Project completes 15pc of tunnel works using TBMThe Bheri Bhabai Multi-Purpose Diversion Project has completed digging 15 percent of the tunnel since the work started two-and-a-half months ago, thanks to Tunnel Boring Machine (TBM).
The Bheri Bhabai Multi-Purpose Diversion Project has completed digging 15 percent of the tunnel since the work started two-and-a-half months ago, thanks to Tunnel Boring Machine (TBM). The project requires a tunnel spanning 12 kilometres and 1,800m has been dug so far using the TBM.
Senior division engineer Rukmangat Khanal said, “As the machine was utilised for the first time in Nepal, we still harboured many concerns. However, no problem has been recorded yet. The tunnel will reach the bottom of the Harre Mountain soon.” He said that if TBM can dig the tunnel at this pace, then the project will meet its deadline of March 2020. Anil Khatri, geologist of the project, said that the TBM can dig 20-25 metres daily if used for 18 hours a day. According to him, the TBM is operated by 84 Chinese technicians and 600 Nepali workers round the clock. The total length of the tunnel is 12 kilometres and its width is 5.6 metres. Before the TBM was introduced in Nepal, tunnels used to be dug exclusively by drilling and blasting. Geologist Khatri said, “Due to sensitive geology of the project site, it would not have been possible to dig the tunnel by blasting. Then, the Department of Irrigation made a proposal of buying the TBM. As the use of TBM has been successfully tested and utilised, the government can use similar machines for other projects in the future.” This machine was manufactured by the American company Robbins and brought from China. Then, US company handed over the TBM to China Overseas Engineering Group, the designated civil contractor for the project. The Chinese contractor installed a 4 MW diesel plant at site of the project to facilitate the required power to operate the machine.
The Bheri Babai Multipurpose Diversion Project, a national pride project located at Bheri-Ganga Municipality in Surkhet district, will have a 15-metre-high dam. It will divert 40 cubic metres of water per second from the Bheri River to the Babai River. The water will be used to irrigate 51,000 hectares of land round the year in Banke and Bardia districts. The project will also generate 48 MW of electricity.
The irrigation-cum-hydroelectric project is one of the strategic projects of the country, as it is expected to ease the food crisis in the Mid-Western Region by increasing agricultural yield. The project will cost Rs16.5 billion to complete.
If irrigation can be maintained throughout the year, it is estimated that agricultural yields will increase by up to Rs3 billion per year. The project also forecast electricity generation worth Rs4 bilion annually.