Legal protection of the Guarani aquifer in Ribeirão Preto (São Paulo State, Brasil)

Abstract

The Guarani aquifer is one of the largest reservoirs of groundwater in the world and represents a strategic reserve for the four countries of South America where it occurs: Argentina, Brazil, Paraguay and Uruguay. The municipality of Ribeirão Preto, located in the north-east region of São Paulo, with a population of over 600,000 inhabitants, is supplied entirely by water from this aquifer. Hydrogeological studies reveal the existence of a large cone of drawdown in the centre of the city due to the intensive and indiscriminate use of water pumped out by wells for decades. In rural areas, where many of the rocky outcrops of the aquifer occur and which affords direct recharge by rain water, the risk of contamination by pesticides is of some concern. Over the years the Public Ministry of São Paulo in Ribeirão Preto has provided guidelines for actions and initiatives in environmental protection, especially with regard to the Guarani aquifer. These actions and initiatives are based mainly on the principle of the supremacy of public interest over private interest and the principle of caution. On the basis of these premises the prosecutor works with the government and the private sector to monitor and remediate environmental liabilities that threaten the aquifer (landfills, diffuse contamination etc.) and to maintain due discipline within the activities that take place within the recharge zone (agriculture, industry and urbanization) including those of regulation and territorial planning.