Sustainable sanitation recognizes that in order to be sustainable, a sanitation approach must be socially acceptable and economically viable. In this way, sustainable sanitation is a loop-based approach that differs fundamentally from the current linear concepts of wastewater management, and that does not only recognize technology, but also social, environmental and economic aspects. Sustainable sanitation is an approach that considers sanitation holistically. It recognises that human excreta and wastewater are not waste product, but a valuable resource. This view is based on the fact that wastewater and excreta contain significant amount of energy, plant nutrients and also water that can be recycled and reused, thus protecting natural resources.
On-site sanitation systems, such as pit latrines, or septic tanks etc. do form an incomplete barrier between users and the environment. Nutrients and pathogens infiltrate and contaminate water sources, hence posing a health risks. Source: CONRADIN (2007, adapted from WERNER)
Present conventional forms of wastewater management and sanitation fall either under the category of conventional waterborne or dry (pit) systems. In both cases, the design is based on the premise that excreta are waste, and that this waste should be disposed of. It is also assumed that the environment can safely assimilate this waste. These assumptions lead to linear flows of resources and wastes and often cause severe environmental pollution (see also water pollution). The technological developments that were once designed to solve the sanitation problem have become part of the problem, not the answer to it (ESREY 2000).
Linear end-of-pipe system, mixing all different kinds of wastewater. Source: WINBLAD and ESREY (2004)
In pit systems, which are abundant in many parts of the world, the toilet does form a barrier between human beings and excreta. Yet, this barrier is incomplete. Pit latrines are mostly designed to retain solids and infiltrate liquids. When liquids infiltrate, nutrients, and worse, pathogens also infiltrate. If there are large settlements, or if the toilets are built too close to water sources, this can lead to a severe pollution of ground and surface waters, as shown above. Consequences are a high prevalence of waterborne diseases.
Also conventional waterborne systems have their drawbacks. One of the largest is probably that they are linear “end-of-pipe” systems, which are constructed on the assumption that a treatment will take place at the end of the pipe. Yet, worldwide, more than 90% of the wastewater does not receive any treatment at all (CORCORAN et al. 2010), thus polluting an even larger amount of water. There are several other important drawbacks of centralised water-based sewerage (see also water pollution). Some of the most important are:
Conventional approaches to wastewater management that regard wastewater as a waste, and often are dysfunctional, have serious drawbacks. Source: CONRADIN (2010)
Sustainable sanitation aims at overcoming these drawbacks. It is not a certain technology, but an approach with certain underlying principles. There are a number of technologies (see for instance sanitation systems) that can be used to make sanitation and wastewater management more sustainable. The term “sustainable sanitation” in principle denominates the same as ecological sanitation, though the latter has a stronger focus on source separation.
The first and foremost principle is probably the one to recognise that excreta and wastewater are not a waste, but a valuable resource that can be reused and recycled. This is actually — to speak in a simplified way — the very basis of sustainability: to use resources wisely and without impairing the possibilities of future generations to meet their own needs.
Sustainable sanitation can be defined more precisely (adapted from SUSANA 2008):
The main objective of any sanitation system is to protect and promote human health by providing a clean environment and breaking the cycle of disease. In order to be sustainable a sanitation system has to do this, and additionally be economically viable, socially acceptable, and technically and institutionally appropriate, and it should also protect the environment and the natural resources. This implies the following criteria:
Most sanitation systems have been designed with these aspects in mind, but in practice they are failing far too often because some of the criteria are not met. In fact, there is probably no system that is absolutely sustainable. The concept of sustainability is more of a direction rather than a stage to reach. Nevertheless, it is crucial, that sanitation systems are evaluated carefully with regard to all dimensions of sustainability. Since there is no one-for-all sanitation solution, which fulfils the sustainability criteria in different circumstances to the same extent, this system evaluation will depend on the local framework and has to take into consideration existing environmental, technical, socio-cultural and economic conditions.
