Identificação e avaliação de pontos de alagamentos nos bairros Petrópolis e Ribeira na cidade de Natal/RN com suporte de geotecnologias

Abstract

Urban flooding are frequent in Brazilian cities due to soil sealing caused by the disorderly urbanization of cities, the occurrence of extreme precipitation events and failures in the urban drainage system. In the city of Natal/RN, the traditional neighborhoods of Ribeira and Petrópolis have flood points that cause socioeconomic and health disorders to the population. Thus, this study aims to identify and evaluate areas susceptible to flooding in these neighborhoods based on the use of geotechnologies. For this purpose, data on land use and cover, urban drainage system and topographic data provided by public agencies were integrated into the Geographic Information System (GIS) environment. In this way, ground control bases obtained in loco with the Global Navigation Satellite System (GNSS) were used to guarantee data with better precision to generate the Digital Terrain Model (MDT) and the Digital Surface Model (MDS) that allow the identification of topographical depressions and determination of the direction of surface flow of rainwater. The results showed the occurrence of eight depressions, among which six with historical occurrence of flooding and surface flow confluence, in addition to revealing that the rainwater drainage system is poorly distributed and/or in precarious conditions in six topographical depressions. Therefore, these areas around the topographical depressions are areas of high susceptibility to flooding in the study area.