Análise das vazões regularizadas dos reservatórios estratégicos da Região Hidrográfica dos Sertões de Crateús a partir dos dados de diferentes estações fluviométricas

Abstract

Water resources are essential for the survival and development of a region. However, in the semi-arid zone of Ceará, the availability, quality, and sustainable management of these resources have faced increasing challenges. The Região Hidrográfica dos Sertões de Crateús (RHSC) presents high rainfall variability and high evaporation rates, requiring efficient planning to ensure water security. In this context, this study aims to analyze the regulated flows of the strategic reservoirs in the RHSC using data from two streamflow stations: Senador Pompeu (ANA Code - 36470000), located in Senador Pompeu - CE, and Fazenda Boa Esperança (ANA Code - 34750000), in Castelo do Piauí - PI. To achieve this, the monthly SMAP rainfall-runoff hydrological model was applied to calibrate station 36470000 and generate inflow series for the strategic reservoirs in the RHSC. Subsequently, these reservoirs were operated using the SIMRES software to calculate the regulated flows for reliability levels of 100%, 95%, 90%, and 80%. For station 34750000, parameters previously calibrated in other studies in the region were used. Therefore, for this station, inflows were determined and later used to calculate regulated flows following the same methodology applied to the first streamflow station. The results indicate that the regulated flow varies little across the reservoirs when switching between stations. The Carnaubal reservoir recorded the highest regulated flow for 90% reliability, with 381 L/s using data from station 36470000 and 382 L/s using data from station 34750000, showing a minimal difference of 0.3% between the two data sets. This similarity suggests that, for this specific reservoir, both streamflow stations provide comparable estimates, which may contribute to greater reliability in water resource management. Furthermore, the total regulation capacity of the reservoirs for 90% reliability was 1191.4 L/s at station 36470000 and 948 L/s at station 34750000, excluding the Fronteiras reservoir. Thus, the study highlights the need for precise calibration of hydrological models and the careful selection of historical series for efficient water resource management. The obtained results can serve as a basis for optimizing reservoir operations and minimizing the impacts of water scarcity, ensuring greater water security for the population and economic sectors dependent on water.