Taking into consideration the entire range of sustainability criteria, it is important to observe some basic principles when planning and implementing a sanitation system. These were already developed some years ago by a group of experts and were endorsed by the members of the Water Supply and Sanitation Collaborative Council as the “Bellagio Principles for Sustainable Sanitation” during its 5th Global Forum in November 2000 (EAWAG/SANDEC & WSSCC 2000):
To summarise, sustainable sanitation is a simple approach: the most basic principle is that it considers wastewater and excreta not as a waste, but as a resource, that sanitation has to be socially acceptable and should be as economically viable as possible. There is no “one-fits-all” approach, much rather, the most adequate solution has to be found from case to case, considering climate and water availability, agricultural practices, socio-cultural preferences, affordability, safety, and technical prerequisites — just to name a few.

CONRADIN, K. (2007): Ecological Sanitation in the Khuvsgul Area, Northern Mongolia: Socio-Cultural Parameters and Acceptance. Unpublished Master Thesis. Basel: University of Basel. URL [Accessed: 19.01.2011]. PDF
CORCORAN, E. (Editor); NELLEMANN, C. (Editor); BAKER, E. (Editor); BOS, R. (Editor); OSBORN, D. (Editor); SAVELLI, H. (Editor) (2010): Sick Water? The central role of wastewater management in sustainable development. A Rapid Response Assessment. United Nations Environment Programme (UNEP), UN-HABITAT, GRID-Arendal. URL [Accessed: 05.05.2010]. PDF
EAWAG (Editor); SANDEC (Editor); WSSCC (Editor) (2000): Summary Report of Bellagio Expert Consultation on Environmental Sanitation in the 21st Century. Duebendorf & Geneva: Swiss Federal Institute for Aquatic Science and Technology EAWAG & Water Supply and Sanitation Collaborative Council. URL [Accessed: 04.08.2010]. PDF
ESREY, S. A. (2000): Towards a Recycling Society. Ecological Sanitation – Closing the Loop to Food Security. In: Proceedings of the 1st Int. Symposium on Ecological Sanitation in Bonn 30th – 31st October 2000. PDF
GALLATI, M. (2007): Ozonierung modernisiert die Abwasserreinigung. In: Schweizer Gemeinde 44, 19-20. PDF
OTIS, R. (1996): Small diameter gravity sewers: experience in the United States. In: Low-Cost Sewerage , 123-133.
SUSANA (Editor) (2008): Towards more Sustainable Sanitation Solutions. Eschborn: Sustainable Sanitation Alliance SuSanA. URL [Accessed: 21.04.2012]. PDF
UNDP – UNITED NATION’S DEVELOPMENT PROGRAMME (Editor) (2006): Human Development Report 2006. Beyond scarcity: Power, poverty and the global water crisis. New York, Palgrave Macmillan: United Nations Development Programme (UNDP). URL [Accessed: 17.04.2012]. PDF
WINDBLAD, U.; SIMPSON-HERBERT, M. (2004): Ecological Sanitation - revised and enlarged edition. (pdf presentation). Sweden: Stockholm Environment Institute. URL [Accessed: 04.08.2010]. PDF

ALSEN, K.W. (Editor); JENSSEN, P. (Editor) (2004): Ecological Sanitation: for Mankind and Nature. Aas: Norwegian University of Life Sciences. URL [Accessed: 21.04.2012]. PDF
A short booklet explaining the notion of ecological sanitation, closing the water and the nutrient/energy loops and also giving practice examples.
EAWAG (Editor); SANDEC (Editor); WSSCC (Editor) (2000): Summary Report of Bellagio Expert Consultation on Environmental Sanitation in the 21st Century. Duebendorf & Geneva: Swiss Federal Institute for Aquatic Science and Technology EAWAG & Water Supply and Sanitation Collaborative Council. URL [Accessed: 04.08.2010]. PDF
This report summarises the Bellagio principles, which can be considered a basis for sustainable sanitation approaches.
ESREY, S. ; ANDERSSON, I. (2001): Ecological Sanitation. Closing the loop. In: Urban Agriculture UA Magazine 3 - Health aspects of urban agriculture. URL [Accessed: 04.08.2010]. PDF
A short and very well written 2-page document explaining the concept of ecological sanitation and its benefits to urban agriculture.
