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Simplified Sewerage
Microsoft Producer presentations

Simplified sewerage collage


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Part 1     Transcript of Part 1 (includes slides)

Part 2     Transcript of Part 2 (includes slides)

Part 3     Transcript of Part 3 (includes slides)

Part 4
    Transcript of Part 4 (includes slides)

Presentation downloads


                 
           Supporting material:

               Simplified Sewerage Design Manual  (University of Leeds, 2001)
 

     Simplified Sewerage: Design Guidelines (World Bank, 1994)

               The Design of Shallow Sewer Systems [shallow sewerage = simplified sewerage]
               (UNCHS, 1987)

               Simplified sewerage: a mature and essential sanitation technology (IWA, 2004)

     Sewerage: a return to basics to benefit the poor (Proceedings of the Institution of Civil 
     Engineers − Municipal Engineer
, 2008)

               Simplified sewerage can be cheaper than on-site sanitation
               
see: Simplified sewerage: fiinancial cost advantages

             Report cover

The Experience of Condominial Water and Sewerage Systems in Brazil  (by José Carlos Melo, WSP, 2005)
       
See also: Water tariff structures − these are important if people are charged for sewerage services as a percentage of their water bill. For conventional sewerage this is typically 100%, but for simplified sewerage it should be lower − for example, in Natal in northeast Brazil, where simplified sewerage was first implemented in the early 1980s, the surcharge was 40% (currently − January 2008 − it is 35%: details here).

               Scaling-up using condominial technology (Waterlines, 2006)

     Can sewerage be pro-poor? Lessons from Dakar (IRC, 2009)

Can numerical computer modelling aid innovation, efficiency and cost reduction in sanitation provision? (Desalination, 2009) – excerpt from Abstract: “Analysis of a simplified sewerage installation using the building drainage numerical model ‘DRAINET’ confirms that this sanitation option is best suited to densely populated areas, while it is also shown that its implementation may be expanded to less densely populated areas by a reduction in pipe diameter from 100 mm to 75 mm set at a shallow slope characteristic of simplified sewerage installations.”  

               Condominial Sewerage Systems for the Federal District of Brazil (CAESB, 1998):
                       Part 1   Part 2   Part 3   Part 4
    
The Brasília experience is very pertinent: CAESB (the Water & Sanitation Company for Brasília and the Federal District) first tried simplified sewerage in its poor periurban areas − it worked well and CAESB then asked “If it works well in poor areas, why shouldn’t it work equally well in non-poor areas?”.  They tried it and it did.  The next question is: If simplified sewerage works well in both poor and non-poor urban areas, should we ever even think about using conventional sewerage in residential urban areas? Answer: No.

Video: Women’s Voices (GWA, 2005) – this film shows the experience of a community in establishing simplified sewerage systems with a gender focus in periurban areas of Cali, Colombia.

Sewerage: shallow systems offer hope to slums (World Water, 1985)
− includes a description of the strictly Brazilian-style simplified sewerage scheme installed in a low-income area on the outskirts of Karachi where some 27 litres of water per person per day was obtained from public standpipes, showing that on-plot water connections are not necessary for simplified sewerage to work well. The cost? Only USD 45, which included the squat pan and trap, grit and grease trap, house connection, street laterals, collector main and primary treatment. 

Low-cost sewerage (Dialogue on Diarrhoea, 1992)

Book: Low-cost Sewerage (1996) [slightly strange page-by-page html format]

Putting Participation in Context: An Evaluation of Urban Sanitation in Brazil (PhD dissertation, Stanford University, 2004 − abstract)

Community participation in urban sanitation: experiences in northeastern Brazil (Journal of Planning Education and Research, 2007)

Multistakeholder Evaluation of Condominial Sewer Services (American Journal of Evaluation, 2005)

               PROSANEAR: People, Poverty and Pipes (World Bank, 1998)

                   Community Participation and Low Cost Technology: Bringing Water Supply and Sanitation
               to Brazil's Urban Poor (World Bank, 2006)

               Lower Costs with Higher Benefits: Water and Sewerage Services for Low-income Households −
               Lessons from EAPP [the El Alto Pilot Project in La Paz, Bolivia] (WSP, 2007)

               Good Sewers Cheap? Agency-Customer Interactions in Low-cost Urban Sanitation in Brazil
              (World Bank, 1995)
             

               Access to Water Supply and Sanitation in Brazil: Historical and Current Reflections; Future
               Perspectives  (UNDP HDR 2006 Thematic Paper)  

                    Lessons and Experiences from the eThekwini Pilot Shallow Sewer Study [Executive Summary]
               [Shallow sewerage = simplified sewerage]  See also listing of  Reports and video below.

