Análise comparativa da importância de vinte açudes na bacia de Sumé-PB com o emprego de métodos multicriterial e multidecisor.

Abstract

The northeastern semiarid shows an insufficient flow of river waters due to the unstable space-time rainfall and dominant geological characteristics, resulting in a dense network of temporary rivers. The solution to minimize or even to eliminate the effects of poor water resources in that region, more specifically in the town of Sume, was the construction of large, mid and small dams. However, most of them were either badly built or not used at the most of their capacity. We felt the need to make a study which could take into account the importance of the small dams in supplying water for the inhabitants of the region, the socioeconomic contributions of their construction, and the negative implications that the small dams could have. Thus, in order to evaluate the potential use of the small dams and any other information collected locally, we listed and structured hierarchically a number of socioeconomic, environmental and technical-operational aspects obtained from optimizing analyses, with the objective of evaluating their performances in a comparative way. After obtaining the preference criteria of each potential decision maker, the dams were ordered through the application of the PROMETHEE I I multicriterial method. The aggregation of the decision makers5 individual ordering was done by multideeision means of the Borda, Condorcet and Copeland methods. As expected, the dams ordering done by each decision maker was different. However, we can notice some coherence in the way the decision makers presented the criteria evaluation related to the ordering of some of the small dams in the region, especially those with the best and the worst performances. The dams performance analysis by means of multicriterial and multideeision techniques provides us with relevant information for the management of small dams in the northeastern semiarid region, where there is a critical socioeconomic situation.