JENSSEN, P.D.; HEEB, J.; HUBA-MANG, E.; GNANAKAN, K.; WARNER, W.; REFSGAARD, K.; STENSTROEM, T.A.; GUTERSTRAM, B.; ALSEN, K.W. (2004): Ecological Sanitation and Reuse of Wastewater. Ecosan. A Thinkpiece on ecological sanitation. Norway: The Agricultural University of Norway. URL [Accessed: 19.04.2010]. PDF
This paper shows that there are comprehensive experiences and available technologies that meet new and sustainable sanitation requirements. Ecological sanitation constitutes a diversity of options for both rich and poor countries, from household level up to wastewater systems for mega-cities and needs to become recognised by decision-makers at all levels.
SUSANA (Editor) (2008): Towards more Sustainable Sanitation Solutions. Eschborn: Sustainable Sanitation Alliance SuSanA. URL [Accessed: 21.04.2012]. PDF
The vision document of the sustainable sanitation alliance explains the notion of sustainable sanitation in detail.
WINDBLAD, U.; SIMPSON-HERBERT, M. (2004): Ecological Sanitation - revised and enlarged edition. (pdf presentation). Sweden: Stockholm Environment Institute. URL [Accessed: 04.08.2010]. PDF
This book is one of the most fundamental and important books that defined the concept of ecological sanitation. The first version came out in 1998 - this version presents the findings of over ten years of research and development in ecological sanitation supported by SIDA (Swedish International Development Cooperation Agency).
LUETHI, C.; PANESAR, A.; SCHUETZE, T.; NORSTROEM, A.; MCCONVILLE, J.; PARKINSON, J.; SAYWELL, D.; INGE, R. (2011): Sustainable Sanitation in cities: a framework for action. Sustainable Sanitation Alliance (SuSanA) & International Forum on Urbanism (IFoU), Papiroz Publishing House, The Netherlands. URL [Accessed: 15.02.2011]. PDF
This book repared by partners of the Sustainable Sanitation Alliance (SuSanA) network is a real eye-opener. It takes a look at some of the methods that have worked well in the past, to guide us in solving the problems of the future. By addressing sanitation as a key element of the urban metabolism, and by linking sanitation with urban planning and neighbouring sectors like solid waste management or waste recycling, it allows for a holistic approach. In the cities of tomorrow, we will need to focus more on recycling energy. A good example being biogas generation from wastewater and sludges. Water will also become an increasingly scarce commodity. Greywater (from showers and sinks) can be treated in urban constructed wetlands or used to water and fertilise urban green spaces. Such examples of productive sanitation systems will form an integral part of infrastructure in sustainable cities.
KIEFHABER, P. (2010): Sustainable Water and Waste-Water Management: Energy- and Material-Flow-Management - Quo vadis?. The Example 'Phosphorus-Recycling'. Kaiserslauten: Dr. Kiefhaber + zebe ingenieur consult gmbh. PDF
By taking the example of phosphorus, this essays shows that besides encompassing elaborate treatments to produce high quality water discharges to recipient bodies, the various substances brought into the water by human activities might also be extraordinarily valuable.
WINSA (2011): What Happens When the Pit is Full?. Developments in On-Site Faecal Sludge Management (FSM). Durban: Water Information Network South Afrika (WINSA). URL [Accessed: 06.10.2011]. PDF
This seminar report helps people responsible for the sustainable operation of on-site sanitation systems. It shows new developments in the field and contains a lot of detailed information about Faecal Sludge Management (FSM).
UN WATER (Editor) (n.y.): Sanitation Sustains Clean Environments. United Nations Water (UN WATER). URL [Accessed: 17.10.2011]. PDF
This factsheet shortly describes how sanitation can add to sustainability in an environmental way.
