Sewer Sediment Gate and Vacuum Flushing:
Laboratory Flume Studies

Chi-Yuan Fan, Qizhong Guo, Ramjee Raghaven, and Richard Field

To be presented at the 3^rd International Symposium on Environmental Hydraulics,

Tempe, Arizona, USA, December 5-8, 2001. 

Abstract

The objective of this study was to test the performance of a traditional gate-flushing device and a newly-designed vacuum-flushing device in removing sediments from combined sewers and CSO storage tanks. A laboratory hydraulic flume was used to simulate a reach of sewer or storage tank. The flushing device was fabricated and installed at the head-end of the flume. The removed sediments were collected at the end of the flume and weighed. The test results indicate that the vacuum-flushing device is slightly more efficient than the gate-flushing device; the weight of flushed sediments increases with the initial water volume in the flushing device; the weight of flushed sediments decreases with the initial water depth in the flume; the weight of flushed sediments only changes slightly with the size of flushing device opening for water release and does not necessarily increase with the size.