OPTIMIZATION OF A DETENTION BASIN USING AN ANALYTICAL HYDROLOGICAL MODEL

Detention basins are major drainage works used for downstream flood attenuation. However, it has been noticed that the models used to determine their placements and dimensions require the analysis of a large number of factors and scenarios, which, when not correctly oriented, means that the optimal solution might not be found. A recently proposed analytical approach to the modeling of detention basins associated both in series and parallel, allows the determination of their optimal configuration through an algebraic method. Such approach is based on the linear system theory and the instantaneous unit hydrograph. The flood peak to attenuate was calculated by two of the most widely used models: Storm Water Management Model (SWMM) and Analysis of Complex Watersheds (ABC6). A case study was carried out in the Taboão detention basin, located in the channel Córrego Taboão, which is part of the Alto Tietê watershed. Such detention basin is located in the metropolitan region of São Paulo. Using this analytical approach, it was possible to analyze a wide variety of scenarios and to determine the optimal solution in a more continuous way when compared to the other models mentioned. This study demonstrated that this approach is promising for the design and analysis of complex watersheds, due to its ability to represent it with less data and in a more direct and elegant manner.