POTENCIALIDADES E LIMITAÇÕES DO USO DE INFORMAÇÕES ALTIMÉTRICAS PROVENIENTES DE PERFILAMENTO À LASER EM AMBIENTE URBANO

Abstract

The concentration of the Brazilian population living in urban environments requires efficiently manage the territory and the effects of water runoff, such as erosion, floods, and mass movement. This work aims to adapt the delimitation of Hydrological Sensitivity Areas (HSA) to urban areas, using the Topographic Humidity Index (TWI). The study area is the Administrative Region of São Sebastião, in the Federal District, which presents recent problems of urban expansion and urban drainage. The research discusses the potentials and limitations in the use of altimetric data from the laser profile in the derivation of digital elevation models (DEM) and the estimation of surface runoff. The application of the HSA index in urban areas requires specific methodologies: reduction of the sample point cloud by the selection of relevant factors for the flow of water, filtering of artifacts, maintenance of urban features that condition the direction of the water, elimination of vegetation cover, among others. The results obtained show the potential to establish sensitive areas within the urban network with high precision considering the influences of the local topography. Therefore, the research innovates by presenting a methodological solution to estimate HSA for the urban environment at a local scale.