1. DEMO-VERSION: LINKS TO EXTERNAL DOCUMENTS DO NOT WORK!
M2: ecosan - an Approach to Human Dignity, Community Health and Food Security
M 2-1: ecosan concept
(1)
J. Heeb
K. Conradin
Dr. Johannes Heeb, International Ecological Engineering Society & seecon international
Prof. Dr. Petter Jenssen, Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences
Dr. Ken Gnanakan, ACTS Bangalore, India
Katharina Conradin, seecon international
© 2006
seecon
International gmbh
ACTS
Agriculture -Crafts - Trades - Studies

2. Credits
K. Conradin
Materials included in this CD-ROM comprise materials from various organisations. The materials complied on this CD are freely available at the internet, following the open-source concept for capacity building and non-profit use, provided proper acknowledgement of the source is made. The publication of these materials on this CD-ROM does not alter any existing copyrights. Material published on this CD for the first time follows the same open-source concept for capacity building and non-profit use, with all rights remaining with the original authors / producing organisations.
Therefore the user should please always give credit in citations to the original author, source and copyright holder.
We thank all individuals and institutions that have provided information for this CD, especially the German Agency for Technical Cooperation GTZ, Ecosanres, Ecosan Norway, the International Water and Sanitation Centre IRC, the Stockholm Environment Institute SEI, the World Health Organisation WHO, the Hesperian Foundation, the Swedish International Development Cooperation Agency SIDA, the Department of Water and Sanitation in Developing Countries SANDEC of the Swiss Federal Institute of Aquatic Science and Technology, Sanitation by Communities SANIMAS, the Stockholm International Water Institute SIWI, the Water Supply & Sanitation Collaborative Council WSSCC, the World Water Assessment Programme of the UNESCO, the Tear Fund, Wateraid, and all others that have contributed in some way to this curriculum.
We apologize in advance if references are missing or incorrect, and welcome feedback if errors are detected.
We encourage all feedback on the composition and content of this curriculum. Please direct it either to or
seecon
K. Conradin

3. Credits ecosan Curriculum - Credits
K. Conradin
ecosan Curriculum - Credits
Concept and ecosan expertise: Johannes Heeb, Petter D. Jenssen, Ken Gnanakan
Compiling of Information: Katharina Conradin
Layout: Katharina Conradin
Photo Credits: Mostly Johannes Heeb & Katharina Conradin, otherwise as per credit.
Text Credits: As per source indication.
Financial support: Swiss Development Cooperation (SDC)
How to obtain the curriculum material
Free download of PDF tutorials:
Order full curriculum CD:
€ 50 (€ 10 Developing Countries)
Release: 1.0, March 2006, 1000 copies
Feedback: Feedback regarding improvements, errors, experience of use etc. is welcome. Please notify the above
-addresses.
Sources Copyright: Copyright of the individual sources lies with the authors or producing organizations. Copying is allowed as long as references are properly acknowledged.
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4. Conventional waterborne sanitation Water use Development Limitations
Contents
Source: (1)
Content Overview
Conventional waterborne sanitation
Water use
Development
Limitations
Cost & Water Consumption
Design
Nutrient Recovery
High Energy Input
Summary of limitations
Ecological sanitation as a sustainable alternative
The Bellagio Principles
Advantages of ecosan systems
technical characteristics
turning waste into resources
ecosan - Different Basic Types of Projects
Advantages of ecosan Systems:
Closing the Loop(s)
Multidisciplinarity
Conclusion

