Aquifer is a large underground water reservoir located hundreds of meters deep. Research indicates that the Brazilian territory is home to 27 aquifers, the largest in extension and volume of water being the Guarani Aquifer.
With about 1.2 million square kilometers, the Guarani Aquifer it is present in four South American countries: Argentina, Brazil, Paraguay and Uruguay. Approximately 70% of this water reservoir is located in Brazil, spread across the subsoil of Mato Grosso, Mato Grosso do Sul, Goiás, Minas Gerais, São Paulo, Paraná, Rio Grande do Sul and Santa Catherine.
The geological structure of the region that encompasses the Guarani Aquifer is responsible for storing water underground. This area is formed by sedimentary rocks, a lot of sand and little clay, characteristics that facilitate absorption of rainwater, which, after being absorbed, is confined in impermeable rocks hundreds of meters from depth.
The exact amount of water stored in this aquifer remains to be clarified. However, estimates point to an average of approximately 40 trillion cubic meters. This potential is exploited through the drilling of more than a thousand wells with depths of 100 to 300 meters, providing water to thousands of people in the country.
Despite the importance of the Guarani Aquifer, human activities, especially industrial and agricultural, have caused water contamination. The biggest villains in this process are the pesticides used in agriculture and the vinasse (a residue from the fractional distillation of sugarcane), which reach the reservoir.
In order to use the water from the aquifer in a sustainable and planned manner, the Guarani Aquifer System Environmental Protection and Sustainable Development Project is being developed. This project, developed jointly by Argentina, Brazil, Paraguay and Uruguay, aims at the rational use of water and the preservation of the Guarani Aquifer.
By Wagner de Cerqueira and Francisco
Graduated in Geography
Brazil School Team
Source: Brazil School - https://brasilescola.uol.com.br/brasil/aquifero-guarani.htm