Geotecnologia aplicada à análise da potencialidade do reúso de efluentes provenientes de estações de tratamento de esgoto: o estudo de caso da região hidrográfica Lagos São João, RJ

Abstract

Water is a vital resource, scarce in many regions, which justifies the search for more modern and sustainable management of water resources, which increases water security and rationalization of use, among them the reuse of effluents from Sewage Treatment Plants (STPs). Due to the exponential growth in water demand combined with the low availability of water sources, the Lagos São João Hydrographic Region (RH VI) of the State of Rio de Janeiro (ERJ) is one of those with the greatest water insecurity in ERJ, which has increased in recent years with population growth and reached a critical state in the summer of 2023/2024. The main objective of this research is to apply geotechnology to evaluate the potential for reusing effluents generated in STPs as an alternative source of supply for non-potable demands. For this purpose, this work uses geoprocessing techniques to perform spatial analysis. The specific objectives are: a) to map consumers with water collection permits in the region; b) map potential water suppliers for reuse; c) identify attributes to be used in geotechnology to perform spatial analyses; and d) evaluate the supply potential through heat maps. To achieve these objectives, data were collected from the 11 Sewage Treatment Plants (STPs) located in RH VI. The following parameters were considered for analysis: a) collection permits and corresponding flows of potential consumers; b) flow of STPs; and c) distances from STPs to potential consumers. The data were analyzed using geotechnology and the reuse potential was evaluated by correlating the flows of the respective STPs with the distances to consumers. It was possible to identify STPs with the greatest potential for supplying water for reuse, due to geographic restrictions, especially in relation to the availability of treated flow and its distance to relevant consumer centers. Thus, this work contributes to water security in RH VI.