A study on optimal design methodology of multi- objective rainwater detention system using SWMM and linear programming

The purpose of this study is to provide optimized design of capacity and location of multi-objective rainwater detention system which can reduce flood damage and reuse rain water by using linear programming and SWMM model. Rainwater detention system was designed with off-line method which provides excellent storage effect compared to its small capacity and 5 reserved locations of the installation were selected by using SWMM model which superposes manhole area and National Land near such area which were flooded by rainfall with the pattern of 10~30 years frequency. Construction cost, maintenance cost, reduction of water and sewage cost, cost reduction related to dam and flood damage reduction were calculated with Won unit for objective function for applying on liner programming and limiting condition were selected by considering flood discharge and area within drainage area per actual site area and return period of preliminary selected area which led to optimized design of capacity and location of rainwater detention system which can reduce the cost. The result of this study, rainwater detention system can be installed in order to reduce the flood damage and effectively utilize the rain water and by adding geological features, cost and benefit items can be applied on the flood damage reduction plan.