technical solutions for the urban poor: going to scale with ...sanitation in high-density periurban...
TRANSCRIPT
![Page 1: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/1.jpg)
This is a repository copy of Technical solutions for the urban poor: Going to scale with proven low-cost solutions.
White Rose Research Online URL for this paper:http://eprints.whiterose.ac.uk/9216/
Conference or Workshop Item:Mara, D.D. (2008) Technical solutions for the urban poor: Going to scale with proven low-cost solutions. In: AfricaSan2008, 18−20 February 2008, Durban, South Africa. (Unpublished)
[email protected]://eprints.whiterose.ac.uk/
Reuse Unless indicated otherwise, fulltext items are protected by copyright with all rights reserved. The copyright exception in section 29 of the Copyright, Designs and Patents Act 1988 allows the making of a single copy solely for the purpose of non-commercial research or private study within the limits of fair dealing. The publisher or other rights-holder may allow further reproduction and re-use of this version - refer to the White Rose Research Online record for this item. Where records identify the publisher as the copyright holder, users can verify any specific terms of use on the publisher’s website.
Takedown If you consider content in White Rose Research Online to be in breach of UK law, please notify us by emailing [email protected] including the URL of the record and the reason for the withdrawal request.
![Page 2: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/2.jpg)
![Page 3: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/3.jpg)
Duncan MaraUniversity of Leeds, UK
![Page 4: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/4.jpg)
![Page 5: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/5.jpg)
WORLD POPULATION, 1850- 2050
1850 1950 20001900 2050
Urban slum population
Urban population
Rural population
1
2
3
4
5
6
7
8
Bil
lio
ns
Year
![Page 6: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/6.jpg)
SAMJ, August 2007
CHILDREN UNDER 5Unsafe WSH responsible for
9.3% of deaths and 7.4% of disease burden
![Page 7: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/7.jpg)
Durban, 2001: Durban, 2001: AscarisAscaris in 89% and in 89% and TrichurisTrichuris in 72% of in 72% of children aged 2children aged 2 -- 10 10
living in living in ‘‘slumsslums ’’
![Page 8: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/8.jpg)
![Page 9: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/9.jpg)
![Page 10: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/10.jpg)
Per iurban areas: inadequate sanita t ionOpen storm water drains ( if there are any)
receive raw wastewater discharges
![Page 11: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/11.jpg)
Rigorous hydraulic design based on:• a minimum sewer diameter of 100 mm• a minimum tractive tension of 1 N/m 2
• a minimum value for peak wastewater flow of 1.5 litres/secondThis results in a minimum gradient of 1 in 200, and a 100 mm dia. sewer being able to serve 234 households of 5 people with a water consumption of 100 litres/ person day (or 10 people @ 50 lpd).
![Page 12: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/12.jpg)
Rigorous hydraulic design based on:• a minimum sewer diameter of 100 mm• a minimum tractive tension of 1 N/m 2
• a minimum value for peak wastewater flow of 1.5 litres/secondThis results in a minimum gradient of 1 in 200, and a 100 mm dia. sewer being able to serve 234 households of 5 people with a water consumption of 100 litres/ person day (or 10 people @ 50 lpd).
“Small flows flow better in small pipes”
![Page 13: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/13.jpg)
![Page 14: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/14.jpg)
![Page 15: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/15.jpg)
Comparative costs (1997 US$) of conventional and condominial sewerage
in Parauapebas, Pará, north Brazil
ItemConventional sewerage Condominial sewerageCondominial sewerage
Totalcost
Cost per connection
Totalcost
Cost per Cost per connectionconnection
Excavation 263,000 39 186,000 28
Inspection chambers
181,000 27 85,000 13
Sewers 185,000 28 102,000 15
Total 629,000 94 373,000 5656
Source: Melo (2005):
![Page 16: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/16.jpg)
Costs in South Africa, 2002
Sanitation technology Construction cost (ZAR)
Simplified sewerageSimplified sewerage 25002500-- 30003000
EcoSan toiletEcoSan toilet 30003000-- 40004000
Conventional sewerageConventional sewerage 60006000-- 70007000
Average exchange rates in 2002: ZAR 1000 = USD 87 = EUR 100
![Page 17: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/17.jpg)
I n this case I n this case sim p. sewerage sim p. sewerage
cheaper than cheaper than onon-- site sanitat ionsite sanitat ion
at densit ies at densit ies > ~ 160 pers/ ha> ~ 160 pers/ ha
![Page 18: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/18.jpg)
State of Rio Grande do Norte in northeast Brazil, January 2008:
Minimum water tariff: BRL 18.10 (USD 10.00)
35% surcharge for simp. sew.BRL 6.34 (USD 3.50)(1.7% of minimum wage)
Reduced min. water tariffs:
‘popular’housing:
BRL 11.51
‘social’housing: BRL 3.65
![Page 19: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/19.jpg)
No expensive manholes!
