Department Sanitation, Water and Solid Waste for Development

Science-based policy recommendations for non-sewered sanitation in urban areas

Recent scientific evidence is shaping best practices for non-sewered sanitation (NSS). 

Explore four policy recommendations in this Policy Brief

Extbase Variable Dump
array(2 items)
   publications => '33030,32131' (11 chars)
   libraryUrl => '' (0 chars)
Extbase Variable Dump
array(2 items)
   0 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=33030, pid=124)
      originalId => protected33030 (integer)
      authors => protected'Strande, L.' (16 chars)
      title => protected'Integrating recent scientific advances to enhance non-sewered sanitation in 
         urban areas' (87 chars)
      journal => protected'Nature Water' (12 chars)
      year => protected2024 (integer)
      volume => protected2 (integer)
      issue => protected'5' (1 chars)
      startpage => protected'405' (3 chars)
      otherpage => protected'418' (3 chars)
      categories => protected'' (0 chars)
      description => protected'Half of the world’s population is now served by non-sewered sanitation, ye
         t the field remains fragmented, with a focus on individual research agendas,
          and prevalence of imprecise terminology that hinders scientific learnings a
         nd leads to misconceptions. The field is at a decisive juncture, with scient
         ific knowledge taking off that holds the potential to fulfil the urgent need
          for inclusive sanitation in a rapidly urbanizing world. In this critical Re
         view, relevant and diverse research results are assembled with findings tran
         slated to one consistent terminology, to provide scientific evidence to draw
          out interlinkages and learnings, debunk common misconceptions and identify 
         key research needs. Properties of non-sewered wastewater are highly variable
         , and degradation during storage has a direct impact on greenhouse gas emiss
         ions and downstream treatment processes, which facilitate different resource
          recovery. New technologies and wastewater-based epidemiology can help to ad
         dress the lack of monitoring. The findings are presented by wastewater prope
         rties, biological processes during storage, treatment processes and monitori
         ng.' (1143 chars)
      serialnumber => protected'' (0 chars)
      doi => protected'10.1038/s44221-024-00240-7' (26 chars)
      uid => protected33030 (integer)
      _localizedUid => protected33030 (integer)modified
      _languageUid => protectedNULL
      _versionedUid => protected33030 (integer)modified
      pid => protected124 (integer)
   1 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=32131, pid=124)
      originalId => protected32131 (integer)
      authors => protected'Strande, L.; Evans, B.; von Sperling, M.; Bartram, J.; H
         arada, H.; Nakagiri, A.; Nguyen, V.-A.' (129 chars)
      title => protected'Urban sanitation: new terminology for globally relevant solutions?' (66 chars)
      journal => protected'Environmental Science and Technology' (36 chars)
      year => protected2023 (integer)
      volume => protected57 (integer)
      issue => protected'42' (2 chars)
      startpage => protected'15771' (5 chars)
      otherpage => protected'15779' (5 chars)
      categories => protected'city-wide inclusive sanitation; fecal sludge; onsite; septic tank; pit latri
         ne; sewer; sustainable development goals; wastewater' (128 chars)
      description => protected'Progress toward Sustainable Development Goals for global access to safe sani
         tation is lagging significantly. In this Feature, we propose that misleading
          terminology leads to errors of categorization and hinders progress toward s
         anitation service provision in urban areas. Binary classifications such as "
         offsite/onsite" and "sewered/nonsewered" do not capture the need for "transp
         ort to treatment" or the complexity of urban sanitation and should be discar
         ded. "Fecal sludge management" is used only in the development context of lo
         w- or middle-income countries, implying separate solutions for "poor" or "so
         uthern" contexts, which is unhelpful. Terminology alone does not solve probl
         ems, but rather than using outdated or "special" terminology, we argue that 
         a robust terminology that is globally relevant across low-, middle-, and upp
         er-income contexts is required to overcome increasingly unhelpful assumption
         s and stereotypes. The use of accurate, technically robust vocabulary and de
         finitions can improve decisions about management and selection of treatment,
          promote a circular economy, provide a basis for evidence-based science and 
         technology research, and lead to critical shifts and transformations to set 
         policy goals around truly safely managed sanitation. In this Feature, the th
         ree current modes of sanitation are defined, examples of misconceptions base
         d on existing terminology are presented, and a new terminology for collectio
         n and conveyance is proposed: (I) fully road transported, (II) source-separa
         ted mixed transport, (III) mixed transport, and (IV) fully pipe transported.' (1596 chars)
      serialnumber => protected'0013-936X' (9 chars)
      doi => protected'10.1021/acs.est.3c04431' (23 chars)
      uid => protected32131 (integer)
      _localizedUid => protected32131 (integer)modified
      _languageUid => protectedNULL
      _versionedUid => protected32131 (integer)modified
      pid => protected124 (integer)

