This study aims to understand the governing processes and quantify sediment connectivity at catchment and reach scales, and relation with riverbank erosion that affect morphodynamics in semi-arid river systems. As the morphodynamics of the catchment and river network system of reach levels are complicated system and demanding high input data, this study will apply reduced complexity approaches of GIS, connectivity index , and simplified models (e.g, CASCADE, CAESAR-Lisflood) using satellite images, archives and global available datasets, and flume experiment will apply to test the relation between sediment connectivity and bank erosion in response to key drivers.