|The shape causes rapidly flowing water to form a vortex which forces the larger, heavier particles are outwards and downwards into a lower chamber. Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber||*[http://www.conteches.com/Products/Stormwater-Management/Treatment/CDS.aspx CDS]*[https://www.hydro-int.com/en/products/downstream-defender Downstream defender]*[http://nextstorm.ca/sdd/ SDD]
|The shape causes rapidly flowing water to form a vortex which forces the larger, heavier particles are outwards and downwards into a lower chamber. Floating debris, oils and grease are trapped behind a baffle or in small tank area, towards the top of the main vortex chamber|