Separation of Flood Plain Flow: 1-D Momentum Equation Solver

Abstract

A floodplain is an area of land close to a stream or river that extends from its banks to the valley walls or high mountains surrounding it. It is frequently inundated during periods of high runoff. Along with the main stream, a large volume of flow passes through this floodplain during flood discharge. The term "floodplain flow" refers to this redundant discharge. When studying the hydro-morphodynamics of a river from bank to bank, it is necessary to understand the flow distribution throughout the main stream and flood plain. The main stream's water level and discharge are critical parameters for estimating river bank erosion. As a result, the floodplain may operate as a sediment sink during periods of high flow. River hydraulic and hydrodynamic processes are intricate. There are numerous river modeling tools and approaches available for evaluating the distribution and generation of river flow over floodplain and main-stream. This study examines such two methods for generating river flow over the flood plain and in the main stream. The approaches involve the use of a one-dimensional momentum equation and a two-dimensional modeling tool (Mike21C) to generate main-stream and flood plain flow. The Kalni-Kushiyara river is chosen as a case study in order to determine its validity.