5. Johannesburg summit on sustainable development:
Content Overview
Source: (1)
Johannesburg summit on sustainable development:
goal of providing sanitation and clean water to at least half of those presently lacking it by the year 2015.
Unlikely with conventional systems (high cost, high energy demand, management requiremnets
Sustainability of conventional wastewater systems often questionable, especially with improper management.
Resource recycling sanitation systems  ecological sanitation systems,
based on source separation:
greywater (kitchen, sinks, showers)
brownwater (faecal matter & water)
yellowwater (urine).
The Johannesburg summit on sustainable development set the goal of providing sanitation and clean water to at least half of those presently lacking it by the year However, if based on conventional water flushed sanitation systems, it is unlikely that this millennium goal can be achieved.
On the one hand, conventional systems involve large financial costs for construction and operation, consume energy and chemicals, have great management requirements, and a high demand for water. Mostly, they also require educated and trained operators. Yet, effective wastewater treatment facilities are required to prevent negative impacts on public health and the environment.
The sustainability of conventional wastewater systems, commonly used in the developed world is many times questionable. Most plants require large inputs of energy whilst at the same time, clean water and nutrients are wasted. As populations grow and developing countries increase their standard of living, the environmental strain will increase further. The development of alternative, more sustainable wastewater technologies is therefore of paramount importance.
In the last decade or so, new sustainable, resource recycling sanitation systems, the so called ecological sanitation systems, have become available. Ecological sanitation can be based on source separation in which domestic waste is separated at source: greywater (water from sinks, showers, and laundry machines) and brownwater (faecal matter & water), and yellowwater (urine). Brownwater and yellowwater can also be combined, forming blackwater. This source separation facilitates recycling and provides more sustainable solutions for domestic waste and wastewater than conventional systems. Systems based on source separation transform waste into valuable resources, such as fertilisers and soil amendments (12).
Source: (12)
Greywater is only slightly polluted wastewaters from dishwashing, showers, laundry machines, water from sinks etc. Greywater makes up for the largest share of wastewater.
Yellow water is either urine diluted with flushwater or pure urine. Urine contains most of the nutrients we excrete again, but only has a very low, if at all, pathogen count. However, we also excrete micro-pollutants or endocrine substances through urine.
Brownwater refers to faeces mixed with (flushing) water, but no urine. Most of the pathogens and a high proportion but rather little of the nutrients are contained here.
Blackwater is urine and faeces mixed with or without domestic wastewater from showers, washing machines, sinks etc.

6. Definitions of sanitation/ecological sanitation
What does sanitation actually include?
safe collection, storage, treatment and disposal/re-use/ recycling of human excreta (faeces and urine)
management/ re-use/ recycling of solid wastes (trash or rubbish)
drainage and disposal/ re-use/ recycling of household wastewater (often refereed to as sullage or grey water)
drainage of stormwater
treatment and disposal/ re-use/ recycling of sewage effluents
collection and management of industrial waste products
management of hazardous wastes, including hospital wastes, and chemical/radioactive and other dangerous substances.
What does sanitation actually include?
Most professionals would agree that “sanitation” as a whole is a “big idea” which covers inter alia:
safe collection, storage, treatment and disposal/re-use/ recycling of human excreta (faeces and urine)
management/ re-use/ recycling of solid wastes (trash or rubbish)
drainage and disposal/ re-use/ recycling of household wastewater (often refereed to as sullage or grey water)
drainage of stormwater
treatment and disposal/ re-use/ recycling of sewage effluents
collection and management of industrial waste products
management of hazardous wastes, including hospital wastes, and chemical/radioactive and other dangerous substances.
Source: (3)
Source: (3)

7. Conventional waterborne sanitation
“The idea that human excreta are wastes with no useful purpose is a modern misconception. It has led to the development of so-called “drop and store” or “flush and forget” sanitation solutions, where precious drinking water is used to transport excreta into the water cycle misusing our rivers, oceans and aquifers as a sink for untreated waste.” (19)
“The idea that human excreta are wastes with no useful purpose is a modern misconception. It has led to the development of so-called “drop and store” or “flush and forget” sanitation solutions, where precious drinking water is used to transport excreta into the water cycle misusing our rivers, oceans and aquifers as a sink for untreated waste.” (19)
Waterborne sanitation systems mix faeces, urine, flush water and toilet paper with grey water, storm water and industrial effluents, usually overtaxing the design capacity of the treatment plants, if such a facility exists, as very few communities in the world are able to afford fully functional sewage systems. Simply put, flush sanitation has a dismal track record because all sewage systems contaminate the environment (14).
Source: (4)

