Abstract

This research explores the application of the Variable Parameter Kinematic Wave Numerical Model to simulate the propagation of flood waves in non-prismatic natural waterways in ungauged basins. This study addresses issues related to irregular channel boundaries and unreliable inflow data upstream and highlights impacts associated with slope variability and changes in wetted perimeter. The inflow hydrograph is evaluated by the developed study using the SCS-CN method and a quantitative approach is adopted to analyse relationships between channel characteristics and flood wave behaviour. Five hypotheses are analysed and tested to determine if variability in channel slope and variability in wetted perimeter, effectiveness of the SCS-CN method, and an integrated approach of comprehensive performance metrics all make a difference. Agreement with observed data validates that VPKWM is reliable to model flood wave propagation. The findings suggest a need for realistic representation of channel characteristics and robust validation frameworks to improve flood management practices.