Sensitivity analysis of sediment resuspension parameters in coastal area of southern Lake Michigan

Model sensitivity analysis was performed to identify and compare quantitatively the important resuspension parameters in the coastal area of southern Lake Michigan. A one- dimensional resuspension and bed model capable of dealing with the type of mixed sediments ( fine- grained+ sand) common in the coastal area was developed and utilized to compare with measured suspended sediment concentrations. The results show that the most sensitive parameters in the model are the fraction of fine- grained materials and sediment availability. Other resuspension parameters such as settling velocity, critical shear stress, and erosion rate constant are also found to be important and may cause up to a 40% difference in suspended sediment concentration. Among those, the absolute magnitude of settling velocity is most crucial in controlling the first order prediction.