Assessment of Rainfall-Runoff Models for Flood River Extreme Event Simulations (PAP014409)
José Guimarães de Carvalho Neto, ALFREDO RIBEIRO NETO, Suzana Maria Gico Lima Montenegro
Flood forecasting and early warning systems
Floods are characterized by a rapid runoff response to the rainfall. In many cases, due tothe fast response time, it is difficult to provide alerts and to establish the actions needed to remove thepopulation from risk sites. The objective of this study is to analyze the performance of three hydrologicalmodels, HEC-HMS (Hydrologic Engineering Center - Hydrologic Modeling System), MGB-IPH model(Large Basins Hydrological Model) and MODAHC (the acronym from Portuguese ?Self CalibratedHydrological Model?) in order to determine which model has the best performance in the simulation of theextreme flood events in the Una River basin in the State of Pernambuco. The analysis will help choosingthe hydrological model more adequate to be used in the operation of a flood warning system in the State.The selection of the hydrological models pursuit to take into account the distinct characteristics and thedifferent ways of parameterization. This will provide an accurate analysis of the extreme events simulationperformance. MODHAC is a rainfall-runoff lumped model. The HEC-HMS is distributed by sub-basinsdeveloped in HEC-USACE. The MGB-IPH is distributed by cell and it has been widely applied in largebasins in Brazil. The simulations have been accomplished at five streamgauges for extreme eventsoccurred in 2000, 2004 and 2005. The models analysis were performed using graphs and statisticalcriteria such as relative peak discharge error, volume error, standard deviation, mean absolute error, rootmean square error, Nash-Sutcliffe coefficient and coefficient of determination. MODHAC had moredifficulty to represent the streamflow in the study area, hence the MGB-IPH and HEC-HMS achievedgood results and similar performance. One factor in favor of the HEC-HMS model is the facility ofimplementation and integration with the hydrodynamic model HEC-RAS.