Development of Simulation-Optimization Model for Stormwater Treatment Measure Optimization (Case Study: Gold Coast City, Australia). J. Civil Eng. Urban., 4 (3): 266-273

Urbanization and urban development builds large amounts of impervious areas, stopping the infiltrating of rainfall into soil process and consequently, requiring of the construction of large stormwater treatment measures. A new tendency in storm water management endorses ‘source control’ whereby small distributed water sensitive urban design systems are built throughout the subdivision to alleviate the effects of land use changes, and protect downstream water quality. Source control practices include use of water sensitive urban design practices like rainwater Tanks, vegetated swales, bio-retention systems, infiltration basins, and constructed wetlands in order to disconnect impervious areas from each other. These elements have different roles and costs. This paper presents a rule based method, to reduce the costs of urban stormwater management. For this purpose, two simulation and optimization model are linked together in the MatLab integrated development environment. Linking the simulation model (MUSIC) and the optimization model (Genetic Algorithm), allowed this simulation and optimization model (MUSIC-GA) to minimize the costs of various treatment devices. Results of usage of MUSIC-GA model on optimizing of urban stormwater treatment systems in about 1.7 hectares residential areas in Gold Coast City, Australia showed that optimized post development is at least 45 percent effective means for removal of pollutants from urban stormwater runoff. Also, small coefficient of variation (0.005) of the results of different runs indicated that there is a proper convergence of MUSIC-GA results toward the global optimal solution.