Study on 1D-2D Hydraulic Modeling of a Diversion Channel on the Cavally River in Zouan-Hounien, Cote d’Ivoire

Abstract

On the Cavally River, located on the border between Côte d'Ivoire and Liberia, several hydraulic structures such as bridges and diversion channels are planned to be made in recent years in the operating perimeter of the Ity mining company. A 1D-2D hydraulic model was developed to design a diversion channel to cut a meander of the Cavally River in order to ensure hydraulic operation similar to the initial conditions of the river (water levels, flow and velocities). This model was designed with a flow rate of 240 m³/s and a Manning coefficient of 0.052 m^1/3.s^-1 for the minor bed and 0.06 m^1/3.s^-1 for the major bed. The results from the hydraulic model show that the hydraulic conditions (water levels, velocities) in the channel before and after the diversion remain almost like those of the Cavally River. Flow velocities in the Cavally River range from 0.1 to 1.6 m/s from upstream to downstream. Hydraulic conditions (water levels, flow and velocity) in the channel after diversion will remain substantially like the natural state of the watercourse. The diversion channel will therefore have no significant impact on the hydraulic operation of the Cavally River.