In the river Mosel, a hydroelectric plant is situated near the city of Koblenz. Alongside the plant, a fish passage is present. The presence of the fish passage results in an extra channel through which river discharge can be transported. The Bundesanstalt für Wasserbau (BAW) has requested Aqua Vision to quantify the discharges in the fish passage and in the channels connected to the fish passage. In July 2015 and March 2016, Aqua Vision has deployed three horizontal ADCPs over a three day period at fixed locations in the fish passage. A large number of calibration transects have carried out by use of two StreamPro ADCPs.