Comparisons between Methodologies for Estimating minimum reference flows used in Granting Grant

Abstract

The State Water Resources Policy aims to ensure control, for current and future users, of water use and its use in satisfactory quantity, quality and regime. Current legislation provides, as one of the instruments for managing water resources, the granting of the right to use water to its holder for a pre-established period and in a personal and non-transferable manner. As only part of the minimum reference flows can be granted, there is a limitation on the use of water. In periods of lower water availability, it is necessary to analyze the influence of the seasonality of flows in the criteria for granting water use, creating alternatives for the management of water resources. In this context, the present work was carried out with the objective of evaluating and comparing the minimum reference flows and verifying the possibility of an increase in water availability for different users. Data from five fluviometric stations of the Alto Iguaçu and Ribeira watersheds, both located in the state of Paraná, were used, comparing values required by current legislation with those obtained by methodologies used mainly in the United States and Europe Method, Q_7,10Tennant Method, Wet Perimeter Method. The results obtained allowed us to state that the minimum reference flows can be adjusted since the methodologies applied to the same fluviometric stations result in different values for the minimum reference flows.