Ground Water: Strategic or Emergency Reserve

Abstract

Ground water in Brazil is progressively being exploited to supply cities and urban centers, as well as for industries, irrigation and tourism. It is estimated that there are 416 thousand wells in the country, with an annual increase of 10.8 thousand new wells being drilled, meeting the needs of 30–40 % of the population. This exploited volume is still small when compared to the potentials of their renewable reserves of 42,000 m3 s−1. Despite its considerable contribution to the social economic development of several regions of the country, and its ecological role in maintaining the base flow of water bodies, management of ground water is still incipient and does not reflect its current and strategic importance. The lack of public policies reflects the current lack of information regarding the total amount of water being used from aquifers, as well as the lack of knowledge regarding the risks of anthropogenic contamination to which they are subjected, and which affect water quality. The water matrix of the country does not contemplate this resource in a correct way, and therefore loses opportunities of using it efficiently. If water were used correctly, cost could be lowered regarding installation and operation of supply systems, in addition to protecting the water in issues related to climatic changes. Challenges for adequate managements include: (a) discipline of ground water use; (b) protection of aquifers and catchment with regards to anthropogenic contamination; and (c) establish technical solutions for an integrated and efficient use of surface and ground water.