Work involves boring twin inclined pressure shafts at 30 degrees to the horizontal. Gammon India successfully bored the first inclined shaft of 4.88m diameter and 1545m length on 18 March using a double shield tunnel boring machine. This shaft – the longest pressure shaft for any hydro project in the world – was completed in a record time of eight and a half months.

The company is confident of completion of the second pressure shaft, with technical assistance of Austria’s M/s Jaeger and Seli.

The Parbati scheme, located in the Himalayan Mountains, is being constructed for India’s National Hydroelectric Power Corporation. The scheme is seen of special importance because of the unusual geological conditions found in the project area.