A field experiment to evaluate the cleaning performance of sewer flushing on non-uniform sediment deposits.

The results of a field experiment to evaluate the scouring effect of a single flush operation in a compound-section sewer channel in Paris, France, are presented in this paper. Full monitoring of the experiment allowed identifying flush-related transport/deposition key processes playing a role on the evolution of the deposited sediments. Overall, the flush was able to scour sediments accumulated over the channel invert up to a significant distance from the gate. The analysis of the results revealed that the flush had a different impact on the various sediments present in the bed mixtures, with most of the eroded volume including sediment particles smaller than the median grain size.