WATER AID (Editor) (2011): Construction of Ecological Sanitation Latrine. Kathmandu: Water Aid. URL [Accessed: 19.10.2011]. PDF
This document sets out the principles for adopting an ecological sanitation approach, as well as providing guidance on the construction ecological sanitation latrines and their operation. It is intended to support sanitation field practitioners and WaterAid in Nepal ’s partners in the delivery of appropriate services and technologies to fit the needs of different users. .It is also equally hoped that this document will be of value to other organisations and sector stakeholders involved in sanitation promotion and ecological sanitation.
MUENCH, E. von (Editor); INGLE, R. (Editor); MBALO, D (Editor); KAPPAUF, L. (Editor) (2012): Compilation of 13 Factsheets on Key Sustainable Sanitation Topics. Eschborn: Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH. URL [Accessed: 07.05.2012]. PDF
This factsheet book is a compilation of 13 thematic factsheets which were produced by the eleven SuSanA working groups (WGs): WG1 - Capacity development; WG 2 - Finance and economics; WG 3 - Renewable energies and climate change; WG 4 - Sanitation systems, technology options, hygiene and health; WG 5 - Food security and productive sanitation systems; WG 6 - Cities and planning; WG 7 - Community, rural and schools (with gender and social aspects); WG 8 - Emergency and reconstruction situations; WG 9 - Sanitation as a business and public awareness; WG 10 - Operation and maintenance; WG 11 - Groundwater Protection. What makes these factsheets special is that they are multi-authored by people from different organisations and by free-lance consultants. The factsheets were developed in a long process involving many discussions and review loops which were mostly carried out in public, e.g. at working group meetings, with the working group mailing lists or, since July 2011, also in the open SuSanA discussion forum.
NATURE (Editor); MORGAN, P.; OTTERPOHL, R.; PARAMASIVAN, S.; HARRINGTON, E. (2012): Ecodesign: The Bottom Line. In: Nature: International Weekly Journal of Science 486, 186-189. URL [Accessed: 19.06.2012]. PDF
There is no single design solution to sanitation. But there are universal principles for systematically and safely detoxifying human excreta, without contaminating, wasting or even using water. Ecological sanitation design — which is focused on sustainability through reuse and recycling — offers workable solutions that are gaining footholds around the world, as Nature explores on the following pages through the work of Peter Morgan in Zimbabwe, Ralf Otterpohl and his team in Germany, Shunmuga Paramasivan in India, and Ed Harrington and his colleagues in California.
NATURE (Editor); NARAIN, S. (2012): Sanitation for All. In: Nature: International Weekly Journal of Science 486, 185. URL [Accessed: 19.06.2012]. PDF
Water pollution from sewage is causing great damage to India. The nation needs to complete its waste systems and reinvent toilet technologies.
Graham, J.; Polizotto, M.L. (2013): Pit Latrines and Their Impacts on Groundwater Quality: a systematic Review. Advance Publication. In: Environmental Health Perspectives. URL [Accessed: 09.04.2013]. PDF
This study reviews empirical studies on the impact of pit latrines on groundwater quality and identifies knowledge gaps regarding the potential and consequences of groundwater contamination by latrines.

SHRESTHA, R.R. (2010): Eco Home for Sustainable Water Management- A Case Study in Kathmandu. Kathmandu: United Nation Development Program (UNDP). URL [Accessed: 05.01.2011]. PDF
This paper describes a case study of a house in Kathmandu where rainwater is used for all purposes including drinking, greywater is recycled for non drinkable purposes and human excreta is utilized as a fertilizer by adopting ecological sanitation technique.
INGLE, R.; MUENCH, E. von (2011): Compilation of 27 Case Studies on Sustainable Sanitation Projects from Sub-Sahara Africa. Eschborn: Sustainable Sanitation Alliance (SuSanA). URL [Accessed: 29.05.2012]. PDF
The Sustainable Sanitation Alliance (SuSanA) publishes case studies of sustainable sanitation projects from around the world to demonstrate the wide range of available technologies for sustainable sanitation systems. This case study book only comprises those project examples which are from sub-Saharan African countries. These case studies are useful for decision makers, planners, researchers, engineers and the interested public. They have compiled descriptions of well-running projects as well as of less successful projects so that we can learn from past mistakes.
