Prospective Water Balance Scenarios (2015–2035) for the Management of São Francisco River Basin, Eastern Brazil

Abstract

The need for renewed and healthier water resources pushes human society to develop new management procedures that warrant provisions and that are compatible with the population and economic growth. The São Francisco River is one of the main surface water resources in Brazil and is facing environmental challenges that threaten its sustainability. In the scope of growing conflicts over water resources in the São Francisco River Basin, the present research applied surface and groundwater balances for the current situation and for three prospective water demand scenarios (a pessimistic, an optimistic and an equilibrated) referring to 2025 and 2035, considering the multiple uses of the basin. For the surface water balance, the AcquaNet Decision Support System was used, whereas for the groundwater balance, the relationship between the withdrawal flow for consumptive uses and the exploitable flow was applied. The results evidenced that there are scenarios in which the available surface water resources will not be sufficient to satisfy the demanded projections. The groundwater balance was characterized as more favourable; however, the lack of knowledge creates uncertainties about these resources. Beyond its limitations, research was able to define geographical water availability and balance, allowing the indication of precise management procedures.