               Durban Metro Water: Private Sector Partnerships to Serve the Poor (WSP, 2001)

                    Ericson, Nebraska: Flat Grade Sewers (NSFC, 1987)

     Sewerage Works – Public investment in sewers saves lives (PSIRU, 2008) 

               India: Simplified Sewerage – An appropriate option for rapid sanitation coverage in urban areas
               (
Foundation for Greentech Environmental Systems, 2008) reported costs are one third of those
               for conventional sewerage.

               A simple aid for designing sewers (J.CIWEM, 1996)

    ►Tractive force design for sanitary sewer self-cleansing (Journal of Environmental Engineering, 2009)

               A model for the movement of large solids in small sewers (WST, 2005)
               
 
               Forces on sanitary solids in small sewers (WST, 2005)

     Effect of biofilm formation on roughness coefficient and solids deposition in small-diameter PVC
     sewer pipes (JEE ASCE, 2007)



Selection of sustainable sanitation arrangements (Water Policy, 2007)

Quote:
“We argue that other sanitation arrangements may be as ‘ecological’ as “EcoSan”.[*] For example, the sanitation system comprising either conventional or low-cost sewerage (i.e., the conveyance of yellow, brown and grey waters together in the same sewer system), followed by wastewater treatment to produce both biogas and a microbiologically safe effluent, and reuse of the effluent in aquaculture and/or agriculture [*] (or for the irrigation of urban green space or forests), is equally ‘ecological’."

*See:  Ecological Sanitation   Wastewater use in Agriculture   Wastewater Use in Aquaculture
 

 
               Simplified sewerage can be used in villages as well as in periurban and urban
               areas: for example, in rural Ceará in northeast Brazil − read this excerpt  from
               Dr Sarmento’s PhD thesis (next link)
.
                 
               PhD thesis
               
Low-cost Sanitation Improvements in Poor Communities: Conditions for Physical Sustainability
               (Dr Verônica Sarmento, 2001) [Includes appraisal of condominial sewerage systems in Brazil]      

               Video (.wmv format)
               The Durban Shallow Sewer Pilot Study [shallow sewerage = simplified sewerage]
               Courtesy of the Water Research Commission, South Africa

      See also:  Community-based Sewerage in Asia − it’s almost, but not quite,
      Brazilian-style simplified sewerage.

      History:  Backyard tubular drainagein Victorian England in 1852 − remarkably similar
      to Brazilian-style simplified sewerage.


Simplified sewerage is often the institutionally most appropriate option for large-scale application in poor urban/periurban areas

Simplified sewerage was accepted by the Brazilian State Water and Sewerage Companies precisely because it was a sewerage system and one that was introduced (in fact, in 1986) into the national sewerage design code [for further details see Microsoft Producer presentation #4 above]. Moreover their engineers could readily understand its hydraulic design basis [see Microsoft Producer presentations #1−3 above] since it is very similar to that used for conventional sewerage. In contrast the Brazilian State Water and Sewerage Companies have absolutely ‘nothing to do with’ on-site sanitation systems as they regard their provision to be solely a municipal responsibility.

There are a few situations when you wouldn’t use simplified sewerage − details here Otherwise simplified sewerage is one of the best things since

Sliced bread



    See also: Low-cost combined sewerage

    Water, Sanitary and Waste Services for Buildings, 5th ed. (Butterworth-Heinemann, 2002) − free
    download here.

    Conventional sewerage (for comparison) (US EPA Fact Sheets)
        Conventional Gravity Sewers
        Sewer Cleaning and Inspection
        Sewers − Lift Stations
    See also: Sewer design: the costs of conservatism (eWISA, South Africa 1998)