Case Study:Two-Dimensional Model Simulation of Channel Migration Processes in the West Jordan River, Utah

A depth-averaged, two-dimensional model was applied to simulate the migration processes of a meandering reach in the West Jordan River in the state of Utah, USA. The sediment continuity equation was solved to determine the rate of bed degradation and aggradation. The rate of bank erosion is calculated by determining bed degradation, lateral erosion, and bank failure. Because bank material in the West Jordan River is stratified with layers of cohesive and non-cohesive materials, a specific bank erosion model was developed to consider stratified layers in the bank surface. This bank erosion model distinguishes itself from other models by relating bank erosion rate with not only flow but also sediment transport near the bank. Additionally, bank height, slope, and thickness of each layer in the bank surface were considered when calculating the rate of bank erosion. The developed model was applied to simulate the processes of meandering migration in the West Jordan River between 1981 and 1992. Historical real-time hydrographic data, as well as field survey data for channel geometry and bed and bank materials, were used as the input data. Simulated cross-sectional geometries after this 12-year period were compared with field measurements, and qualitative and quantitative agreements were reached.