O conflito entre a expansão urbana e o uso da água subterrânea

Abstract

The groundwater matrix represents about 70% of the abstraction to supply the water supply system in the municipality of São José do Rio Preto. Studies carried out in 2002 showed a decay rate of the potentiometric surface of the Bauru aquifer equal to 0.15 m/year. For 2012, this value became 0.47 m/year. Reflections of this deterioration in groundwater levels are related to the growth of the urban network, linked to the increase of exploitation, and the climate changes observed over the last years. Given the above, this study aimed to evaluate the current scenario regarding the urbanization processes and the change in the rainfall regime, in order to clarify some questions regarding the city's aquifer systems. For this, the urban area was quantified and the wells were inserted in the ArcGis 10 software, with information taken from the SIAGAS database. High peripheral growth was found, where we chose to work with the region that presented the largest expansion. From the comparison between the years 2002 and 2019, the urban area of the municipality had an increase of 76%, and in the peripheral region studied, there was an increase of 697%. In 2014, rainfall reached very low levels, compared to previous years, to the detriment of the water crisis. In addition, rainfall has been decreasing over the years. Finally, the number of wells grants is increasing, while water availability has been decreasing. Thus, the system that is already in need may collapse in the very near future, compromising water supply in São José do Rio Preto.