This paper reports the development of an enhanced two-dimensional (2D) numerical model for the simulation of flow
hydrodynamics and mass transport in meandering channels. The hydrodynamic model is based on the solution of the depth-averaged flow
continuity and momentum equations where the density of flow varies with the concentration of transported mass. The governing equation
for mass transport model is the depth-averaged convection and diffusion equation. The dispersion terms arisen from the integration of the
product of the discrepancy between the mean and the actual vertical velocity distribution were included in the momentum equations to
take into account the effect of secondary current. Two laboratory experimental cases, flow in mildly and sharply curved channels, were
selected to test the hydrodynamic model. The comparison of the simulated velocity and water surface elevation with the measurements
indicated that the inclusion of the dispersion terms has improved the simulation results. A laboratory experiment study of dye spreading
in a sine-generated channel, in which dye was released at the inner bank, centerline, and outer bank, respectively, was chosen to verify the
mass transport model. The simulated concentration field indicated that the Schmidt number can be used as a calibration parameter when
dispersion is computed using a 2D approach with a simplified turbulence model.