ECOSAN CLUB (Editor) (2010): Use of Urine. Vienna: Ecosan Club. URL [Accessed: 05.08.2010]. PDF
A "Sustainable Sanitation Practice" journal by Ecosan Club, focussing on the use of urine and presenting some case studies.
SATISH, S.; THAKUR, P.; PATANGE, P.; ESF (Editor) (n.y.): Sustainable Sanitation Practises Integrating Water and Health. Pune: Ecosan Services Foundation (ESF). URL [Accessed: 22.06.2011]. PDF
This document is about Ecosan, as a solution to sanitation problems concerning health and contaminated water.
THAKUR, P.; PANSE, D.; ESF (Editor) (n.y.): Success Stories of Sustainable Sanitation Initiatives in India by ESF. Pune: Ecosan Services Foundation (ESF). URL [Accessed: 22.06.2011]. PDF
ESF is working in the diversified sectors in rural, peri-urban and urban areas focusing on the agricultural sector, schools, communities, the Eco-village project, sanitation plans for pilgrimage towns and upcoming projects in local government bodies with a participatory approach and cost effective sustainable sanitation solutions. This document shows some examples.
PANSE, D.; HEEB, J.; SATISH, S.; ESF (Editor) (2007): Large Scale Ecosan Capacity Building Project in India. Pune: Ecosan Services Foundation (ESF). URL [Accessed: 22.06.2011]. PDF
In this paper, a large scale Ecosan capacity building project for introducing the Ecosan approach to several target groups in India is described.
MUELLEGGER, E. (Editor); LANGERGRABER, G. (Editor) (2012): Water Reuse. Vienna: EcoSan Club. URL [Accessed: 18.07.2012]. PDF
To meet the challenges extremely efficient water use is necessary to achieve overall improvements in water productivity. Multi-use systems will therefore be crucial in integrated water management. Different examples show how water can be reused and recycled and thus increasing water efficiency in urban, peri-urban and rural areas. Issue 11 of Sustainable Sanitation Practice (SSP) on „Water reuse“ shows 3 examples for the use of treated wastewater for irrigation in agriculture: (1.) The first paper presents results from a long-term study (agricultural wastewater reuse) carried out in Sicily, Italy. (2.) The second paper presents activities on water management in the Oasis of Figuig, Morocco. (3.) The third paper presents practical experiences from a feasibility study on technology selection for wastewater treatment and effluent reuse schemes in Anza village, Palestine.

CORCORAN, E. (Editor); NELLEMANN, C. (Editor); BAKER, E. (Editor); BOS, R. (Editor); OSBORN, D. (Editor); SAVELLI, H. (Editor) (2010): Sick Water? The central role of wastewater management in sustainable development. A Rapid Response Assessment. United Nations Environment Programme (UNEP), UN-HABITAT, GRID-Arendal. URL [Accessed: 05.05.2010]. PDF
This book not only identifies the threats to human and ecological health that water pollution has and highlights the consequences of inaction, but also presents opportunities, where appropriate policy and management responses over the short and longer term can trigger employment, support livelihoods, boost public and ecosystem health and contribute to more intelligent water management.
NARAIN, S. (2002): The Flush Toilet is Ecologically Mindless. In: Down to Earth 19. URL [Accessed: 21.04.2012]. PDF
Critical article by environmental activist and Stockholm Water Price Laureate Sunita Narain, on why it is mindless to waste so much clean water to flush away excreta.
SEI (Editor) (2008): Sanitation Now Money down the drain. Stockholm: Stockholm Environment Institute. URL [Accessed: 21.04.2012]. PDF
This special issue of "Sanitation Now", a magazine on the global sanitation crisis published by the Stockholm Environment Institute, focuses on the millions of dollars that are lost through the lack of sanitation - such as costs caused through polluted water, diarrhoea related diseases and deaths, and losses in tourist income. Its baseline is that poor sanitation equals more poverty and a stunted economic growth.
