Estudo sobre ações e intervenções antrópicas de canais urbanos na Bacia do Quarenta - Manaus (AM)

Abstract

The rivers of a hydrographic basin are vulnerable to anthropic actions, mainly those found in urban areas. In this sense, the present work sought to analyze the changes in the channels of the Quarenta basin based on anthropic actions and interventions. The basin is located in the urban perimeter of the city of Manaus, thus becoming an urban basin. According to Stevaux and Latrubesse (2017), anthropic actions are divided into two forms, one indirectly and the other directly in the channel. The indirect ones are characterized as marginal occupations of rivers and works related to urban growth. On the other hand, there are anthropic interventions in the channels, executing direct engineering works. Given this, it was found that indirect actions in the Educandos-Quarenta basin were developed before the 21st century, in the occupations of the neighborhoods that make up the basin. The interventions began in 2007, with works carried out by the city hall and government of Amazonas, being entitled PROSAMIM, Social and environmental Program for Igarapés de Manaus. The works consisted of channeling, such as containment and stabilization of banks, rectification of the channel, waterproofing of the bed and, in some stretches, the coverage of the igarapé, making it submerged. Both activities were developed in the channels of the lower and middle sector of the basin. As a result, in addition to the common impacts related to occupation, interferences have potentiated impacts, such as the development of bars and technogenic deposits. At some program intervention points, the works were not efficient to withstand some extreme weather events. In certain stretches, when flooded, they compromise the urban mobility of the local population. In addition, the intervention works intend to extend to stretches in the middle and upper sectors of the basin, generating new cycles of intervention in the urban rivers of Manaus.