Water evaporation reduction: case study in São Gonçalo reservoir/PB

Abstract

Climate changes have provided a worsening of the management of water resources in semiarid regions. Disputes over the various uses of water cause conflicts between users and high evaporation rates, present in these regions,contribute significantly to the worsening of water crisis. The reduction of evaporation rates in reservoirs in these regions appears as another way to increase the supply of water, through of different techniques application, using different materials, each one adapted to the specific case. The study aims to analyze the reduction of water evaporation in the reservoir of São Gonçalo, PB in the northeastern semiarid from the use of various techniques suggested in the literature. It was realized simulations with four different techniques of evaporation reduction in the São Gonçalo reservoir, located in the semi-arid region of Paraiba State. The results showed that the use of polyethylene balls presented the best evaporation reduction index, however its use is recommended when the reservoir presents low levels of water volumedue to its higher implementation and maintenance cost.The wind breaking technique showed a satisfactory evaporation reduction indexbeing recommended for the study region due to its low implementation and maintenance cost, not causing impacts to the water body. However, further studies have to be conducted, aiming the identification of possible environmental impacts not only in the water body, but in the region surrounding the reservoir.