Hydropower: Work on the construction of an exploratory drift for the 422 megawatt Nyera Amari integrated hydroelectric project powerhouse for Nyera Amari II was inaugurated on October 19 at Martshalla gewog in Samdrupjongkhar.
This was following the excavation of an exploratory drift of 80 metres for the dam of Nyera Amari I located at Pangzam in Thrimshing inTrashigang, which was inaugurated in September. The work is expected to be completed by the end of this month.
Druk Green Power Corporation awarded construction of exploratory tunnels for both the projects to the Construction Development Corporation Limited (CDCL) in September 2016. A memorandum of understanding was signed in March 2016 between the two companies.
The Samdrupjongkhar dzongdag graced the inaugural ceremony.
The project sites of Nyera Amari I are located at Pangzam (dam) in Trashigang and the powerhouse at Gomdhar in Samdrupjongkhar. For Nyera Amari II, the dam and powerhouse sites are located at Gomdhar and Martshalla gewogs in Samdrupjongkhar respectively.
The work includes development of drift portals and excavation of drifts, which will be carried out fully by Bhutanese employees for the first time in hydropower construction.
CDCL is the first national company taking steps in construction of a hydropower project.
The total length of drift is 1,610 metres in both Nyera Amari I and II and will be completed in 2018. The work will be carried out simultaneously in both the sites.
The total contract amount of the underground excavation is about Nu 88.26 million.
The exploratory drift is a small underground tunnel that allows a physical approach to the underground structures or caverns, abutments of the dam and further will facilitate the conduct of rock mechanic tests for preparations of the final Detailed Project Report (DPR) of the project.
“It is an immense pleasure to be part of this team which has broken the ice of getting into hydropower construction by Bhutanese albeit being small in the beginning. We hope to participate in the major construction of hydropower components in the near future,” CDCL general manager Ugyen Gyeltshen said.
The project is to be developed in two stages, the 125 MW NAHP-I and the 315 MW NAHP-II. These two stages of the project lie entirely along the left bank of the Nyera Amari. The DPR is estimated to cost Nu 365 million for the preparation, is expected to be completed towards the end of 2017.
Yangchen C Rinzin | Samdrupjongkhar