![Page 20: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/20.jpg)
![Page 21: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/21.jpg)
So on-plot water supply not essential.
![Page 22: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/22.jpg)
![Page 23: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/23.jpg)
![Page 24: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/24.jpg)
… being served w i t h s im pl i f ied sew erage
![Page 25: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/25.jpg)
CAESB, the water & sewerage company for Brasília and the Federal District, basically asked itself:
If condominial sewerage works well in poor areas, shouldn’t it also work well in non-poor areas? Answer: Yes.
The next question is:As condominial sewerage works well in both poor and non-poor areas, should we ever use conventional sewerage in urban housing areas? Answer: NO.
![Page 26: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/26.jpg)
In many cities and towns in developing countries there are some sewers and thus some local knowledge of sewerage.
Conservative engineers can accept simplified sewerage simply because it is sewerage, especially when they under-stand its rigorous hydraulic design basis
![Page 27: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/27.jpg)
If simplified sewerage, then local water & sewerage agency should interact with the beneficiary communities to inform them what is going to happen, how they should operate the system (no garbage disposal), what to do when problems occur, how much the monthly water bill would increase, and, if necessary, offer low-cost loans (to be repaid through the monthly water bill) to install household toilets – and, of course, no connection fees (too anti-poor).
![Page 28: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/28.jpg)
• Often cheaper in areas subject to annual flooding than simplified sewerage and stormwater drainage
• Good examples from small low-income coastal towns in the state of Rio de Janeiro, Brazil (where they by-pass the wastewater treatment plant during floods)
![Page 29: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/29.jpg)
Sanitation in high-density periurban areas unable to afford simplified or
low-cost combined sewerage
• By definition on-site sanitation is too expensive (simplified sewerage cheaper)
Possibly the only solution:‘SPARC-style’ community-designed, built & managed sanitation blocks
SPARC: Society for the Promotion of Area Resource Centres, an Indian NGO (www.sparcindia.org)
![Page 30: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/30.jpg)
![Page 31: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/31.jpg)
![Page 32: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/32.jpg)
Biogas generat or
![Page 33: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/33.jpg)
Biogas generat or
![Page 34: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/34.jpg)
![Page 35: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/35.jpg)
Sanitation solutions :Alternating twin-pit VIP latrinesAlternating twin-pit pour-flush toiletsUrine-diverting alternating twin-vault ventilated improved vault (VIV) latrines (“UD-VIVs” or “eThekwini latrines”)EcoSan systems - if that’s what the users want (eThekwini latrines are easily convertible to EcoSan operation)
Financing: microcredit? subsidies?
![Page 36: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/36.jpg)
![Page 37: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/37.jpg)
![Page 38: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/38.jpg)
![Page 39: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/39.jpg)
![Page 40: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/40.jpg)
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
![Page 41: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/41.jpg)
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
![Page 42: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/42.jpg)
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
![Page 43: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/43.jpg)
Are all these ‘proven low-cost’ sanitation solutions applicable at scale in Africa?
![Page 44: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/44.jpg)
• We have to get knowledge of all appropriate sanitation technologies to those in Government, but also and more importantly to those in localgovernment
• This is a MAJOR challenge for the
![Page 45: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/45.jpg)
Barbara WardBarbara Ward
![Page 46: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/46.jpg)
![Page 47: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/47.jpg)
![Page 48: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/48.jpg)
![Page 49: Technical solutions for the urban poor: Going to scale with ...Sanitation in high-density periurban areas unable to afford simplified or low-cost combined sewerage • By definition](https://reader036.vdocuments.us/reader036/viewer/2022071609/614880432918e2056c22baeb/html5/thumbnails/49.jpg)