Tunnel borer may be used at Dudhkoshi projectBuoyed by the unexpected success of the tunnel boring machine (TBM) at the Bheri Babai Diversion Multipurpose Project, the Nepal Electricity Authority (NEA) has planned to use similar equipment during the execution of the Dudhkoshi Storage Hydroelectric Project which is currently under study.
Buoyed by the unexpected success of the tunnel boring machine (TBM) at the Bheri Babai Diversion Multipurpose Project, the Nepal Electricity Authority (NEA) has planned to use similar equipment during the execution of the Dudhkoshi Storage Hydroelectric Project which is currently under study.
Managing director of the state-owned power utility Kulman Ghising has directed the consultant to prepare a design for the project including the use of TBM to dig tunnels. Ghising issued the instruction during an inspection visit to the project site on Saturday. The Dudhkoshi project involves digging 13 km of tunnel, and the NEA is keen to use the TBM as it is fast.
The Bheri Babai project is the only project in Nepal where such technology is being used, and the results have been impressive. The project has finished digging more than 38 percent of the 12 km tunnel using the TBM in six months. As of Sunday, 4.62 km of the tunnel had been completed. The TBM will be used at the Dudhkoshi project only after a study shows that it is feasible. “We have asked the consultant to conduct a geological test at the project site where the tunnel will be constructed,” said Basanta Shrestha, the NEA appointed project chief. “If the test shows it is all right to use the TBM, we will go for it.”
In May 2016, the NEA appointed a joint venture of ELC Electroconsults SPA and NEWJEC Inc to prepare an updated feasibility study and detailed design for the storage project. As per the contract signed with the power utility, the consultant is required to submit the study and design report to the NEA by January 2019. The power utility has asked the consultant to design the project with an installed capacity of 800 MW. Originally, the NEA had conducted a feasibility study for the project in 1998 with an installed capacity of 300 MW. The study reported that the planned project was viable and attractive. However, the NEA plans to develop the project with the higher installed capacity and make it a major project of Province 1.
According to the NEA, Manila-based multilateral lender Asian Development Bank has pledged to provide financial assistance to develop the project. Similarly, the power utility is planning to issue shares to locals. “We are committed to expediting the construction of the project as soon as the study is completed,” said Ghising. Locals of Khotang and Okhaldhunga where the project is located are euphoric at the planned construction of a large hydropower project in their area.
“We are eagerly waiting for the construction of the project,” said Lila Nath Niraula, chairman of Rawabeshi Rural Municipality in Khotang district. “The project will inundate huge tracts of paddy fields, but it is an acceptable trade-off.”