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The Vajont Dam (or Vaiont Dam)〔(【引用サイトリンク】title=Vaiont Dam photos and virtual field trip )〕 is a disused dam, completed in 1959 in the valley of the Vajont River under Monte Toc, in the municipality of Erto and Casso, 100 km (60 miles) north of Venice, Italy. One of the tallest dams in the world, it is high, wide and thick at the base and wide and thick at the top. The dam was conceived in the 1920s, designed by Carlo Semenza, and eventually built between 1957 and 1960 by Società Adriatica di Elettricità ("SADE", or "EDIS") (English: ''Adriatic Energy Corporation''), the monopoly electricity supply and distribution monopoly in northeastern Italy, which was owned by Giuseppe Volpi di Misurata. In 1962 the dam was nationalized and came under the control of ENEL as part of the Italian Ministry for Public Works. It was described as 'the tallest dam in the world', intended to meet the growing demands of industrialization, and as of 2010 is still one of the tallest in the world. On 9 October 1963, during initial filling, a massive landslide caused a man-made megatsunami in the lake in which 50 million cubic metres of water overtopped the dam in a 250-metre (820 ft) wave,〔 leading to the complete destruction of several villages and towns, and 1,917 deaths. This event occurred when the company and the Italian government dismissed evidence and concealed reports describing the geological instability of Monte Toc on the southern side of the basin, and other early warning signs reported prior to the disaster. Numerous warnings, signs of danger, and negative appraisals had been disregarded, and the eventual attempt to safely control the landslide into the lake by lowering its level came when the landslide was almost imminent and was too late to prevent it. Although the dam itself remained almost intact, and two thirds of the water was retained behind it, the landslide was much larger than expected and the impact brought massive flooding and destruction to the Piave valley below. Although the wave only contained a third of the dam's contents, it was still ten times higher than calculations had predicted. On 12 February 2008, while launching the International Year of Planet Earth, UNESCO cited the Vajont Dam tragedy as one of five "cautionary tales", caused by "the failure of engineers and geologists". ==Construction== The dam was built by SADE (''Società Adriatica di Elettricità'', English: ''Adriatic Energy Corporation''), the electricity supply and distribution monopoly in northeastern Italy. The owner, Giuseppe Volpi di Misurata, had been Mussolini's Minister of Finances for several years. The 'tallest dam in the world', across the Vajont gorge, was conceived in the 1920s to control and harness the rivers Piave, river Mae and the Boite stream, and to meet the growing demand for power generation and industrialization, but not until the confusion after Mussolini's fall during World War II was the project authorized on 15 October 1943. The dam had a volume of 360,000 m³ and held up to 168,715,000 cubic meters of water. The dam and basin were intended to be at the centre of a complex system of water management in which water would have been channeled from nearby valleys and artificial basins located at higher levels. Tens of kilometres of concrete pipes and pipe-bridges across valleys were planned. In the 1950s, SADE's monopoly was confirmed by post-fascist governments and it bought the land despite opposition by the communities of Erto and Casso in the valley, which was overcome with government and police support. SADE stated that the geology of the gorge had been studied, including analysis of ancient landslides, and that the mountain was believed to be sufficiently stable. Construction work started in 1957, but by 1959 shifts and fractures were noticed while building a new road on the side of Monte Toc. This led to new studies in which three experts separately told SADE that the entire side of Monte Toc was unstable and would likely collapse into the basin if the filling were completed.〔T. Merlin, ''Sulla pelle viva'', Cierre Edizioni, Verona, 1993, pp. 59 and 73.〕 All three were ignored by SADE. Construction was completed in October 1959, and in February 1960, SADE was authorised to start filling the basin. In 1962 the dam was nationalized and came under the control of ENEL as part of the Italian Ministry for Public Works 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Vajont Dam」の詳細全文を読む スポンサード リンク
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