VERIFICATION OF EMPIRICAL FORMULAS FOR CALCULATING MEAN LOW FLOW WITH THE VIEW TO EVALUATING AVAILABLE WATER RESOURCES

Aim of the study In the present study, we aimed to verify empirical formulas for calculating mean low flow (MLF) with the view to evaluating available water resources for mountain catchments, located in the upper Vistula Basin. The following empirical formulas were analysed: Punzet and Stachý. Material and methods The studies were conducted in the following stages: analysis of significant trends for low flows in the analysed catchments, followed by the mean low flows determination using the analysed methods, and the determination of available water resources in relation to MLF obtained from the various analysed methods. Results and conclusions The analysis of the results showed lack of statistically significant trends in the course of low flows for the analysed catchments. Also, the analysis indicated significant differences between MLF derived from hydrological data and that derived from empirical formulas. The obtained results indicated the need to update the empirical formulas for calculating MLF, particularly regarding the determination of available water resources in ungauged catchments, in relation to mean low flows.