Avaliação do avanço da urbanização de Maceió-AL e os efeitos na hidrologia urbana de bairros que margeiam a laguna Mundaú

Abstract

Constantly in Brazil, there are reports of problems related to the inefficiency of urban planning, such as floods and landslides, which cause material and immaterial damages that are sometimes irreparable. These problems are linked, in part, to excessive and increasing urbanization processes after the second half of the 20th century; in parallel, there are many cases in which the master plans responsible for mitigating the impacts of this phenomenon prove to be ineffective and incapable of controlling risks in the urban environment. Ungoverned urbanization generates changes in hydrological, ecological and landscape characteristics in a given region - for example, there is the growth of the impermeable area, surface runoff and ecological degradation caused by changes in land use and cover. In Alagoas, the capital of the state, Maceió, is surrounded by two large water bodies, the Atlantic Ocean and the Laguna Mundaú, in the latter, there is a great density on its banks, along its entire length. This riverside occupation was not carried out in a fully planned manner, being an area susceptible to several hydrological and sanitation problems, suffering from flooding in almost every rainy event. As a mitigation, the region has several artificial microdrainage channels, which aim to stop these events, however, the transgression of the lagoon waters into the city makes them inefficient, generating overflows. In this way, the present work studied the advancement of waterproofing in this perimeter using remote sensing tools and satellite images dated from 1986 to 2016 with manipulations in QGIS and its consequent increase in the generation of surface runoff, evaluated by the SWMM software, identifying an advance in waterproofing. in the regions, but which, however, did not imply a single cause-effect relationship in the flow rate.