Estimation of Water Resources Availability and Mini-Hydro Productivity in High-Altitude Scarcely-Gauged Watershed

Streamflow prediction in high-altitude scarcely-gauged catchments is essential for efficient water resources management and hydropower generation. Aim of this study is to estimate water resources availability (WRA) by the application of a standard rainfall-runoff model and to study its impact on mini-hydropower production with application to Mangla basin. The Mangla basin is a scarcely gauged catchment situated in the snow- and glacier-fed Himalayan and Pir Panjal Range. Daily streamflow forecasting has been performed by the application of a GIS (Geographic Information System) based hydrological modeling system (HEC-HMS) with observed and TRMM (Tropical Rainfall Measuring Mission) rainfall data to cover the ungauged part of the catchment. The obtained results suggest that HEC-HMS can efficiently reproduce daily streamflows in snow-fed glacierized catchments with Nash-Sutcliffe (NS) coefficients in the range 0.71–0.80. The WRA was estimated at the Mangla dam to analyze its impact on mini-hydropower generation at Upper Jhelum Canal (UJC). The gross mini-hydropower potential energy on the UJC was found to be 196 and 360 GWH for average and design discharge, respectively, demonstrated that mini-hydro power generation could be a significant addition for the energy sector of Pakistan.