Feasibility assessment of SHP potential using GIS-enhanced RS approach in poorly gauged river basin in Nigeria

Abstract

• Combination of Remote Sensing, Geographic Information System and Natural Resources Conservation Service – Curve Number model is helpful in effective planning and management of watershed in the absence of information on hydrological, topographical and geological characteristics • Run of river (ROR) hydropower plants , utilizing instantaneous river flow were suggested for the identified sites in the study area. • 11 points out of the 58 points examine at 2 km interval were classified as a feasible potential site for hydropower development . In this paper, we present the result obtained by application of Remote Sensing (RS) data & Geographic Information System (GIS) procedure in the identification and selection of feasible sites for small hydropower (SHP) projects in Oyanmi River in the Benin-Owena drainage Basin in Nigeria, using Natural Resource Conservation Service-Curve Number (NRCS-CN) model. Catchment delineation, Sub-basin Area size, slope, Curve Number (CN), Land Use Land Cover (LULC), Digital Elevation Model (DEM), rainfall intensity, etc. were obtained by RS and Arc GIS tools. Data on rainfall were obtained from Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) for the year 2018 and validated using Nigerian Meteorological Services Agency (NIMET) Lokoja synoptic station data and then utilized for the computation of simulated discharge. The simulated discharge were correlated with observed data obtained from a gauging station in the study area. The correlation between observed and simulated data yielded a good correlation result of 65% and 63% for rainfall and discharge respectively with good statistical significance P-value. Elevation values extracted from the DEM were used in calculating the available head utilized in evaluating the hydropower potentials across the 58 hydrometric mapped-out points. Based on the criteria that a viable SHP should have a minimum slope of 2% and 10 m available head, 11 points were identified in Oyanmi sub-basin with feasible power potential ranging from 393.849 kW to 16038.194 kW at 92% annual flow exceedance which if developed would improve access to energy and socio-economic development of the study area.