ghidorah, the Three-Headed Monster is a 1964 Japanese ''kaiju'' film directed by Ishirō Honda, with special effects by Eiji Tsuburaya. Produced and distributed by Toho Co., Ltd., it is the fifth film in the ''Godzilla'' franchise, and was the second ''Godzilla'' film produc ...

''. Kurobe Dam features prominently in the opening scene of the 1966 film '' Gamera vs. Barugon'', in which Gamera attacks the facility’s hydroelectric plant to obtain energy in the form of fire. The dam itself then bursts after Gamera collides with it twice while flying away. The 2000 action thriller '' Whiteout'' was shot in and around Kurobe Dam, renamed Okutowa Dam in the film. The mecha anime television series '' Kuromukuro'' (2016) is mainly set in a UN research facility located around the lake.

References

External links