Project in brief
Located at a distance of 700 Km northeast of Kathmandu, Middle Mewa HPP is one of the very few Peaking Run of River (PROR) type projects in Nepal. The project is proposed in Mewa river in Taplejung District of eastern Nepal. The project shall utilize the design discharge of 18.76 m3/s to generate 73.5 MW of electricity with daily peaking of 6 hours. The project is accessible through a 32 km of access road from Banande Bazar located at Mechi Highway.
Project Details
- Project Name : Middle Mewa Hydropower Project
- Type of Scheme : Peaking Run-of-River (PRoR)
- Installed capacity : 73.5 MW
- Project Location : Mikhwa Khola & Meringden R. Municipality, Taplejung
- Power Evacuation to: Dhungesanghu/ Hangpang Substation (Approx. 14 km from Powerhouse)
Salient Features
- Gross Head : 471.47 m
- Net Rated Head : 452.45 m
- Design Discharge : 18.76 m3/s
- Headrace Tunnel : 5314 m
- Net Annual Energy : 436.08 GWh
Progress Updates

Civil Works
- Headworks excavation works completed.
- Steel lining at right side dam completed. Left side dam PIT test completed and rectification grouting, shear key concreting works completed and raft concreting works ongoing.
- Concrete works at the settling basin, desander transition, head pond to HTR inlet connection part, and counterfort retaining wall ongoing.
- Headrace tunnel between Face 1 and Face 2 breakthrough completed, invert cleaning, final support and concrete works ongoing. Headrace tunnel at Face 3 and Face 4 diverted due to weak geological conditions requiring additional 95 m tunnel length.
- Diversion done from both Face 3 and Face 4, and excavation works ongoing in both faces.
- Concrete works at surge shaft and Anchor Block 1 ongoing.
- Concrete infill work at both Vertical shaft 1 and 2 completed.
- Concrete works at LPT ongoing. Powerhouse cavern finishing works ongoing.
- Powerhouse MAT portal busduct support concrete works completed.
- Powerhouse switchyard control building concrete works completed and finishing works ongoing.
- Tailrace tunnel invert and shear wall concreting works completed. Switchyard foundation and protection works ongoing

Hydromechanical Works
● Fabrication of first-stage and second-stage embedded parts of all gates completed.
● Fabrication and erection work of Bifurcations and Bellmouth completed. Pressure test is successfully completed.
● Fabrication of gate lift of radial sluice gate, scour sluice gate, floating gate, settling basin inlet/outlet/flushing gates, turbine outlet gate, tailrace outlet stoplog and settling basin flushing stoplog ongoing.
● Steel plates for penstock pipe delivered to the site and fabrication works completed
● Erection of penstock pipe at upper-pressure tunnel completed. ● Erection of bend 3 at anchor block 1 is ongoing.
● Erection of penstock pipe at Vertical Shaft 1 completed.
● Erection of penstock pipe at Intermediate-pressure tunnel ongoing, 160m completed (46m remaining).
● Erection of penstock pipe at Vertical Shaft 2 completed.
● Erection of pipes at LPT ongoing.
● Erection of steel lining at right side dam completed.

Electromechanical Works
● Turbine housing/bifurcation installation for all three units along with second stage concreting completed.
● Installation of turbine nozzles of all three units completed. ● Installation of all three MIVs completed.
● Installation of all three units of generators completed.
● Bus duct installation ongoing.
● 11kV switchgear panels, LVAC panels, DC system panels, cable trays manufactured and reached at site. Installation ongoing.
● Switchyard equipment like Lightning Arrestors, Circuit Breakers, Current TransformerPotential Transformers, Disconnecting Switches, etc. reached site. Installation of the steel structures and switchyard equipment is ongoing.
● Installation of Four numbers of 132kV bays completed, fifth bay installation works ongoing.
● Earthing and civil foundation works for 132kV bays at Dhungesanghu Substation works ongoing

Transmission Line Works
● All transmission line tower stubs, tower sets and accessories delivered to the site store.
● Excavation for all tower foundations is completed.
● Concrete works completed for 34 tower foundations.
● Tower erection completed for 34 towers.
● Tower protection works completed for 21 towers and ongoing for the remaining towers.
● Conductor stringing works completed between 8 towers and ongoing between 6 towers.