<P> Idukki Dam is 168.91 m (554.2 ft) tall, constructed between the two mountains - Kuravanmala (839 m (2,753 ft)) and Kuravathimala (925 m (3,035 ft)). Length of the dam on its top is 365.85 m (1,200.3 ft). It has a width of 7.62 m (25.0 ft) in the top and 19.81 m (65.0 ft) in the bottom . About 464,000 m (16,400,000 cu ft) of concrete was used in the construction of the dam . This project is situated in Idukki District and its underground power house is located at Moolamattom which is about 43 km (27 mi) from the dam . One thing to be noted is, Idukki Arch dam doesn't have any shutters to be opened so it has to rely on the Cheruthoni dam to maintain the reservoir water level . </P> <P> The Project harnesses a major portion of the power potential of Periyar, the largest river in Kerala, by the creation of a reservoir of 2,000 M. cum (2 Billion Tonnes) capacity, diversion of waters thus impounded through a water conductor system consisting of a power tunnel and two underground pressure shafts to an underground power house situated in Moolamattom . The installed capacity of the Power House is 780MW consisting of 6 Units of Pelton - type turbines with a power generation capacity of 130 MW each . The regulated waters of Periyar falls through a drop of about 669.2 m (2,196 ft) while generating power in the underground power house. The generated power is given to two sub stations, One double circuit line to Kalamassery; one single circuit line to Tamil Nadu; One single circuit line to Pallom, 3 feeder bays for future . </P> <P> The tail waters flowing to Kudayathurpuzha through tunnel and open channel is diverted for irrigation purposes in the Muvattupuzha Valley . </P> <P> Tourist destination and attraction </P>

Where does the water from idukki dam go