KfW’s Sanitation Portfolio in SSA – an appropriate mix

							KfW’s Sanitation Portfolio in SSA –
an appropriate mix of sustainable technical
options
AfricaSan + 5 Conference, Durban, 18-20 February 2008




Dr. Uwe Stoll
Alexander Grieb                           Senior Technical Adviser
                                          KfW Development Bank
Background

     All 82 ongoing KfW water sector projects in
       Sub-Sahara Africa address sanitation issues

     24 projects comprise specific sanitation
       investment with
          EUR 80 Mio German financial contribution
          3 Mio beneficiaries
          Burkina Faso, Burundi,
           DR Congo, Eritrea, Ethiopia, Kenya,
           Mali, Malawi, Tanzania, Uganda, Zambia
          10 centralized systems,
            5 on-site solutions,
            9 projects combining central, semi-central
           and on-site system


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Principles of sustainable sanitation

     Human Health

                                           Sustainable           Health
     Affordability (especially poor       Environment         Awareness
       households)

     Environmental sustainability
                                           Sustainable         Affordable
                                           Institutions        Solutions
     Institutional sustainability


            Appropriate technical solutions considering
             the physical environment as well as socio-cultural conditions

       Necessary standard: level of health and environmental risks
       Problem: not all available technical solutions are known to all stakeholders

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Applied Sanitation Systems of today



                                             ECO-Water Cycle for
    On Site Systems    •Central Sewerage                           ECOSAN
                                             Central Sewerage
    • Latrine          • Piped Sewerage      • Piped Sewerage      • Segregation
    • VIP              • WWTP                • WWTP
    • Compost Toilet   •Discharge                                  • Closed-Loop
                                             • Effluent Reuse




    Rural Areas        Urban                 Urban                 Rural and
    Semi-urban         Semi-urban            Semi-urban            Urban
    Settlements        Settlement            Settlements           Settlements


                         Level of user participation
         high                 low                      low             high
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Sanitation Arrangements:
Centralized / off-site sanitation

     Collection by conventional sewerage:
         applicable in city centres and commercial/industrial areas
     Collection by simplified or settled sewerage:
        20-50% of cost for conventional sewerage, but: if not properly constructed,
          higher risk of blockage and non-functionality
     Major advantage: transport of sewage out of populated areas
     Crucial aspects: pipe material, implementation of house connections,
       transport by gravity or pumps, water flow/quantity

     Treatment: Process natural (ponds, wetlands, etc) or
       technical (activated sludge, trickling filters)
         Important: extent of treatment, disposal and reuse


     Operation and maintenance mainly assured by professional operator

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Sanitation Arrangements:
Semi-centralized and
decentralized / on-site sanitation

    Semi-centralized sanitation: sewerage and treatment systems
     Option for urban quarters, e.g peri-urban areas, rapidly growing cities

    Decentralized / on-site sanitation (“improved sanitation”):
        Rural areas, less densely populated (peri-)urban areas, slums
     Dry systems: Sanplat, VIP, VIDP, Blair latrine; EcoSan with urine
      separation (Skyloo, Composting toilet) or w/o urine separation (ArborLoo,
      Fossa alterna)
     Wet systems: Pour-flush toilet, Aqua-privy and soakaway, septic tank
      system, anaerobic filter
       can be scaled-up to (semi-)centralized systems
     Communal toilets
     Biogas generators

    O&M on site by users, emptying & transport by public/private companies
       public hygiene also depending on private commitment
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Disposal of effluent and excreta
Aim: prevention of health hazards and pollution of receiving water
   bodies and soils, valorisation of nutrients if feasible
 Safe reuse or disposal of effluent and sludge: to be assessed right from
   beginning of planning process

Centralized systems:
 Treated wastewater: Reuse in agriculture, water reclamation,
  disposal in surface water bodies or groundwater,
 Sludge: reuse of sludge in agriculture, land reclamation,
  use as fuel in power plants/cement industry,                 Major concern
  disposal on landfills, incineration                           Regular
                                                               emptying of
Decentralized systems:                                         pits/septic tanks
 Wet/dry systems: reuse/disposal on site, emptying/reuse      distance to
   of sludge in agriculture, disposal on dumpsite              potential reuse
 EcoSan: Reuse of urine / sludge or compost                   location
 Greywater reuse
                                                               Hygienic risks
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Identification of
appropriate sanitation solutions
Basic Planning Criteria:
  Population density, socio-economic environment, urban development,
  water supply level, existing facilities, legal/institutional conditions,
  hydro-geological conditions, topography, receiving body, reuse potentials,
  investment and running costs,
  acceptance by users.


 Objective: Mix of sanitation options
    for best value for money

      Participation of target group


     Individual instead of standard solution



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Identification by unit cost
    Assessing specific cost
                                                                                  Problem of cost
                        Type                       Relative        Relative
                                              construction costs   O&M costs
                                                                                  comparison:
                                                 (per person)      (per person)
          On-Site                                                                  Local
    dry   Ordinary pit latrine with sanplat           1                 1
                                                                                  variations in
                                                                                  physical and
                     VIP latrine                     1-2                1
                                                                                  socio-cultural
            Compost latrine with urine               1-2               1-3
                 separation
                                                                                  landscape
    wet    Pour-flush toilet with lined pit          1-2               2-3
                                                                                   Designed to
            Septic tank with soakaway              3-5(-20)            2-3
                                                                                  same overall
          Off-site Centralised /Semi-centralised                                  standards?
                Full flush toilet with            10-35(-60)            10
           Settled/Simplified sewerage
                  Full flush toilet                 20-70              10
          (with conventional sewerage).


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Consequences
for project preparation
  All possible arrangements to be considered
   at planning stage
  Allocation of sufficient resources
   for the identification process

 Least-Cost-Solution dependant on
  Design horizon
  Realistic extrapolations and assumptions
  Level of technology
  Concept for treatment and disposal/reuse
  Construction and material
  Participation of beneficiaries

  Phased implementation of sanitation options
     with scaling-up possibilities

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Conclusion: essential aspects for an
appropriate mix of sanitation options

  Thorough assessment of the actual situation –
     socio-cultural, socio-economical, institutional, … and technical

  Realistic assumptions on the future development (urban development,
     population growth, standards of living, institutional framework,… )

  Comprehensive knowledge about the existing technologies for on-site and
     off-site sanitation for collection, transport and disposal/reuse

  Selection of the least-cost-solution with the appropriate mix of technical
     arrangements – affordable and manageable for users and service provider


 Crucial for sustainable technical             Identifying sustainable sanitation
 solution:                                     solutions not only a matter of
 professional know-how on each                 cost and “software”, but also of
 level and acceptance of users                 sound technical arrangement
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 Thank you for your attention




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