The butterfly valves (3.5m diameter) of the new lock of Lanaye (Albert canal Belgium) are submitted to cavitation during the levelling. On site measurements were realised to characterize the cavitation and to optimize the opening law of the valves in order to decrease the intensity and duration of cavitation. For comparison, measurements were realised in an existing lock with similar valves which are also submitted to cavitation but don’t present any associated damages since 1960. The duration of cavitation is more or less the same for both locks, but the cavitation intensity is more important in Lanaye. To check the appearance of eventual damages, annual monitoring of the valves is realised. Some small damages were observed but the link with cavitation is not obvious. In parallel, at the laboratory, the efficiency of aeration provided around the valve is tested for different configurations. The sound and the vibrations due to cavitation are reduced when aeration is provided. Tests realised on a pipe coated with Aluminium indicates that the damages are mainly located downstream of the valve on the upper part of the pipe. These tests confirm that aeration is appropriate to reduce the damages induced by cavitation