Integrating recent scientific advances to enhance non-sewered sanitation in urban areas

Half of the world’s population is now served by non-sewered sanitation, yet the field remains fragmented, with a focus on individual research agendas, and prevalence of imprecise terminology that hinders scientific learnings and leads to misconceptions. The field is at a decisive juncture, with scientific knowledge taking off that holds the potential to fulfil the urgent need for inclusive sanitation in a rapidly urbanizing world. In this critical Review, relevant and diverse research results are assembled with findings translated to one consistent terminology, to provide scientific evidence to draw out interlinkages and learnings, debunk common misconceptions and identify key research needs. Properties of non-sewered wastewater are highly variable, and degradation during storage has a direct impact on greenhouse gas emissions and downstream treatment processes, which facilitate different resource recovery. New technologies and wastewater-based epidemiology can help to address the lack of monitoring. The findings are presented by wastewater properties, biological processes during storage, treatment processes and monitoring.
Strande, L. (2024) Integrating recent scientific advances to enhance non-sewered sanitation in urban areas, Nature Water, 2(5), 405-418, doi:10.1038/s44221-024-00240-7, Institutional Repository

Urban sanitation: new terminology for globally relevant solutions?

Progress toward Sustainable Development Goals for global access to safe sanitation is lagging significantly. In this Feature, we propose that misleading terminology leads to errors of categorization and hinders progress toward sanitation service provision in urban areas. Binary classifications such as "offsite/onsite" and "sewered/nonsewered" do not capture the need for "transport to treatment" or the complexity of urban sanitation and should be discarded. "Fecal sludge management" is used only in the development context of low- or middle-income countries, implying separate solutions for "poor" or "southern" contexts, which is unhelpful. Terminology alone does not solve problems, but rather than using outdated or "special" terminology, we argue that a robust terminology that is globally relevant across low-, middle-, and upper-income contexts is required to overcome increasingly unhelpful assumptions and stereotypes. The use of accurate, technically robust vocabulary and definitions can improve decisions about management and selection of treatment, promote a circular economy, provide a basis for evidence-based science and technology research, and lead to critical shifts and transformations to set policy goals around truly safely managed sanitation. In this Feature, the three current modes of sanitation are defined, examples of misconceptions based on existing terminology are presented, and a new terminology for collection and conveyance is proposed: (I) fully road transported, (II) source-separated mixed transport, (III) mixed transport, and (IV) fully pipe transported.
Strande, L.; Evans, B.; von Sperling, M.; Bartram, J.; Harada, H.; Nakagiri, A.; Nguyen, V.-A. (2023) Urban sanitation: new terminology for globally relevant solutions?, Environmental Science and Technology, 57(42), 15771-15779, doi:10.1021/acs.est.3c04431, Institutional Repository

Faecal Sludge Management: Systems Approach for Implementation and Operation

This book compiles the current state of knowledge of the rapidly evolving FSM sector, and presents an integrated approach that includes technology, management and planning. Available as a free download in English, Spanish, and French. You can access the book by clicking <<here>>.

Faecal Sludge Management: Highlights and Exercises

This book is an update of the technical aspects of the book: ‘Faecal Sludge Management: Systems Approach for Implementation and Operation’. Available as a free download in English, you can access it by clicking here.

Methods for Faecal Sludge Analysis

This book provides a basis for standardized methods for the analysis of faecal sludge and the role it plays in Citywide Inclusive Sanitation (CWIS). You can access the book by clicking here.

General FSM

Faecal Sludge Treatment Technologies

Resource Recovery from Treatment

Coming soon!

  • Optimal operating conditions for faecal sludge pyrolysis.
    Gold, M., Bleuler, M., Cunningham, M., Arnheiter, R., Schönborn, A., Niwagaba, C., Strande, L.
  • To char or not to char? Review of technologies to produce solid fuels for resource recovery from faecal sludge.
    Andriessen, N., Ward, B.J., Strande, L.

