A harmony-based calibration tool for urban drainage systems

The US Environmental Protection Agency's storm water management model SWMM 5.1 is widely used to simulate urban drainage processes both for qualitative and quantitative analysis. In the present work, SWMM 5.1 was applied to the Fossolo urban sub-catchment in Bologna, Italy, and the geographic information system ArcGIS was adopted to reproduce the spatial distribution of rainfall. An innovative and original optimisation procedure was developed, coupling the jazz-music-based harmony search evolutionary algorithm with SWMM 5.1 for the estimation of runoff parameters. Seven historical storm events were taken into account for model calibration and validation. A careful sensitivity analysis highlighted the effectiveness of the calibrated parameters for simulations. The results obtained showed the proposed approach to be a useful tool for the calibration of hydrological parameters in large urban drainage systems, defining a satisfactory correlation between modelled and measured data.