Regionalization of the Q90 Steady Flows for the Japaratuba River Basin in the State of Sergipe according to its climatic regions

Abstract

The reduction and resolution of conflicts involving the use of water, as well as the guarantee of compliance with its various uses, require the appropriate management of water resources, using the instruments foreseen in the pertinent legislation. Among the legal instruments used for the distribution of water, among the different uses and users, the granting of right of use stands out, which is provided as a function of demand and water availability in the requested water body. For the establishment of water availability in a river basin it is necessary to quantify the flows, which is done from the data collected in the fluviométricas stations. However, the Brazilian hydrometric network does not fully cover all hydrography, leaving parts of it without the necessary data for the estimation of flows. The regionalization of flows has been carried out with the objective of providing hydrological information in places with no data or with little information available, as long as they share similar characteristics. The hydrographic basin of the Japaratuba River, which is the object of the study, although it has the most complete hydrological monitoring network in the State of Sergipe, is characterized by great climatic variability (Tropical Humid, Agreste and Semi-Arid), resulting in a different hydrological behavior throughout this basin. Thus, the objective of this work is to determine the regionalization equations of the Q90 residence flow for this basin, which best fit its climatic hydro behavior, in order to obtain a small variation between the actual and the calculated regionalization flow. In the determination of the Q₉₀ permanence flow, the Traditional Method of regionalization was applied, having as independent variables the drainage area of the fluviometric station and its accumulated mean precipitation. The results show that the regionalization of the permanence flow when considering the average monthly precipitation characteristics to define the homogeneous regions presented results consistent with the hydrological reality of the basin rivers and good statistical adjustments to the flows observed in the fluviometric stations.