Market Driven Approach to Treatment Products

Faecal sludge Quantities and Qualities (Q&Q)

Coming soon!

  • Quantities and Qualities (Q&Q) of Faecal Sludge for Planning and Management.
    Strande, L., Englund, M., Carbajal, J.P.
    In preparation as a chapter of "Methods for Faecal Sludge Analyses" (IWA publication)
    Velkushanova, K., Strande, L., Ronteltap, M., Koottatep, T., Brdjanovic. D., Buckley, C. (book editors)
  • Modeling of faecal sludge quantities and qualities for resource efficient and accurate design of management and treatment solutions.
    Englund, M., Carbajal, J.P., Bassan, M., Ferré, A., Vu, T.H.A., Nguyen, V.A., Strande, L.
Extbase Variable Dump
array(2 items)
   publications => '30343' (5 chars)
   libraryUrl => '' (0 chars)
Extbase Variable Dump
array(1 item)
   0 => Snowflake\Publications\Domain\Model\Publicationprototypepersistent entity (uid=30343, pid=124)
      originalId => protected30343 (integer)
      authors => protected'Andriessen,&nbsp;N.; Appiah-Effah,&nbsp;E.; Browne,&nbsp;S.&nbsp;J.&nbsp;I.;
          al Jahjah,&nbsp;R.; Kabika,&nbsp;J.; Kinobe,&nbsp;J.&nbsp;R.; Korir,&nbsp;N
         .; Nishimwe,&nbsp;P.; Niwagaba,&nbsp;C.&nbsp;B.; Pradeep,&nbsp;R.; Prasad,&n
         bsp;P.; Tembo,&nbsp;J.&nbsp;M.; William,&nbsp;A.; Ambuehl,&nbsp;B.; Strande,
         &nbsp;L.' (312 chars)
      title => protected'Quantities and qualities of fecal sludge: experiences from field implementat
         ion with a Volaser in 7 countries during a pandemic' (127 chars)
      journal => protected'Frontiers in Water' (18 chars)
      year => protected2023 (integer)
      volume => protected5 (integer)
      issue => protected'' (0 chars)
      startpage => protected'1130081 (14 pp.)' (16 chars)
      otherpage => protected'' (0 chars)
      categories => protected'accumulation rate; characteristics; statistical relations; standardized appr
         oaches; distance sensor; fecal sludge' (113 chars)
      description => protected'Reasonable estimates for quantities and qualities (Q&amp;Q) of fecal sludge 
         that accumulate in onsite sanitation containments are fundamental for the de
         sign of appropriate management and treatment solutions, from community to ci
         ty-scale. There are increasing attempts to improve Q&amp;Q estimates, but cu
         rrent approaches are still at a conceptual level, and are not yet standardiz
         ed with confirmed statistical relationships. To reach this level, we will ne
         ed consistent approaches for planning, measuring, and global collaborations.
          Hence, the objectives of this study were: (1) to assess and compare Q&amp;Q
          of fecal sludge from seven cities and communities, and explore statistical 
         relationships that could be used to increase accuracy of Q&amp;Q estimations
         ; (2) to test and launch the Volaser device for measuring <em>in situ</em> v
         olumes of fecal sludge; and (3) to capture lessons learned from field implem
         entation with collaborators in seven countries during a global pandemic when
          no international travel was possible. The study took place in Ghana, India,
          Lebanon, Kenya, Sierra Leone, Uganda, and Zambia during the COVID-19 pandem
         ic. Q&amp;Qs were measured in 204 containments with a Volaser, laboratory an
         alysis, and questionnaire. Results indicate that there are differences in To
         tal Solids (TS) and Chemical Oxygen Demand (COD) in fecal sludge based on co
         ntainment type, toilet type, source, and whether there is a water connection
          on the premises. Based on the results of this study, together with previous
         ly published open-source data, an empirical relationship for Volatile Solids
          (VS) and TS of 0.49 (<em>R</em><sup>2</sup> = 0.88) was established using 1
         ,206 data points. For COD/TS, no significant relationship was observed. Deve
         loping such empirical relationships will be useful for planning and modeling
          approaches. An external evaluation was conducted to evaluate overall projec
         t management, Volaser technology transfer, and effects of collaborating duri
         ng the COVID-19 pandemic...' (2450 chars)
      serialnumber => protected'' (0 chars)
      doi => protected'10.3389/frwa.2023.1130081' (25 chars)
      uid => protected30343 (integer)
      _localizedUid => protected30343 (integer)modified
      _languageUid => protectedNULL
      _versionedUid => protected30343 (integer)modified
      pid => protected124 (integer)

