The tailwaters make the Thodupuzha river at Thriveni sangamam which is 1 km. from Moolamattom Power Station. Moolamattom Power Station is the biggest underground Hydro-electric Project in India. The water from the Idukki Dam is carried by the underground pipes to the power station. The installed capacity of the Power House is 780 MW consisting of 6 generator units of 130 MW each.
The regulated waters of Periyar falls through a drop of about 669.2 metres (2195 feet) while generating power in the underground power house. Project work on this power station was initiated by Sri. E.U.Philipose, Superintending Engineer, Kerala State Electricity Board in 1964. Visitors are restricted to enter the Moolamattom Power Station due to security reasons.
A landlocked region in Moolamatton here high ranges and wooded valleys are girded by three main rivers – the first river Peryar flowes throuth the Idukki Hydro Electric Project’s and that spillway water named as Periyar, the second one is Thalayar beginning from Vagamon, Pullikanam hills and another one is Thodupuzhayar. The Teak plantation is a memorable one for every one in Moolamattom. Idukki hydro electric project have 780 megawatt capacity. The distance from Idukki to this place is 38 Kms. The place is in Moolamattom, left divertion from Asoka Junction in between the Puliyanmala- Thodupuzha road
