Recently, various researches have focused on the environmental condition assessment of oxbow lakes along rivers. In this study we investigated the bed morphology, conductivity and the changes of macro- and microelements in the oxbow, named Kacsa-tó, that was formed by the 45^th cutoff on Tisza River, then the results were plotted using GIS softwares. Our aim was to examine the specific electric conductivity and its spatial pattern at the end of the spring flood at 2013. We analyzed water samples collected by a stratified sampling system so as to conclude the extent of overturning. The inflow from the flood resulted lower conductivity values at the extensive SE part than at the distant NW part. Initially the fresh water supply from the flood does not reach the distant parts; thus, the overturning takes place more slowly so the water body replacement of the oxbow occurs constantly. Our results show that at the beginning of the flood the oxbow could be divided into two distinct heterogeneous parts. Based on the conductivity values at time of the measurement, we found that the overturning is not yet complete.