Avaliação da vulnerabilidade natural à contaminação das águas subterrâneas no Município de Caetité-BA

Abstract

The increase in the standard of living and the growth of the population imply an increase in the number of houses built, the opening of new roads, and other infrastructure works that involve moving earth. By removing the layer of natural vegetation from the soil to carry out these services, man provides an increase in erosive processes, reduces the portion of rainwater that infiltrates the soil, and promotes changes in the hydrological cycle in the urban environment, reflected in the increase in flow rates and volumes of surface runoff, which increases the risk of flooding. As is the case in other municipalities in Brazil, Cruz das Almas, in the State of Bahia, has been included in the implementation of works by the Federal Government aimed at meeting the demand for housing of social interest, as is the case with the implementation of Residencial Jardim Imbira I and II, located at km 225 of Rodovia Federal BR-101, in the location called Embira. This work evaluates the characteristics of the project flow for different hydrological scenarios, considering the pre-urbanization and post-urbanization phases, evaluating the possible impacts on the environment resulting from the drainage and disposal of rainwater from this housing project. The results obtained show that, considering the post-urbanization scenario, for a 53% increase in impervious area and a return period of 10 years, the project flow reaches 3.85 times the pre-urbanization conditions. Finally, it is suggested that a detention reservoir be implemented to control and dispose of additional surface runoff generated by the project's impermeable surfaces.