As indicators of bedload transport, hydrophone measurements have been performed in the Erlenbach stream since 1986. Analysis of the data shows that the total number of hydrophone impulses for several flood events is proportional to the sediment volume accumulated in the retention basin below the measuring site. A relationship also exists between the hydrophone activity and the runoff volume of the flood events. Looking at a shorter time scale, the number of hydrophone impulses per minute varies considerably for a given flow rate, which seems to be characteristic for the pulsing nature of bedload transport. A seasonal variation is observed for both the threshold discharge for the beginning of transport and for the transported sediment volume.