Quantities and qualities of fecal sludge: experiences from field implementation with a Volaser in 7 countries during a pandemic

Reasonable estimates for quantities and qualities (Q&Q) of fecal sludge that accumulate in onsite sanitation containments are fundamental for the design of appropriate management and treatment solutions, from community to city-scale. There are increasing attempts to improve Q&Q estimates, but current approaches are still at a conceptual level, and are not yet standardized with confirmed statistical relationships. To reach this level, we will need consistent approaches for planning, measuring, and global collaborations. Hence, the objectives of this study were: (1) to assess and compare Q&Q of fecal sludge from seven cities and communities, and explore statistical relationships that could be used to increase accuracy of Q&Q estimations; (2) to test and launch the Volaser device for measuring in situ volumes of fecal sludge; and (3) to capture lessons learned from field implementation with collaborators in seven countries during a global pandemic when no international travel was possible. The study took place in Ghana, India, Lebanon, Kenya, Sierra Leone, Uganda, and Zambia during the COVID-19 pandemic. Q&Qs were measured in 204 containments with a Volaser, laboratory analysis, and questionnaire. Results indicate that there are differences in Total Solids (TS) and Chemical Oxygen Demand (COD) in fecal sludge based on containment type, toilet type, source, and whether there is a water connection on the premises. Based on the results of this study, together with previously published open-source data, an empirical relationship for Volatile Solids (VS) and TS of 0.49 (R2 = 0.88) was established using 1,206 data points. For COD/TS, no significant relationship was observed. Developing such empirical relationships will be useful for planning and modeling approaches. An external evaluation was conducted to evaluate overall project management, Volaser technology transfer, and effects of collaborating during the COVID-19 pandemic. Success factors for collaborating with new and existing partners without face-to-face meetings included laboratory capacity and experience with analytical methods, study objectives that were relevant for the partner and locality, and a strong quality assurance plan to ensure comparability of results. The lessons learned can be taken forward as ways to reduce carbon footprint, and contribute to resilient, inclusive development research projects.
Andriessen, N.; Appiah-Effah, E.; Browne, S. J. I.; al Jahjah, R.; Kabika, J.; Kinobe, J. R.; Korir, N.; Nishimwe, P.; Niwagaba, C. B.; Pradeep, R.; Prasad, P.; Tembo, J. M.; William, A.; Ambuehl, B.; Strande, L. (2023) Quantities and qualities of fecal sludge: experiences from field implementation with a Volaser in 7 countries during a pandemic, Frontiers in Water, 5, 1130081 (14 pp.), doi:10.3389/frwa.2023.1130081, Institutional Repository

Laboratory methods

Sustainable Implementation/Capacity development

Education Material

Faecal Sludge Management Workshop

FSM Highlights and Exercises

SFD (Shit Flow Diagram) for seven cities in Africa and Asia

Eawag/Sandec FSM Publications PRE-2010

Journals and Conference papers

Design considerations and constraints in applying on-farm wastewater treatment for urban agriculture. 4th SWITCH Scientific Meeting. IWMI, Eawag-Sandec.
P. Reymond, O. Cofie, D. Koné (2009). Keywords: Wastewater treatment, Urban agriculture, Participatory action research, Water quality, Ghana

Influence of sand layer depth and percolate impounding regime on nitrogen transformation in vertical-flow constructed wetlands treating faecal sludge
A. Panuvatvanich, T. Koottatep, D. Kone (2009) . Keywords: Denitrification, Faecal sludge treatment, Impounding regime, Nitrification, Vertical-flow constructed wetlands

Hydraulic behaviour of vertical-flow constructed wetland under different operating conditions. A. Panuvatvanich, T. Koottatep, D. Kone (2009). Keywords: Constructed wetland, Drainage pattern, Feeding pattern, Hydraulic behaviour, Tracer study

