Project Summary

The main purpose of study is to measure amount of sewer sediments that can be removed to a designated collector upon release of water from flushing device.  In particular, a comparison is to be made between flushing efficiency of conventional gate-flushing device and that of the vacuum flushing device, EPAFLUSH^Ó, which has been recently designed by US Environmental Protection Agency.  Additional purpose of the study is to identify those hydraulic parameters that affect the flushing efficiency in order to provide guidance for field applications.

The sewer sediment flushing efficiency will be tested using a laboratory flume under various conditions. Test variables will include type of flushing device/tank, amount of water in the flushing tank, size of side opening of the flushing tank, amount of sediments initially on the bed, initial water depth above the bed sediments, and type of the sediments. Measured data will be analyzed to identify parameters that affect the flushing efficiency.

A simplified numerical model will also be developed based on mass and momentum conservation principles in order to calculate the flushing efficiency beyond the conditions that are tested in the laboratory. The measured data will be used to test the model.

Flume Testing of Sewer Sediment Flushing

Flushing Tank at Head of Flume

Sediment Collection Basket at End of Flume

Go to the flume movie