Avaliação da qualidade da água subterrânea e superficial na região central no município de Londrina - PR

Abstract

Various liquid effluents resulting from different human activities have the capacity to contaminate groundwater and surface water, contributing to a reduction in the amount of drinking water available for human consumption. With urban sprawl resulting from the city's population growth, various land use and occupation practices in central areas have generated negative environmental impacts on different scales. Underground springs are facing increased environmental degradation, the intensity of which can vary according to the human activities carried out in the area. Given this scenario, the use of quality standards is essential for evaluating and characterizing these water sources. The aim of this study was to assess the quality of surface and groundwater in the urban center of the city of Londrina, Paraná. Groundwater samples were collected from monitoring wells, as well as water samples from the Leme stream. The samples collected were analyzed to determine the pH, total coliforms, electrical conductivity, ammonia nitrogen, nitrate, turbidity, color and total alkalinity and phosphorus present in these waters. In addition, surveys and evaluations of the local geographical aspects were of paramount importance in order to observe the influence of the urban center on the groundwater and surface water in its surroundings. Through the evaluations carried out, it was possible to observe the contamination of the waters around the areas of major urbanization. The samples had a pH of less than 6.0, indicating acidity in the water analyzed. The average pH found was 5.22, outside the standards established for Class 3 fresh waters. The presence of coliforms was found in wells P1 and P2, which did not comply with CONAMA resolution 396/2008. The presence of thermotolerant coliforms in well P1 suggests contamination by feces. High electrical conductivity values were observed in wells PM 01 and PM 02, indicating possible contamination of the water table. CONAMA Resolution 396/2008 does not set limits, but values above 100 μS/cm indicate environmental impact. Average values for ammoniacal nitrogen ranged from 0.78 to 4.72 mg/L. High concentrations of ammoniacal nitrogen indicate recent pollution by decomposing organic matter. It has been shown that urban centers have an impact on their surroundings when they are not built properly, and it is necessary to monitor the impacts caused in order to avoid possible contamination.