Development of Optimization Model for River Dredging Management Using MCDA

The main purpose of this study is to develop an optimal river dredging management model by applying MCDA (Multi-Criteria Decision Analysis) technique specifically in Korea where river dredging research are scarce. This model supports the decision making by providing weight factors covering dredging cost, and social and environmental impacts. This model requires various input data which are dredging points, dredging machines, dewatering machines, disposal sites. Furthermore, for the model development, the researcher applied imaginary dredging project area for model assessment and analysis. We used a total of 5 cases of weight factors combination. It can classify weight factors combination in 2 categories. The first category is weight factors combination for single-objective optimization and another category is weight factors combination for multi-objective optimization. The single-objective optimization is same that one weight factor is 1.0 and other weight factor is 0.0. The multi-objective optimization is used equality weight factors combination or weight factors from previous study. According to model simulation, it shows that cost of dredging is different approximately 18% due to weight factors. Besides, the maximum cost is obtained when weight factor of social impact is 1.0. In contrast, minimum cost of dredging projects is discovered when weight factor of cost is 1.0. From the weight factors in previous study, it illustrates that there are about 2% beyond the minimum cost of dredging projects, and approximately 18% less than maximum cost. Next study will be used real river dredging areas or simulation results of bed changes. The results of this study can be efficiently applied to 4 major rivers in Korea where periodical river dredging is necessary.