Assessment of water volumes granted and water availability in the Azul River basin, Paraná, Brazil

Water plays a crucial role in various activities concerning a watershed. However, the unregulated utilization of water resources and the absence of effective management can jeopardize the diverse uses of water, turning a particular region into a critical area. Therefore, the aim of this study was to conduct a comprehensive analysis of water demands in relation to water availability in the Azul River Watershed, Paraná state, Brazil. To achieve this objective, data on licenses for water resources use issued by the state regulatory agency have been utilized, and the study area was defined using geographic coordinates. By segmenting the hydrographic unit, it is possible to identify different types of water uses (consumptive and non-consumptive), permitted water outflows, specific purposes, and water users. Furthermore, an examination of the conflicts between demand and water availability was also conducted. The findings revealed that the agricultural sector accounted for the highest water withdrawals, with the greatest number of active permits. Additionally, regarding consumptive uses, aquaculture emerged as the largest consumer of water, accounting for 62% of the total water consumption. The water demand of users in the Rio Azul basin cannot be achieved considering the current licensing criteria. This indicates that water resource management requires special attention to the relationship between demand and water availability.