URBAN BASIN FLOODING HAZARD MAPPING WITH LITTLE HYDROLOGICAL DATA

Abstract

Extreme rain events and unplanned cities reinforce the importance of mapping urban floods. On the other hand, spatial and meteorological data provided by government agencies are not compatible with the study of floods and thus create a scarce scenario of effectively measured data. Thus, the present work aims to map the danger of flooding for urban watershed (Rio Botas, Nova Iguaçu, Rio de Janeiro) with little data available. Mapping is performed using hydrological and hydrodynamic models. As the aforementioned basin does not have a rainfall station with a robust historical series, a methodology is implemented to select a representative station in its surroundings, which is the Ecologia Agrícola meteorological station. The rainfall regime found in the study is compatible with the Civil Defense alert scenarios, which suggests that the methodology is valid in this case. Regarding the modeling, regardless of the absence of more specific data, the result was considered satisfactory, since in the empirical validation the flooded points were the same as those presented by the Civil Defense agents. Thus, the results obtained demonstrate that it is possible to carry out a satisfactory flood mapping even in watersheds with scarcity of data.