The Idukki Dam is a double curvature arch dam constructed across the Periyar River in a narrow gorge between two granite hills locally known as Kuravan and Kurathi in Idukki, Kerala, India. At , it is one of the highest arch dams in Asia. It is constructed and owned by the Kerala State Electricity Board. It supports a 780 MW hydroelectric power station in Moolamattom, which started generating power on 4 October 1975. The dam type is a concrete, double curvature parabolic, thin arc dam. The Indo-Canadian project was inaugurated by the Prime Minister Indira Gandhi on February 17, 1976. This dam was constructed along with two other dams at Cheruthoni and Kulamavu. Together, the three dams and Two saddle dams, Kulamavu Saddle Dam (Near Junction) and Kulamavu Saddle Dam (Right Bank) have created an artificial lake that is in area. The stored water is used to produce electricity at the Moolamattom Power house, which is located inside nearby rocky caves. Narakakkanam, Azhutha, Vazhikkadavu, Vadakkepuzha and Kuttiar diversion schemes were later added to augment the Idukki reservoir . History Early surveys The idea of constructing a dam for power generation was first conceived in 1919 in a report submitted by Italian engineer Jacob to the Travancore government, which was rejected. As per history, Shri Chemban Karuvellayan Kolumban, the head of 'Oorali' tribe during 1922, showed the way to the Malankara Estate Superintendent W.J.John and his friend AC Thomas Edattu, who were on hunting trip to forests near the present Arch Dam. Upon hearing the legend of Kuravan and Kurathi Hills, Thomas impressed by the sight of water flow between the mountains; suggested the spot suitable for an Arch dam. In 1932, W.J.John submitted a report to the Government of Travancore on the possibility of constructing a dam at Idukki for Power Generation. In 1935, assembly member Shri.K.A.Narayana Pillai brought the Idukki project to the attention of Government of Travancore. Italian engineers Angelo Omedayo and Clantheyo Masele conducted a study in 1937 but things didn't go forward. In 1947, a preliminary investigation report was prepared and submitted by Sri. P. Joseph John, then The Chief Electrical Engineer to the Government of Travancore. It was during 1956 that the Central Water Commission conducted a detailed investigation based on the Government's request. The project report was prepared in 1961 and the Planning Commission accorded sanction for implementing the scheme in 1963. In 1964,