The Kurobe Dam or Kuroyon Dam, is a variable-radius arch dam on the Kurobe River in Toyama Prefecture, Japan. It supports the 335 MW Kurobe No. 4 Hydropower Plant and is owned by Kansai Electric Power Company. At in height, it is the tallest dam in Japan. 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 Kansai Electric Power Company was formed to provide electric power for the Kansai region 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 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 for the dam was placed and by October of the 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 turbines 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. 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. The first two turbines were manufactured by Voith and the second two by Japan's Hitachi. The dam initiated the development of Japan's first 275kV transmission system 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 arch dam. 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 abutments; the one on the left bank is long and the right is. The dam withholds a reservoir with a capacity of of which is live 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. The power station is wide, high and long. The penstock serving water to the power station is long and utilizes a maximum effective hydraulic head of while transferring a maximum of to the turbines. The plant's surge chamber is long and high.
A novel turned film, Kurobe no Taiyō, starring Yujiro Ishihara, recounts the drama of the project. The P.A.Works's mechaanime television series Kuromukuro is mainly settled in a UN research facility located around the lake, while the NHK television series Project X was also based on the dam's construction. The 1961 kaiju film Mothra, directed by Ishirō Honda, includes an action sequence filmed at the dam before its completion. Mothra's attack causes the dam to break. Kurobe dam was destroyed by Gamera in War of the Monsters . Kurobe dam was also seen in Ghidorah, the Three-Headed Monster. Additionally, the final arc of the 2004 Tetsujin 28-go anime, which takes place in a fictionalized 1950s Japan, heavily involves the construction of the Kurobe Dam.
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 also 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 from Tokyo, Nagano, Kanazawa, and various other stations along the Hokuriku Shinkansen Line. Take the train from Dentetsu Toyama Station in Toyama to Tateyama Station by Toyama Chihō Railway Tateyama Line.. From Tateyama Station, take the Tateyama Cable Car to Bijodaira Station. From there, the Tateyama Kurobe Alpine Route bus will take you to the 2450 m high Murodō Station. From Murodō Station, visitors should take the Tateyama Tunnel Trolleybus, followed by the Tateyama Ropeway, and finally the Kurobe Cable Car. From the last stop, a 15-minute walk will take visitors to the spectacular 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.
