The method of Shiono and Knight [1991] is applied for predicting the lateral velocity profile averaged in depth in compound channels with high vegetation on floodplains. The model is based on the analytical solution of Navier-Stokes equations that include the effect of vegetation. The flow through vegetation was modeled by an additional term in Navier-Stokes equations for the resistance force. The coefficients characterizing the eddy viscosity and secondary flows, necessary for calculations were identified. The computational results were compared with laboratory and field measurements. The elaborated transverse velocity profiles averaged in depth and water discharges are in a good agreement with laboratory and field observations.