8. Conventional Waterborne Sanitation
J. Heeb
Despite inherent flaws: improvement of hygienic situation in many places
 dangerous substances moved out of cities
Nevertheless, external costs not considered:
Environmental contamination
eutrophication of waterbodies,
loss of fertilizer worth billions of dollars every year
Advantages and limitations for both conventional and ecological sanitation have to be considered carefully!
As stated above, waterborne sanitation has some inherent flaws that make it unsuitable in many parts of the world. A high water consumption, the need for expensive pipe networks and treatment facilities as well the discharge of untreated wastewater into waterbodies in many parts of the world are just some examples.
However, it cannot be denied that – at least in most developed countries – waterborne sanitation was also able to significantly improve the hygienic standards in many places. Health status has increased, and with functioning wastewater treatment plants, most pollutants are removed before the treated wastewater is again discharged into rivers. Looked at conventional sanitation from this angle, it has been able to improve the sanitary conditions in many parts of the world, and has thus saved a great number of lives. Nevertheless, external costs of conventional sanitation are often not considered carefully enough: Environmental contamination through substances that remain active even in treated wastewater, the subsequent eutrophication of waterbodies, and the loss of fertilizer worth billions of dollars every year are facts that cannot be neglected.
It is though necessary to consider each advantages and disadvantages of conventional and ecological sanitation. In some places, in particular where some infrastructure already exists, conventional wastewater treatment systems can be an option that will improve living standards and protect the environment. For a more complete overview of conventional sanitation systems, please refer to the Annex Module, which lists dozens of systems individually with their advantages and limitations respectively.
“Eutrophication refers to the gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aquatic ecosystem such as a lake, a pond, or also rivers (though the risk is higher if is a standing waterbody). The productivity or fertility of such an ecosystem increases as the amount of organic material that can be broken down into nutrients increases. This material enters the ecosystem primarily by runoff from land that carries debris and products of the reproduction and death of terrestrial organisms. Moreover, cultural eutrophication occurs when man speeds up the aging process by allowing excessive amounts of nutrients in such forms as sewage, detergents, and fertilizers to enter the ecosystem. Blooms, or great concentrations of algae and microscopic organisms, often develop on the surface, preventing the light penetration and oxygen absorption necessary for underwater life. In the end, the algae might consume so much oxygen and sunlight that all other aquatic life deceases.” (8)

9. Conventional waterborne sanitation: Water use
With conventional waterborne flush-toilets, we mix
roughly 50 kg of faecal matter (per person/year)
50 kg
500 L
roughly 500 l of urine (per person/year)
with roughly 20’000l of clean flushwater* (11), based on a volume of 8l per flush
20’000 L
We thus produce more than 20’000 L of highly polluted, pathogenic wastewater.
This is a figure based on the Swiss average, for a toilet that uses about 8 L of Water per flush. However, toilets (mainly in North America) can use up to 5 Gallons (roughly 23l) just for one flush! This would add up to a water use (just for flushing!!) of almost 50’000 l per person and year – and the fact that the polluting substances make up just 1 % of the total wastewater!
If this wastewater is discharged untreated into rivers, an even higher amount of water is polluted.
* Based on the Swiss average for a toilet that uses about 8 L of Water per flush.

10. Conventional sanitation systems: Development
K. Conradin
Relatively new technology (end of the 19th century).
Reason: increased water consumption through piped water supply  increased wastewater production.
Wastewater in city streets: illnesses, cholera (Germany 1982)
Sewer systems to improve hygienic situation:
 health and hygienic standards better in cities
 excreta “safely” carried elsewhere.
 Problem is shifted downstream!
Only when serious water pollution was recognized: wastewater treatment plants (1960)
Current conventional forms of wastewater management and sanitation fall either under the category of waterborne or dry systems. In both cases the design is based on the premise that excreta is waste, and that waste should be disposed of. It also assumes that the environment can safely assimilate this waste.
“Modern” waterborne sewer systems are a relatively new technology, which only began to spread in European cities from around the end of the 19th century. The reason for this was that piped water supplies lead to an increased water consumption, and wastewater production. This led to streams and stagnant pools of wastewater in city streets, causing outbreaks of cholera and other diseases. Only in 1892, there was an outbreak of cholera in Hamburg, a major city in the north of Germany. Within only six weeks, more than 10’000 of its inhabitants died. Richard Evans, who wrote a novel on this outbreak of cholera, describes the causes as follows: This [outbreak] was due to the fact that tradition and modernity were so balefully intertwined that political, social and ecological problems lead to a catastrophe (5).
To improve the hygienic standards, sewer systems were gradually introduced. Those systems were able to greatly improve health and hygienic standards in the cities themselves, since faecal matter was now safely carried elsewhere. However, with a solution like this, the problem is not solved, but the pollution is just moved elsewhere. Only later, when the drainage of sewage into waterbodies was seen to cause serious water pollution, mechanical wastewater treatment plants, biological treatment for the degradation of organic substances, and tertiary treatment for the removal of nutrients were added to reduce the pollution and the eutrophication of the receiving water bodies. These now represent the present state-of-the-art in wastewater treatment (1).
Sources: (5), (1)

