Analyses of Poções and Camalaú weirs after São Francisco’s river transposition using morphological process on Sentinel 2 orbital images

Brazil suffers from the constant season drought, mainly in the northeast, directly affecting the water supply. Therefore, studies on the causes, effects and solutions have been developed and becoming of great importance for society. The São Francisco river transposition was designed to mitigate the drought supplying weirs along its course. Among them are Poções and Camalaú, located respectively in Monteiro and Camalaú in Paraíba state. In this sense, the paper aims to evaluate the temporal effect of drought on the Poções and Camalaú. Remote sensing images, obtained by Sentinel-2 satellite in four different dates, were used with digital image processing techniques to detect weir's area. Therefore, it was possible to verify the occurrence of a considerable increase of the area and, consequently, of the volume of water after during the first three years of the transposition. However, after a problem with the transposition, a drastic decrease in the flooded area of both weirs occurs. The paper presented an efficient use of digital image processing and Sentinel-2 images to perform a temporal evaluation of flood areas.