Module 3 The removal of urban solid waste from stormwater drains Neil Armitage Orientation

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1 Modue 3 The remova of urban soid waste from stormwater drains Nei Armitage, Department of Civi Engineering, University of Cape Town, Private Bag Rondebosch, 7701, South Africa (Armitage@ebe.uct.ac.za) Orientation We a, no doubt, recognise that urban itter in drainage systems is a probem, but what can be done about it? This is the subject of this part of the modue. The reading gives some ideas, but you shoud however be aware of a few issues: 1. Urban drainage systems fa into two categories: separated systems where stormwater and sewage is reticuated in separate reticuation systems; and combined systems where the same pipes are used for both. The report deas excusivey with the urban itter probems associated with the stormwater conduits and streams in a country where the stormwater and sewage are aways (theoreticay at any rate) separated. Where combined systems are used, much of the itter can be trapped and removed at the wastewater treatment works. On the other hand, combined sewer overfows (CSOs), which generay occur as a resut of heavy downpours, become a particuar probem as both itter and effuent ends up in the rivers. Combined sewers are something of an anathema to anyone from a water scarce region. Why woud anyone want to poute a vauabe resource stormwater with effuent?! 2. The report is ooking at trying to sove the waterborne itter probems of South Africa. South Africa is a midde income country (GDP per capita = US$5,000) with an unempoyment rate in the order of 30%. This severey imits the range of affordabe technoogies. Inevitaby, theft and vandaism are aso major probems. 3. There are two different approaches to soving the probem of waterborne itter. The first is to prevent ittering or at any rate prevent the itter from entering the drains. The second is to remove the itter once it is in the drainage system. One might say that the first is treating the cause of the probem, whist the atter is treating the symptoms! At first gance it woud seem that prevention is better than cure, but there are other considerations. Prevention means deaing with peope and some peope are difficut to dea with (particuary if they are hungry!). Remova is a technoogica probem something that engineers are generay we trained to hande. Prevention aso means deaing with diffuse sources of poution something that is never easy. Once in the drainage system, however, the itter tends to concentrate as it goes downstream (athough some of it might be eft on the banks aong the way!). This aows for economies of scae at the trapping structures. The report deas with both the aspects of prevention as we as remova, but concentrates heaviy on the atter.

2 Assignment Carry out a brief study on a densey popuated urban catchment that you are famiiar with (minimum area 1km 2 ). In no more than five pages: a) Describe the catchment (incuding topography, and-use/s, popuation distribution, income eves etc.). b) Describe the drainage system. c) Indicate the extent of the itter probem. d) Describe the existing itter contro methods. e) Indicate how effective the existing itter contro methods appear to be. f) Give your recommendations for improvement (both itter prevention and the remova of itter from the drainage system). g) Suggest how you woud finance your proposas. Additiona readings Apart from the reading The remova of urban soid waste from stormwater drains, you might ight to ook at some of the optiona additiona readings isted beow. Many of these URLs are to do with itter prevention through education. Note that education on its own cannot sove the ittering probem. Most pouters are aware that they are ittering they simpy don t care. (P.S. if you find any new sites reevant to this topic, or the addresses are no onger vaid, pease et me know). URL aw/recyc/stat/ chief eng/roadside/beautification/highway/ DESCRIPTION Foodservice & Packaging Institute, Inc About Keep America Beautifu, Inc Erie County Soid Waste District Keep Midand Beautifu Keep Nebraska Beautifu Caifornia Beverage Container Recycing and Litter Reduction Act: North Caroina Department of Transportation Anti-Litter Efforts Cean Team in Johnson City, Tn

3 98/eg/futext/sb191.htm a-sucx1.htm itter.htm d/rec Lessons/itter.htm tm /resdev.htm 7.htm okfact.htm /drainage.htm p/yarra/discussion/watermgt/discus10/four.htm ix/th47/th47a5.htm s1.htm /quaity About Keep Cincinnati Beautifu Suggestion for a aw about the Beverage Container Recycing, Leter Reduction of the State of Georgia The successfu handing of waste reduction Bandaong Foating Litter Trap In-Line Litter Separator Poutec Liter trap New ideas down the drain - Poutec itter trap) Instaation of innovative gross trap - provides a reference and a contact A new itter trap for urban drainage systems Decision-Makers Guide to Controing Litter and Iega Dumping. Waste management and ceanup cost reduction in Canada.

4 diego.ca.us/dpw/roads/adopt.htm reeases/tampa.htm homepage/teaching/661/wj661m10w00.htm htm gm.htm rong tm /RO/Latin A/Topic j.htm /Environmenta%20Education/environmenta education s1.htm t/environment.htm mw3.htm an/u1.htm ecture3.4.htm stormwater.htm wt wi.ascii Watershed Infrastructure and ecoogy program in Toronto. Storm Water Baffe Box for sediment and itter remova from storm water. Impications of urban itter in the stormwater system.

5 Hermes.ecn.purdue.edu:8001/cgi/convwqtest?gwq-016.wi.ascii Impact of first fush tanks. Steve.htm sposa backgrounder/improper.htm h.htm oups/waterways/adopt a Shore.htm m ydumping/ CSR Hydro Conduit.htm EPA 2000 Waste Prevention Litter: Peope create it Waste Prevention 2000