General Geographical Information
The Lower Likhu Hydropower Project (LLHP) is situated on the Likhu River, on the border between the Janakpur and Sagarmatha zones. The project site has Ramechap district (Janakpur) on the right side of the river’s bank and Okhaldhunga district (Sagarmatha) on the left. The climate of the project area is sub-tropical and the average annual temperature varies between 7°C in the winter and 27°C in the summer. The average annual rainfall in the area is about 1789mm.
The Likhu Khola area is a wide V-shaped valley, formed by vertical rock cliffs at the right bank and moderate dipping rocks on the left bank. It is a deep river valley, formed due to deeply incised rivers in its vicinity, and its shape is structurally controlled by joints and foliations brought about by rocks. Thick layers of colluvium and residual soil can be found along the gentle slope formed at the left bank and recent alluvial deposits can be found distributed along the River side. The general project area is mostly composed of forestland, privately owned cultivated land, and settlements.
Originating from the Zurmoche glacier below the Likhu Dhuni Himal, the Likhu River (or Likhu Khola) is a dendritic glacial-fed tributary of the Sun Koshi River. The major tributaries of the Likhu Khola above the headworks area are Nupche Khola, Piparang Khola, Sapsu Khola, Chulepu Khola, Simling Khola, Bikha Khola, Bhakanji Khola, and Bhumu Khola.
The general arrangement of the project is composed of headworks, water-conveyance arrangements, and a powerhouse on the right bank of Likhu Khola.
The headworks is situated in Saipu VDC about 800m upstream of Taruke Khola at approximately 86°15’00” E Longitude and 27°25’10’ N Latitude. It comprises of a boulder lined free flow diversion weir, two gated undersluices, a side intake arrangement, three chambered gravel traps, an approach canal, and three chambered settling basins with flushing arrangements.
A 1285m long headrace penstock pipe, that is buried underground, conveys water from the settling basin to the headrace tunnel inlet. The pipe, for the purpose of minimizing concrete quantity, headloss, and earthworks, is aligned straight as far as practicable and passes across the terrain and cultivated land while following the right bank of Likhu River.
The headrace tunnel starts from Sirise and ends at Ratma where a surge shaft has been envisioned. The proposed surge shaft will be situated in Ratmata of Bijulikot VDC and be preceded by a planned rocktrap.
A steel penstock pipe about 280m in length and with a 3.75m internal diameter conveys the flow from the proposed headrace tunnel to the powerhouse. The pipe is supported by anchor blocks and concrete support piers will be provided as an intermediate support between the bends of the pipe.
The powerhouse is situated in Lorkhubesi of Bijulikot VDC on an alluvial terrace formed by Larkhu Khola and Likhu Khola. It is a semi surface structure, 27.3 m in length and 22.0m in width, that accommodates two generating units of 14.05MW capacity.
A 27km long 132 kV transmission line to Khimti substation will be constructed for the purpose of power evacuation. However, the evacuation of power generated by LLHP could also be altered into a 10km long 132kv transmission line if the construction of Likhu IV substation is completed during the implementation of LLHP.
There are two primary routes which can be used to access the project area.
The project’s headworks area can be accessed by using a route from Kathmandu to Sirise via Nayapul-Hala-Dhobi-Sirise. The road has been blacktopped from Nayapul to Hala and the rest of it is gravelled.
Another route, from Kathmandu to Saghutar via Nayapul-Hala-Manthali-Salu-Deurali-Saghutar, can be used to access the Powerhouse. The road for the second route is blacktopped till Manthali and the remainder has been graveled.
According to the local branch of Nepal Telecom, almost all the VDCs in Ramechhap and Okhaldhunga district have been facilitated with working network services. In addition to services provided by the NTC, the mobile network services provided by Ncell and CDMA also work in the project area.
Socio Economic Profile
Although the average literacy rate of the districts is low (39.05% for Ramechhap and 49.12% for Okhaldhunga), the literacy rate of families directly affected by the project is relatively high at 94.73%. However, social stratification based on castes and gender still prevails to a degree in the project area.
The majority of the locals are engaged in agriculture and only a small fraction of the populace is engaged in other occupations. The primary agricultural produce of the area appears to be paddy, maize, wheat, millet, and potatoes; the livestock reared is mostly cattle, buffalo, goats, pigs, and poultry. Plants/crops like cauliflower, cabbage, carrot, and seasonal fruits are also grown in the area.
The locals of the project area are also very dependent on the nearby forests, particularly for firewood which is used as the primary source of fuel. Timber and bamboo are also essential requirements for domestic construction purposes. The locals also gather Non-Timber Forest Products, like medicinal plants, from the community forests. However, forest cultivation appears to be solely for domestic purposes and not for commercial reasons.
A significant amount of locals are also dependent on remittance from relatives employed in major cities of Nepal or foreign lands