Comparison of Nonlinear Reservoir and UH Algorithms for the Hydrological Modeling of a Real Urban Catchment with EPASWMM

This paper presents a comparative analysis of two hydrological models in the Storm Water Management Model (SWMM) software, namely, non-linear reservoir (N-LR) and unit hydrograph (UH), on urban catchment Cascina Scala, Pavia Italy. The were applied for simulation rainfall-runoff transformation 42 sub-catchments while flow routing underground channels was simulated by means De Saint-Venant equations. A dataset rainfall runoff 14 events from 2000 to 2003 adopted calibration validation models. performed 7 out maximizing fit modeled-to-measured hydrographs final channel system. Prediction performance assessed through different indices. Results both measured data well terms total hydrograph. Whereas time peak reliably predicted models, N-LR found slightly outperform UH volume prediction, though it requires more detailed knowledge system its implementation. Accordingly, must be preferred case scarcity data.