The removal of urban litter from stormwater conduits and streams: Paper 3 - Selecting the most suitable trap

A large quantity of urban litter is finding its way into the drainage syste ms to become an eyesore and a potential health hazard. Many of the naps cur rently installed are, however, extremely ineffective at trapping and storin g urban litter. An extensive review of some 50 designs indicated that only seven showed much promise for South African conditions, although one or two other designs may be suitable for specialised installations. This paper de scribes the seven most promising options and recommends a trap selection pr ocedure. A preliminary assessment of the seven most promising trapping stru ctures concludes that three designs - two utilising declined self-cleaning screens and the other utilising suspended screens in tandem with a hydrauli cally actuated sluice gate - are likely to be the optimal choice in the maj ority of urban drainage situations in South Africa.