11. Conventional sanitation systems: Development
K. Conradin
Improvement of the hygienic situation in a large number of urban areas.
Relatively easy disposal of where water supply is abundant,
hydraulic transport of wastewater away from urban areas.
pollution of surface waters within urban areas avoided,
However, due mainly to a lack of resources: incorrectly operated in many countries.
Thus:
improvements in the sanitary situation in sewered areas of towns rich areas)
deterioration in the sanitary situation in surrounding, unsewered, and usually poorer, neighbourhoods,
Exposing of poorer communities to contaminated water in their every-day life,
Such wastewater treatment plants have improved the hygienic situation in a large number of urban areas. Particularly in those where water supply is abundant, treated wastewater can be relatively harmlessly disposed of, and the costs of operation and maintenance can be assured. When built and functioning correctly, conventional waterborne sewers and treatment plants allow a relatively well assured hydraulic transport of excreta, used water and rainwater away from urban areas. They also help avoid the pollution of surface waters within urban areas, which are often a source of health and environmental problems. This obviously improves the hygienic situation of those inhabitants of urban areas being served by well functioning sewer systems.
However, due mainly to a lack of resources, these systems cannot be correctly operated in many countries. As a result, improvements in the sanitary situation in sewered areas of towns (which most often cover the wealthier section of the population) often directly lead to a deterioration in the sanitary situation in surrounding, unsewered, and usually poorer, neighbourhoods, as sewage is often discharged with little or no treatment into water bodies. Poorer communities are often exposed to contaminated water in their every-day life, using it as a source of drinking or washing water or when water levels rise during flooding. These problems become particularly serious when there is a rapid increase in the urban population.
Source: Adapted from (1, 3)
Source: Adapted from ( 3, 6)

12. over 50% of onsite/cluster systems are in cities and their suburbs
Limitations: Cost
High maintenance and operation costs
Wastewater
treatment plant
Sewer lines
Graphics: P. Jenssen
Collection system %
Treatment %
In the US:
37% of all new developments are serviced by onsite or decentralised systems
over 50% of onsite/cluster systems are in cities and their suburbs
Conventional centralised systems require a huge financial investment, and have very high maintenance and operation costs. The difficulties caused by these expenses do not only prevent developing nations from correctly building and operating centralised sanitation systems, but industrialised nations also face huge problems in the maintenance and operation of their sewer systems and treatment plants.
In Latin America, less than 20% of the wastewater collected is actually treated, whilst in Europe, of 540 major cities, only 79 have advanced tertiary sewage treatment, 223 have secondary treatment, 72 have incomplete primary treatment and 168 cities have no or an unknown form of treatment of their wastewater (6). Worldwide, only a very low percentage of wastewater undergoes some form of treatment at all.

13. Limitations: Not implemented / non-functioning Plants
Latin America:
less than 20% of the wastewater collected is actually treated,
Europe: of 540 major cities,
only 79 have advanced tertiary sewage treatment, 223 have secondary treatment,
72 have incomplete primary treatment and
168 cities have no or an unknown form of treatment of their wastewater (6).
Worldwide, only a very low percentage of wastewater undergoes some form of treatment at all.

