Hydrograph separation and flow analysis by specific electrical conductance of water

The use of the specific electrical conductance of water to separate flow hydrographs into event (new) and pre-event (old) waters has been studied through the analysis of background events and flow process phenomena in a study basin. Runoff ratio analysis shows that background events, such as periods of no rainfall or no flow, influence the percentage of old water occurring in the hydrograph. Comparison of one result with a separation using δ 18O as tracer shows that the separation model of Matsubayashi et al. (1991) produces reasonable results. The analysis of the conductance-discharge ( C- Q) relationship showed that there were fast flows in a majority of the wet season hydrographs.