The idea of constructing a dam for power generation was first conceived in 1919. As per history, Shri Kolumban, the head of ‘Araya’ race during 1922, showed the way to the Malankara Estate Superintendent and his friend Thomas, who were on hunting spree in the forest, the spot of present Arch Dam. He told them of the legend of Kuravan and Kurathi Hills. Mr. Thomas was impressed by the sight of water flow between the mountains and it was his idea that has materialised in the form of Idukki Arch Dam. Sri. W.J.John of Malankara Estate submitted a report to the Government of Travancore in 1932 on the possibility of constructing a dam at Idukki for Power Generation.