Uncertainty analysis of DO concentrations in the Buffalo River using the Perturbance Moment Method

Low dissolved Oxygen level is known as one of the main factors affecting the water quality in the Buffalo River today. This study is to investigate the fate and transport of DO concentrations in the Buffalo River AOC and the uncertainty of DO concentrations due to data variability and parameter uncertainty. A two-dimensional numerical WASP model is developed to simulate the fate and transport of DO concentration in the Buffalo River. Uncertainty incorporated with the model output is evaluated by using the Perturbance Moment Method (PMM). Seven uncertainty factors are considered in the uncertainty analysis, which are incoming concentration, flow, water temperature at four locations along the Buffalo River, and CBOD decay rate at 20oC. Also the effective risk of DO levels violating the selected water quality standard 5.0 mg/L is evaluated in the Buffalo River during the simulation period.