Thank you, Idukki: Power project completes half a century

IDUKKI: The Idukki Hydroelectric Project, the largest underground hydroelectric project in the country, marks 50 years today. The Indo-Canadian project was dedicated to the nation on February 12, 1976, by then Prime Minister Indira Gandhi.

The history of the project dates back to 1932. W.J. John, the superintendent of Malankara Estate, met a tribal elder named Karivellayan Kolumban during a hunting trip in the forests of Idukki. Kolumban showed him the scenic gorge between the Kuravan and Kurathi hills, where the Periyar River flows. John felt that building a dam there could help in power generation and irrigation. With the help of his engineer brothers, he conducted studies and submitted a report, but the Travancore government rejected the proposal.

In 1961, the Central Water and Power Commission studied the site and prepared a design for the dam. The project received approval in 1963.

The Idukki project consists of three dams- Idukki, Cheruthoni and Kulamavu. The Idukki arch dam, built across the Periyar River between the Kuravan and Kurathi hills, rises over 500 feet. The Cheruthoni dam with shutters is located nearby, while the Kulamavu dam is 22.5 km away.

Water from the Kulamavu dam is carried through a butterfly valve system to the underground power station at Moolamattom, located 46 km away. The power station is built entirely inside a mountain, making it the only construction of its kind in Asia. The only access to the powerhouse is through a 1,966-foot-long tunnel, making evacuation difficult in case of an emergency.

During construction, 85 workers died in accidents out of 15,000 workers involved. Several minor and major accidents have occurred since then. In 2011, two engineers, including a woman, died in an explosion. The project originally cost Rs 220 crore. Today, it would cost at least Rs 3,000 crore to build.

Kerala’s energy source
The Idukki project supplies about 35 percent of Kerala’s electricity needs. The Moolamattom power house has six generators, each with a capacity of 130 megawatts. When all generators function together, up to 18 million units of electricity can be produced per day.

Second phase yet to begin
The first-stage environmental clearance for the second Idukki power project was granted by the Union Ministry of Environment and Forests in June 2022. However, the Detailed Project Report (DPR), which must be prepared by Water and Power Consultancy Services Limited under the Union Ministry of Jal Shakti, is still pending. Around a dozen more approvals are required before the project can begin.

Laser show to begin tomorrow
A laser show will begin at the Idukki dam tomorrow. State Minister K. Krishnankutty will inaugurate the event at 11:30 am. The show is being organised by the Kerala Hydel Tourism Centre at the backdrop of the Idukki arch dam.

The laser show will be displayed across a 400-metre-wide and 500-metre-high surface of the dam. It will feature special video effects highlighting the history of the dam’s construction and the growth of the Kerala State Electricity Board (KSEB).