14. Limitations: Design
J. Heeb
Discharge from functioning conventional wastewater treatment plants is often still not safe from a health point of view. Often insufficient removal of
pathogenic organisms
nutrients
Problem: micropollutants (pharmaceutical residues)  negative effects on aquatic life.
Heavy rainfall: overflow of treatment facilities possible  untreated effluent into rivers (1).
Central sewage treatment plants are much more susceptible to total failure than de-centralised systems.
Albeit such systems contribute to a healthier environment in some parts of the cities where they are installed, they do the opposite for those living downstream, or for those living in the poorer areas which are not connected to a central sewage plant.
Even when functioning properly, the discharge from conventional wastewater treatment plants is still not safe from a health point of view. Often, the effluents even fail to meet the quality requirements of bathing water. Conventional treatment plants have been developed for the removal of large particles, biodegradable organic substances and nutrients in order to protect receiving waters. The reduction of pathogenic organisms as well as the extraction of nutrients is, however, less satisfying.
Moreover, effluents in industrialised countries often contain small amounts of pharmaceuticals or other micropollutants. The effects of pharmaceutical residues in the effluent and their impact on the environment and humans living downstream who obtain their drinking water from the same river are also being discussed.
For combined sewer systems (carrying both storm water and wastewater), a further problem is that heavy rainfall generally leads to the diluted wastewater being discharged untreated directly into rivers as treatment plants are only designed for a limited influent (1).
Additionally, central sewage treatment plants are much more susceptible to total failure than de-centralised systems. As an example: in Switzerland, 95% of all households are connected to the public sewer systems, which lead to centralised treatment plants (10). However, due to heavy rainfalls and mudslides, one of these treatment plant was destroyed. To date, the untreated wastewater of several thousand inhabitants as well as some farms and small industries has been discharged for more than 2 months untreated into a river.
“Micropollutants refers to pollutants which usually appear in very small amounts in the environment. In the case of wastewater, one mostly refers to substances such as pharmaceuticals and synthetic or natural hormones (the latter are also called endocrine substances). These substances have a negative effect, especially if they are released in water bodies, as they can influence the sexual development of animals living in the water.
Moreover, some pharmaceuticals can also accumulate in the body fat tissue, and can thus eventually pose a threat to human beings again, as they are feeding at the top of the food web.” (7)

15. Limitations: On-Site Sanitation Systems
On-site wastewater disposal systems: groundwater contamination possible (infiltration of wastewater)
However, shortcomings also conventional on-site wastewater disposal systems have their shortcomings. Very often, they lead to groundwater contamination, which gets worse with increasing population densities. In many densely populated areas this has led to nitrate concentrations in groundwater, which exceed the maximum level recommended by the WHO for drinking water and which have been linked to serious health problems, particularly for babies.
Shallow groundwater is still a major source of water supply in rural and peri-urban areas, especially for the poor. The design of the conventional “drop and store” pit-latrine (and of most other on-plot systems) is not compatible with this practice as it deliberately aims to retain only solid matter in the pit and infiltrate as much of the liquids as possible into the subsoil. As these liquids contain all the soluble elements of the excreta as well as viruses and pathogens, this type of sanitation, depending on the hydro-geological situation, can be a highway to groundwater contamination. There may also be topographical constraints against the construction of pit latrines, for example where the ground is rocky or on sites that are subject to flooding (1).
Pit toilets may be a solution only when the infiltration cannot possible endanger water sources. This depends on the infiltration capacity, the distance to the drinking water source, the kind of the drinking water source etc. To be really on the safe side, pit latrines should therefore only be constructed in close collaboration with experts – which is often very difficult.
Source: (4)

16. Limitations: Nutrient Recovery
P. Jenssen
R. Otterpohl
Heavy metals and organic
micropollutants
Nutrient recovery often impossible:
high concentrations of heavy metals & hazardous substances (due to the mixing of domestic wastewater with industrial wastewater
Huge demand for energy intensive artificial fertilisers, in response to the problem of decreasing soil fertility. (16)
While the above are serious disadvantages of conventional wastewater disposal systems, one of the fundamental problems is that they do not facilitate the reuse of macro and micro nutrients present in the wastewater. This lack of nutrient recovery and use leads to a linear flow of nutrients from agriculture, via humans to recipient water body bodies. The valuable nutrients and trace elements contained in human excrement are very rarely re-channelled back into agriculture in conventional systems. Even when sewage sludge is used in agriculture, only a very small fraction of the nutrients contained in the excrement are reintroduced into the living soil layer. Most are either destroyed in the treatment process (e.g. by nitrogen elimination) or enter the water cycle, where they pollute the environment, causing the eutrophication of lakes and rivers.
Source: Adapted from (1), (6), (9)
The use of sewage sludge from central wastewater systems is also frequently restricted as it contains high concentrations of heavy metals and other hazardous substances, due to the mixing of domestic wastewater with industrial wastewater and storm-water run-off from streets. Not returning the nutrients to the soil has led to a situation where there is a huge demand for chemical fertilisers, in response to the problem of decreasing soil fertility. To produce the required chemical fertilisers large amounts of energy are needed, and finite mineral resources, such as phosphorous, must be exploited (16).

