MATHILLO MAILUNG KHOLA JALVIDHYUT AAYOJANA (14.3 MW)
Mathillo Mailung Khola Jalvidhyut Aayojana (MMKJA) is a 14.3 MW run-of-river (RoR) project located on Uttargaya Rural Municipality ward no: 1 (Previously Haku and Dadagaun VDC), Rasuwa District, Province No. 3 Nepal. The project is being developed by Mathillo Mailun Khola Jalvidhyut Ltd. Shankha Park, Dhumbarahi, ward no. 4 Kathmandu M. C., Nepal (hereinafter referred to as “the Employer”). The license boundaries of the project area are: latitude 28º 08’ 00” N to 28º 05’ 56” N, and longitude 85º 11’ 00” E to 85º 13’ 00” E. The project diverts Mailung River with a watershed area of 72 km² at the proposed Intake.
The proposed Headworks of MMKJA consists of Boulder Lined weir, gated Undersluice, Side Intake with two orifices, Gravel Trap, Approach culvert, two chambered Settling basin and Headrace Canal up to Headrace tunnel Inlet portal. The Headrace tunnel (HRT) is proposed to be of inverted D-shaped. It is planned to excavate the Headrace tunnel from two different faces namely: HRT Inlet portal and HRT Outlet portal. An underground Forebay is proposed at the end segment of Headrace tunnel about 157 m upstream side of the HRT Outlet portal. An underground steel Penstock pipe with two vertical shafts and an inclined tunnel will convey water from underground Forebay to surface Powerhouse which accommodates two generating horizontal axis Pelton Turbines. After generating power, the diverted water will be discharged back to Mailung River through a Tailrace culvert. There will be 11/132 kV Switchyard beside the Powerhouse. From the Switchyard, the generated power will be evacuated to Integrated Nepal Power System (INPS) through a 15 km long, 132 kV transmission line up to Trishuli 3B Hub Substation of Nepal Electricity Authority (NEA) which is under construction.
The Headworks area of MMKJA is located in Uttargaya Rural Municipality ward no. 1, Phedi Odar. The Weir axis is located approximately about 2050.5 m (weir crest level) above mean sea level (amsl). The Headrace tunnel alignment passes through right bank of the Mailung River which is approximately 1855 m up to Forebay. The Powerhouse is proposed to be located on the right bank of the Mailung River in Uttargaya Rural Municipality ward no. 1, at confluence of Raman Kholsi and Mailung River towards Mailung River. At the Powerhouse location, the terrace is narrow and the vertical shaft lies just 170 m upstream of Powerhouse location. The entire project components such as Headworks, Headrace tunnel, Forebay, Penstock, Vertical Shaft, and Powerhouse lie at right bank of Mailung River in Uttargaya Rural Municipality.