Simulation of operation of detention tanks

The performance of detention tanks with different characteristics (volume, on-line and off-line arrangement) has been evaluated according to the results of a continuous simulation.The conceptual simplified model for sewer system simulation (COSMOSS) model has beenused to simulate the operation of the tanks.The differences between the performance of on-line and off-line tanks and theinfluence of the characteristics of different catchments have been examined.According to the results of the simulations detention tanks demonstrated goodperformances in total suspended solids retention and this evenience can certainly helpto prevent water pollution of receiving water bodies in urban areas, even if the differencesbetween the catchments, especially regard to the first flush effect, influence theperformance of the tanks. Anyway considerable good efficiencies can be obtained withtank volumes of about 30–50m3/haimp, in terms of number, maximum concentrations andduration of overflows, generally not guaranteed only with overflow devices.