The AWS-Flush Sluice is used for a preventive cleaning of critical section of sewer- and combined sewer collector channels of small- and medium sizes. The AWS-Flush Sluice is installed without obstructing the flow path. By activating the impound shield of the device it impounds the upstream water. A sudden opening of the impound shield generates a strong flushing wave, moving the sedimentation and debris downstream to less critical areas. The individual programmed flushing algorithm ensures a preventive cleaning of the sewer, even at dry weather condition. Hence the hydraulic performance of the sewer lines are increased as well as unpleasant odours are avoided.