Hydraulic Modelling of Stormwater Trashracks

Trashracks are storm water drainage structures designed to intercept litter, debris and other gross pollutants discharging into sensitive receiving waters. This paper describes the results of a series of model tests conducted at Sydney Water Board's hydraulics laboratory at Manly Vale, NSW. From the tests it was possible to identify six trash rack arrangements which were both efficient at removing litter and debris and which were also relatively self-cleaning. The six arrangements cover most site conditions, including gradual and steep channels as well as on-line and off-line trash rack configurations.