Improving Environmental Sanitation, Health, and Well-Being: A Conceptual Framework for Integral Interventions. H. Nguyen-Viet, J. Zinsstag, R. Schertenleib, C. Zurbrügg, B. Obrist (2009). Keywords: Integrated approach, Health, Environmental sanitation, MFA, QMRA, Social sciences

Co-composting of faecal sludge and organic solid waste for agriculture: Process dynamics. O. Cofie, D. Kone, S. Rothenberger, D. Moser (2009). Keywords: Excreta, Feacal sludge, Solid waste, Co-composting, Compost quality, Nutrients

Recovery of Biosolids from Constructed Wetlands Used for Faecal Sludge Dewatering in Tropical Regions. I.M. Kengne, A. Akoa, D. Kone (2009). Keywords: Faecal sludge, Dewatering, Biosolids, Recovery, Constructed wetlands

Vertical-flow constructed wetlands as sustainable sanitation approach for faecal sludge dewatering in developing countries. I.M. Kengne, P.H. Dodane, A. Akoa, D. Kone (2009). Keywords: Echinochloa pyramidalis, Biosolids, Developing countries, Faecal sludge, Sustainable approach, Vertical-flow constructed wetlands

An approach to optimise nutrient management in environmental sanitation systems despite limited data. A. Montangero, H. Belevi (2008). Keywords: Environmental sanitation, Developing countries, Material flow analysis, Nutrient recovery, Phosphorus, Data scarcity, Data uncertainty, Plausibility assessment

Effects of faecal sludge application on growth characteristics and chemical composition of Echinochloa pyramidalis (Lam.) Hitch. and Chase and Cyperus papyrus L. I.M. Kengne, A. Akoa, E.K. Soh, V. Tsama, M.M. Ngoutane, P.H. Dodane, D. Kone (2008). Keywords: Antelope grass, Constructed wetlands, Cyperus papyrus, Echinochloa pyramidalis, Faecal sludge, Growth characteristics, Nutrient contents, Planted drying beds, Sludge dewatering beds, Vertical-flow constructed wetlands

Optimising water and phosphorus management in the urban environmental sanitation system of Hanoi, Vietnam. A. Montangero, L.N. Cau, N.V. Anh, V.D. Tuan (2007). Keywords: Environmental sanitation, Material flow analysis, Phosphorus, Nutrient recovery, Hanoi, Developing countries

Assessing nutrient flows in septic tanks by eliciting expert judgement: A promising method in the context of developing countries. A. Montangero, H. Belevi (2007). Keywords: On-site sanitation systems, Nutrient, Material flow analysis, Developing countries, Data scarcity, Expert knowledge

Helminth eggs inactivation efficiency by faecal sludge dewatering and co-composting in tropical climates. D. Kone, O. Cofie, C. Zurbrügg, K. Gallizzi, D. Moser, S. Drescher, M. Strauss (2007). Keywords: Ascaris, Co-composting, Drying beds, Faecal sludge, Helminth eggs, Trichuris

Investigating helminth eggs and Salmonella sp. in stabilization ponds treating septage. G. Sanguinetti, C. Tortul, M.C. Garcìa, A. Montangero, M. Strauss (2004). Keywords: Ascaris, Biosolids, Helminth eggs inactivation, Primary ponds, Salmonella, Septage

The challenge of faecal sludge management in urban areas – strategies, regulations and treatment options. A.M. Ingallinella, G. Sanguinetti, T. Koottatep, A. Montagnero, M. Strauss (2001). Keywords: Faecal sludge, Hygienic quality, Septage, Sludge, Standards, Treatment

Cotreatment of sewage and septage in waste stabilization ponds. A.M. Ingallinella, G. Sanguinetti, R.G. Fernandez, M. Strauss, A. Montangero (2000). Keywords: Effluent quality, Septage, Sewage, Sludge, Waste stabilization ponds, Vacuum trucks

Solids separation and pond systems for the treatment of fecal sludges in the tropics - lessons learnt and recommendations for preliminary design. SANDEC Report No. 5/98. U. Heinss, S.A. Larmie, M. Strauss (1998).

Treatment of sludges from on-site sanitation - Low cost options. M. Strauss, S.A. Larmie, U. Heinss  (1997).

Project Reports, Guidelines, Manuals and Articles

EWM articles in the Sandec News

Urine Treatment

Videos

Video Recording of 3rd international Faecal Sludge Management Conference 2015 (FSM3) in Hanoi, Vietnam (Kopie 1)