Main Civil Works
Headworks and Powerhouse
Till date almost 99% of concrete works at Undersluice, 98% at intake (orifice structure), 91% at U/s floodwall, 77% at gravel trap and 76% at intake canal has been completed. Further, the concreting works at weir and stilling basin have been commenced by the Civil Contractor from this dry season after re-coffering the river. Till date 30% concrete works at weir, 40% at stilling basin and 46% at U/s blocket have already been completed. Also, d/s right floodwall and cutoff-wall at headworks have been already constructed. Further, the excavation works on the conveyance tank and settling basins are in progress.
The excavation works at Powerhouse has already been completed. The concrete works at tailrace floodwall has also been completed. Further, the concreting works at Powerhouse is ongoing. Till date almost 78% concreting works at Powerhouse and 40% at Tailrace culvert has been completed. The Contractor has excavated more than 31,000 m3 of earthwork in the penstock region till date which is more than 50% of the estimated volume of earthwork.
Underground Works
Till date, about 82% by length of the underground works has been excavated along with necessary supports works. The progress by volume is about 67% due to slow excavation of the Settling Basins with much large cross section (i.e. 150 m x 13.5 m x 17.5 m). About 5,422 m length of the tunnel network has been excavated till date out of total 6625m. 3,367 m long headrace tunnel with an excavation size of 6.5 m x 6.5 m joins the Connecting tunnels at Headworks with the penstock pipe at outlet. There are two work fronts for HR, one from Adit tunnel and another from outlet portal. About 2,868.66 m has been excavated till the end of January 2022, from two different faces. The Contractor has already excavated almost 28% of earthwork volume in three fronts of underground settling basin. Further, the Contractor is carrying out the widening works of 80 m deep surge shaft to its design diameter of 16m up to a depth of about 32 m from the top level of crown.