Available online www.ejaet.com European Journal of Advances in Engineering and Technology, 2015, 2(1): 50-54 Research Article ISSN: 2394 - 658X 50 Delineation of Run of River Hydropower Potential of Karnali Basin- Nepal Using GIS and HEC-HMS Raghu N Prajapati Civil Engineering Department, Nepal Engineering College, Changunarayan, Bhaktapur, Nepal raghunp@nec.edu.np _____________________________________________________________________________________________ ABSTRACT Water resources are the most important natural resources because they are not only renewable natural resources but also abundantly available in Nepal. A favorable topographic condition because of high variation of elevation makes Nepal one of the richest countries in terms of hydro power potential. Despite the vast amount of sources, not all have been used in Nepal. Many small to large scale private-run and Government owned companies operate their hydropower projects throughout Nepal. This study is to assess the run of river hydropower potential of the Karnali Basin by using GIS (Geographical Information System) and Continuous Semi-distributed Hydrological Model (Hydrological Modeling System – HMS). The digital Elevation model (DEM) is used to calculate the elevation data of upstream and downstream ends of the reaches and daily discharges of the reaches are derived from precipitation data using HEC-HMS model with Nash efficiency ranging from 61.7% to 82.02 % and the volume deviation -1.52 % to 17.3 % for calibration and validation period. Using design discharge corresponding to 40th percentile flow with the hydraulic head, total power potential of 14150.80 MW is determined. Key words: Hydropower, GIS (Geographical information system), DEM (Digital elevation model), percentile _____________________________________________________________________________________ INTRODUCTION Water resources are the most important natural resources because they are not only renewable natural resources but also abundantly available in Nepal. A favorable topographic condition because of high variation of elevation (from less than 100m to 8848 m) makes Nepal one of the richest countries in terms of hydro power potential. Hydropower is the major source of electricity in this country. World’s 20% of the electricity is produced by Hydropower. In contrary, 96 % of electricity in Nepal is generated by Hydropower [1]. That says a lot of Nature Power of Nepal. Hydropower electricity is environment friendly as it does not cause in pollution of the air or the land and is also the most efficient method of all. Even though Nepal is rich in water resources, we are only able to utilize about one and half percentage of our hydropower potential until now. In Nepal, electricity is available to limited percentage of people in urban and semi-urban areas. Hence, most Nepalese living in villages uses firewood for their energy requirements. On the other hand, the growing industrial sector needs reliable energy supply, which can only be fulfilled by hydropower in the country like Nepal. Purpose of Research Despite the vast amount of sources, not all have been used in Nepal. Many small to large scale private-run and Government owned companies operate their hydropower projects throughout Nepal. Due to insufficient amount of electricity available, many parts of Nepal share the amount of electricity that is available to them. Medium Hydropower Study Project (MHSP), Nepal Electricity Authority (NEA) conducted a Screening and Ranking study of various identified hydropower projects ranging from 10 to 300MW capacity for major basins of Nepal. The project reported the total installed capacity of 138 projects as 9,613MW before fine screening and ranking study [2]. Under the power system master plan project, NEA conducted the feasibility study of