TUHUS-DUBROW (2008): Waste? Not. In: The Boston Globe. URL [Accessed: 21.02.2010]. PDF
Critical article on conventional end-of-pipe wastewater approaches, introducing some alternatives such as biogas digester, arborloos or the fossa alterna.
ONLINENURSINGPROGRAMS (Editor) (2012): Poop - The Four-Letter Word no One's Talking About. Online Nursing Programs. URL [Accessed: 07.05.2012]. PDF
After you go to the bathroom, chances are you flush your waste. But globally, not all waste gets flushed. Check out this great graph about this topic. You can also download the GIF-File.
UN Water; UN Water (Editor) (2013): Water Quality Factsheet. UN Water. URL [Accessed: 09.04.2013]. PDF
Thematic factsheet. Every day, 2 million tons of human wastes are disposed of in watercourses, and in developing countries 70 % of industrial wastes are dumped untreated into waters where they pollute the usable water supply. But not only industry contaminates our water resources, so do also agriculture. The contribution of the food sector to the production of organic water pollutants, are in high-income countries 40 % and in low-income countries 54 %.

KROPAC (2009): Ecological Sanitation - Closing the loop. Basel: seecon. PDF
An excellent PowerPoint presentation on the concept of ecological sanitation.
UDERT, K.; TILLEY, E. (n.y.): Sanitation Systems and Technologies for Developing Countries. Pdf Presentation. Duebendorf: Swiss Federal Institute of Aquatic Science (Eawag). PDF
This presentation gives an overview about existing sustainable sanitation techniques.
ROSEMARIN, A. (2012): Sanitation Systems and their Functionality in Health Protection. Stockholm: Stockholm Environment Institute (SEI). URL [Accessed: 30.05.2012]. PDF
This presentation gives you an overview about sustainable sanitation and its benefits.
The official website of the Sustainable Sanitation Alliance SuSanA. SuSanA is a loose network of a number of organizations active in the field of sanitation, founded in 2007. The goals and objectives of SuSanA are to contribute to the achievement of the MDGs, to raise awareness on what sustainable sanitation solutions are and to promote them on a larger scale. The website contains a number of factsheets by the different SuSanA working groups on various subjects related to sustainable sanitation. There is section where everyone can upload important documents.
http://www.waterlandpeople.net/ [Accessed: 27.04.2010]
The initiative “Water, Land and People: Voices and insights from three continents“ promoted by the Swiss Agency for Development and Cooperation (SDC) aims at sharing and deepening the knowledge base of SDC and partners in order to improve the development strategies and policies with regard to Integrated Water Resource Management (IWRM) with emphasis on the aspect Water for Food.
http://www.ecosanres.org [Accessed: 06.05.2010]
Official web page of the Ecological Sanitation Research Programme (EcoSanRes). The EcosanRes Programme aims to develop and promote sustainable sanitation in the developing world through capacity development and knowledge management as a contribution to equity, health, poverty alleviation, and improved environmental quality. It contains numerous helpful publications, and also allows you to gain access to the ecosanres discussion forum, currently the most active discussion forum on ecological sanitation.
http://www.gtz.de/ecosan [Accessed: 06.05.2010]
The official web page of the GTZ ecosan programme, containing a wealth of information on ecological sanitation, an extensive library, links to an ecosan photo collection and a number of useful publications.
http://www.ecosan.at [Accessed: 05.08.2010]
The Ecosan Club was funded as a non-profit association in 2002. It aims at closing material cycles in settlements, at promoting ecological approaches to sanitation, and offers consultancy, information services, and support in regards to specific information on ecological and sustainable sanitation. It publishes the magazine “SSP”, sustainable sanitation in practice, four times a year.
www.unwaterlibrary.org [Accessed: 15.01.2013]
This virtual library provides access to recent water and sanitation related publications produced by the United Nations system. It is available in English (www.unwaterlibrary.org) and in Spanish (www.bibliotecaonuagua.org) but publications are accessible in different languages when available (including the 6 official UN languages: Arabic, Chinese, English, French, Russian and Spanish).