Hydrologic system response models for hilly sub-catchments of a river

Focusing on the development of geomorphologic instantaneous unit hydrographs (GIUH), this study presents a method to predict direct runoff hydrographs for two hilly sub-watersheds in Uttarakhand, India. Utilizing kinematic-wave theory and Horton’s stream-order-law ratios, the research analytically determines travel times for overland and stream flows. A two-parameter Gamma-type model enhances GIUH development, which is validated against observed storm event data. Its reliance on geomorphologic parameters allows for application in ungauged or partially gauged hilly watersheds with good accuracy.