One of the highest Arch Dam In Asia’s Kerala’s Idukki Dam is going to be opened for the first time in 26 years, owing to rising water level of the Periyar River following heavy monsoon rains in Kerala. On Tuesday night, the water level in the Idukki reservoir touched 2,397 feet against its maximum of 2,403 feet and just 6 feet short of the full level, prompting the authorities to issue an orange alert in Idukki, Ernakulam and Kottayam districts
The opening of the dam would lead to large-scale evacuation of residents of nearby areas. Thus, in the meeting it was decided that the disaster management officials will take a stock of buildings in and around 100 metres of the dam area with the help of satellite pictures and collect details of people residing in those buildings to aid in the evacuation process
An orange alert is out, with the District Collector Jeevan Babu K issuing it at 9.10 pm on Monday. Should the rain remain incessant, people settled downstream of Cheruthoni Dam – particularly in the Thadiyampadu, Karimban and Injivarakkuth areas on the banks of the Cheruthoni River – have two or three days to move out of their homes and shelters.
Highest Arch Dam
The Idukki Dam is a double curvature arch dam constructed across the Periyar River in a narrow gouge between two granite
ills locally known as Kuravan and Kurathi in Kerala, India. At 167.68 metres (550.1 ft), 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 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’ race during 1922, showed the way to the Malankara Estate Superintendent W.J.John and his friend AC Thomas Edattu, 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 materialized 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.
Its Third Time
Twice in the past, the shutters (of Cheruthoni) had to be opened; during the northeast monsoon (October to December) on both occasions. The first time was in 1981 (when the shutters were repeatedly opened and shut between 29 October and 13 November) and the second time was in 1992 (when they were kept open for 12 days from 12 to 23 October). On both occasions, the water level in the dam touched the brim only when the storage built up during the southwest monsoon (June to September) was augmented by the inflow received immediately afterwards following heavy downpour early in the northeast monsoon