Optimal planning of decentralised storage tanks to reduce combined sewer overflow spills using particle swarm optimisation

The present study suggests an optimised method for planning multiple decentralised storage tanks which are designed to reduce combined sewer overflow (CSO) spills. Particle swarm optimisation (PSO) was applied for the optimal planning of the storage tanks in terms of location distribution and sizing. The framework for the storage optimal planning suggested in this study includes developing a simplified mathematical model that is, along with the PSO algorithm, for optimisation. In order to reduce the computational burden of PSO’s inherent iterative solution-searching process a simplified mathematical model was developed to simulate the complex hydraulic flows of a sewer network. Then, the optimisation model with the PSO algorithm was connected interactively with the mathematical model. A case study network was simulated to analyse its application in the planning of distributed CSO storage tanks, and the best available scenarios were suggested.