Shimla, Jul 1 (IANS): Acieving what they called a major milestone, authorities executing a major hydroelectricity project in Himachal Pradesh on Wednesday said they have managed to connect two faces of a headrace tunnel despite high geo-thermal temperatures.

The 450-MW Shongtong Karchham project is being constructed by state-run Himachal Pradesh Power Corp Ltd (HPPCL) on the Sutlej river in Kinnaur district.

The breakthrough was achieved by connecting two faces of the headrace tunnel in a length of 2.70 km between adit two and adit three. There has been high geo-thermal temperature of 45 to 57 degrees Celsius between these adits, an official statement said.

In spite of such high geologically difficult conditions encountered during the excavation, the target was achieved by the HPPCL.

Out of total of 7.7 km-long headrace tunnel, 6.1 km of heading excavation has been completed. The excavation of the powerhouse and transformer cavern has also been completed.

The project is a run-of-the-river project with diversion barrage near Powari village.

When completed, the project will generate 1,579 million units of power per annum in 90 per cent dependable year.

It is being constructed through the engineering procurement and construction mode.

The funding arrangement of Rs 1,600 crore for balance works of the project has been taken up with the World Bank.

The project will generate energy at a competitive rate of Rs 6.3 crore per MW against the normal average cost of Rs 10 crore per MW.

The project on commission will earn revenue of Rs 500 crore per annum.