17. Limitations: High Energy Input
Conventional wastewater treatment with nitrogen removal Adapted from: (16)
Conventional wastewater treatment with nitrogen removal
Source: P.D. Jenssen
Nitrogen removal is required in most european countries in order to reduce the input to waterbodies or the sea (eutrophication). This process is being done in large treatment plants. The most common way to remove nitrogen is by biological nitrification and subsequent denitrification. This process transforms most of the nitorgen to N2 – however, some is also discharged as N2O (nitrous oxide). N2O is a potent greenhouse gas. It has been impossible to eliminate the N2O emission because we do not completely control the biological processes and especially not the nitrogen cycle. Nitrogen removal ususally doubles the energy needed to operate the treatment system (16).

18. Limitations: High Energy Input
Conventional wastewater treatment with nitrogen removal Adapted from: (16)
Graphics: P.D. Jenssen
If electricity is produced from coal or oil, SO2 (sulphur dioxide) and NOX (nitrogen oxides) are emitted from the power plant. The following slides show an example from a Danish tertiary wastewater treatment plant with both P and N removal (Lorentzen 1988).
The graph shows that the treatment plant is able to remove 0,6kg P and about 3kg N per person and year (16).
Conventional wastewater treatment with nitrogen removal

19. Limitations: High Energy Input
Graphics: P.D. Jenssen
The red columns show the emission from the power plant when electricity to operate the watewater treatment plant is generated. More nitrogen oxides are emitted to the air than is removed from the wastewater - in addition about 5 kg of sulphur dioxide is discharged to the air – a gas that is also responsible for the formation of acid rain. Though the figure of gases discharged to the air might be lower today due to stricter regulations, we must still ask ourselves: The problem is moved from water to air - is this sound practice?
The example shows how important it is to have a holisitic approach when designing ecological wastewater treatment systems. Secondary or tertiary effects of the wastewater treatment have to be taken into consideration (16).
Conventional wastewater treatment with nitrogen removal

20. Conventional sanitation systems: Limitations
Source: GTZ (9)
Unsatisfactory purification or uncontrolled discharge of more than 90 % of wastewater worldwide
Severe water pollution, unbearable health risks
Consumption of precious water for transport of waste
High investment, energy, operating and maintenance costs
Frequent neglect of poorer settlements
Loss of valuable nutrients
Problems with contaminated sewage sludge in combined, central systems
Linear end-of-pipe technology
The valuable nutrients contained in human excrement and in wastewater are "eliminated" with high technical and energy inputs in conventional sewage treatment plants. In other words, they are actually destroyed or discharged unproductively into the water bodies.
The substantial energy content of the organic carbon compounds contained above all in faeces is hardly used at all either, not even in state-of-the-art sewage treatment plants. In most cases this energy is simply lost completely.
On the other hand, in order to assure our food production artificial fertilisers are produced with a high energy input, using non-renewable fossil sources. In the case of phosphorus, for example, it is likely that these resources will be exhausted within the next years. On financial grounds alone, if for no other reason, artificial fertilisers do not represent an alternative for developing countries, and they also contaminate the receiving water bodies.
Among other things the enormous investment, operating and maintenance costs of conventional treatment plants make them unsuitable as blanket solutions for developing countries.
Even conventional individual disposal systems, such as latrines and cesspits, make poor alternatives - especially in view of increasing population densities and the substantial groundwater pollution they cause.
The main disadvantage of conventional sanitation systems is their linear character. They represent typical end-of-pipe solutions, transferring and aggravating a number of problems, instead of avoiding them in the first place, and turning valuable resources into pollutants.
Source: (9)

21. Conventional sanitation systems: Summary of limitations
“Our conventional wastewater systems are largely linear end-of-pipe systems where drinking water is misused to transport waste into the water cycle, causing environmental damage and hygienic hazards, and contributing to the water crisis. If we continue to promote these technologies in order to meet the Millennium Development Goals, the overall result could be disastrous as the hygienic situation of our waters would further deteriorate and even more resources would be dissipated and introduced into water bodies.”
Source: (17)

