By Lynda Myer
Following the launch of the double-shield TBM, Nepal’s Sunkoshi Marin Diversion Multipurpose Project (SMDMP) has reached a key landmark.
Linking to a new surface powerhouse on the Marin River, construction process of the 13.1km headrace tunnel will commence by starting up of the intended TBM.
In order to producing almost 30MW of energy, the available head between the intake and powerhouse is due to be used, while water diverted from the Sunkoshi River to the Marin River through the tunnel will be used to irrigate about 122,000ha of farmland in the districts of Dhanusha, Mahottari, Sarlahi, Rauthat and Bara in the Terai Plains.
Also a conventional concrete diversion weir structure (barrage and under sluice bay) across the Sunkoshi River, is a subset of this multi-purpose project. Meanwhile in order to removing silt, the diverted water is slated to be passed through a desander before being conveyed via the new headrace tunnel.
Being considered as a National Pride project by the Nepalese government, SMDMP is going to combine hydropower and irrigation benefits.
Moreover, in February 2021, the tunneling contract of Sunkoshi Marin Diversion Multipurpose project was granted to China Overseas Engineering Co.
