ABSTRACT: Presented hydrograph separation principle is based on several exponential and linear equation members superposition. It describes the quantitative behaviour (discharge) of hydrologic system (catchment) or aquifer (spring) by set of unique, constant values of starting discharges Q0, as well as set of unique recession coefficients (? or ß) for each detected flow component. The main idea behind the method is based on a simplified understanding of reality: the same discharge should reflect the same water saturation (piezometric) level in the system. Hence, the separation method requires detailed recession curve studies of each hydrologic/aquifer system to create really representative, mathematically described master recession curve. In the process of hydrograph separation, each measured discharge value is understood as a result of superposition of one or several laminar flow components (exponential sub-regimes) and eventually also turbulent ones, expressed by linear equation members. Every measured discharge value Qt is then determined just by a representative time t – theoretically elapsed time from the overall maximum discharge value Qmax. Subsequently, amounts discharged in different flow components can be calculated using the t value in their individual equations. As the exponential equation has no analytical solution, each discharge value Qt has to be solved by iteration process.