22. Ecological sanitation as a sustainable alternative
Source: (1)
New paradigm is clearly needed:
environmental sanitation based on ecosystem approaches
closure of material flow cycles
Ecological sanitation
based on an overall view of material flows as part of an ecologically and economically sustainable wastewater management system
Respecting local needs and customs
Rather a new philosophy than a technology: substances so far regarded as are seen as a resource now.
The basic principle of ecosan is to close the loop between sanitation and agriculture, although other means of closing flow cycles are also possible.
“In order to reach the MDGs and achieve sustainability in the field of environmental sanitation, a new paradigm is clearly needed. This new paradigm in environmental sanitation must be based on ecosystem approaches and the closure of material flow cycles rather than on linear, expensive and energy intensive end-of-pipe technologies.
Ecological sanitation is such an approach and offers a new alternative to conventional sanitation. It is based on an overall view of material flows as part of an ecologically and economically sustainable wastewater management system tailored to the needs of the users and to the respective local conditions.
It does not favour or promote a specific sanitation technology, but is rather a new philosophy in handling substances that have so far been merely regarded as wastewater and water-carried waste for disposal.
The basic principle of ecosan is to close the loop between sanitation and agriculture, although other means of closing flow cycles are also possible. ecosan systems aim to
reduce the health risks related to sanitation, contaminated water and waste
improve the quality of surface and groundwater
improve soil fertility
optimise the management of nutrients and water resources.”
Source: (1)
Source: (1)

23. between sanitation and agriculture
Agricultural reuse
ecosan systems aim to:
Reduce the health risk related to sanitation, contaminated water and waste
Improve the quality of surface and groundwater
Improve soil fertility
Optimise the management of nutrients and water resources
FOOD
FOOD
closing the loop
between sanitation and agriculture
NUTRIENTS
NUTRIENTS
Pathogen destruction
Source: (4)

24. Closure of the nutrient loop between sanitation and agriculture
Agricultural reuse
Closure of the nutrient loop between sanitation and agriculture
almost complete recuperation of the nutrients, organic material and water
safeguarding soil fertility
traditional agriculture,
Forestry
Aquaculture
market gardening
horticulture etc.
Source: (1)
P. Jenssen
Source: (4)
What is “agricultural reuse” in ecosan?
In ecosan approaches, the basic principle is to ensure a closure of the nutrient loop between sanitation and agriculture, thus ideally enabling an almost complete recuperation of the nutrients, organic material and water that are normally discarded by conventional sanitation systems. This therefore contributes to safeguarding soil fertility and improve its structure and water retention capacity, while decreasing the consumption of finite resources by providing a natural alternative to chemical fertilisers.
In ecosan, the term “agricultural reuse” refers to a wide range of productive, ecosystem oriented, reuse options. This includes reuse in what could be considered as traditional agriculture, i.e. on farmers fields where crops such as cereals are grown, but also forestry, aquaculture, market gardening, horticulture etc. It also includes the reuse not only of nutrients but also of grey water, the organic content of wastewater and energy (1).

25. Other reuse possibilities
Domestic reuse of grey water after treatment:
industry, toilets
Recharge of groundwater
Rainwater harvesting  treatment  drinking water
Use of energy contained in wastewater:
Electricity
Heating
Biogas production (cooking)
Etc…
P. Jenssen
Source: (4)
Other forms of reuse in ecosan
While ecosan aims to close the nutrient loop between sanitation and agriculture through the reuse of nutrients, organics, water and energy contained in wastewater, the reuse options of such an ecosystem approach are not limited to agriculture.
“There are a whole range of other reuse options which can and should be integrated into ecosan systems wherever possible. These include the domestic reuse of grey water, following suitable treatment, for example for flushing toilets, or possibly its use as service water in industry, or used to recharge groundwater. Rainwater use could also be incorporated into this, with rainwater possibly being treated and being used for drinking water. The energy contained in wastewater can be recuperated and put to an array of uses, for example for cooking, for electricity generation, for heating purposes or even for industrial use. Organic material can also be recovered and put to use outside of agriculture, to generate biogas, or perhaps even as a general soil improver.” (1)

26. The Bellagio Principles
Source: (1)
A new approach to environmental sanitation
Environmental Sanitation Working Group of the Water Supply and Sanitation Collaborative Council agreed that current waste management policies and practices are abusive to human well-being, economically unaffordable and environmentally unsustainable.
New Principles:
Human dignity, quality of life and environmental security at the centre of the new approach.
Good governance: decision-making should involve participation of all stakeholders,
Waste should be considered a resource: holistic management
Sanitation problems are resolved in the minimum practicable size and wastes diluted as little as possible.
Clean, healthy and productive living: A new approach to environmental sanitation
“Meeting at Bellagio from 1-4 February 2000, an expert group brought together by the Environmental Sanitation Working Group of the Water Supply and Sanitation Collaborative Council agreed that current waste management policies and practices are abusive to human well-being, economically unaffordable and environmentally unsustainable. They therefore called for a radical overhaul of conventional policies and practices world-wide, and of the assumptions on which they are based, in order to accelerate progress towards the objective of universal access to safe environmental sanitation, within a framework of water and environmental security and respect for the economic value of wastes.
Human dignity, quality of life and environmental security should be at the centre of the new approach, which should be responsive and accountable to needs and demands in the local setting.
In line with good governance decision-making should involve participation of all stakeholders, especially the consumers and providers of services.
Waste should be considered a resource, and its management should be holistic and form part of integrated water resources, nutrient flows and waste management processes.
The domain in which environmental sanitation problems are resolved should be kept to the minimum practicable size (household, community, town, district, catchment, city and wastes diluted as little as possible.”
Source: (2)
Source: (2)
Click directly on the thumbnail to the right to read the Bellagio Principles in full.

27. Advantages of ecosan systems
Improvement of health
Promotion of recycling
Conservation of resources
Preference for modular, decentralised partial-flow systems
Increasing user comfort/security, in particular for women and girls
Contribution to the preservation of soil fertility
Improvement of agricultural productivity and hence contributes to food security
Promotion of a holistic, interdisciplinary approach.
Cyclic Material-flow instead of disposal.
ecosan approaches are based on the systematic realisation of a material-flow-oriented recycling process spanning the full range from strictly low-tech solutions to expressly high-tech solutions. Elements of ecosan systems can range from compost latrines or dehydrating latrines with urine separation to complex, mainly decentralised solutions (see modules M3-1 and M3-2). These may consist, for example, of urine diversion toilets, vacuum transport systems and anaerobic or membrane treatment technology, combined with near-natural greywater treatment, e.g. in wetlands.
Even if ecosan approaches chiefly comprise semi-centralised or non-centralised sanitation systems, they can - especially in urban areas - also be represented by a combination of centralised sewerage systems and downstream sewage treatment plants. However, the treatment technology would then have to be oriented to rendering the effluent hygienically safe instead of to eliminating the nutrients, and the hygienically safe wastewater would then have to be used for agricultural irrigation.
ecosan approaches aim not only at closing the nutrient cycles and rendering them safe, but also at closing local water cycles and minimising the outlay of resources, including the possibility of energy gain. Principally every approach that ultimately leads to closing the loops and to the reuse of nutrients, water and energy should fall under the term ecosan.
ecosan systems offer appropriate and sustainable solutions for different circumstances and demands. They permit acceptable and affordable sanitation for poor and rural areas, as well as for high-income areas and industrialised countries
Source: 18
Ideally, ecological sanitation systems permit the complete recovery of all nutrients from faeces, urine and greywater, benefiting agriculture and minimising water pollution, as well as allowing economical use of water and its maximal reuse, particularly for purposes of irrigation. An even broader understanding of the term could also include the use, storage and infiltration of rainwater, treatment and recycling of solid organic wastes, minimisation of the energy input for wastewater disposal and utilisation of the energy content of solid and liquid wastes (18).
Source: (18)
Source: (18)

28. Advantages of ecosan systems: turning waste into resources
Source: GTZ (18)
Ecosan stands for turning waste into a useful and marketable resource.
A human being almost produces the amount of nutrients that is needed for growing his or her food.
Urine (very few pathogens): 88% of the nitrogen, 67% of the phosphorus and 71% of the potassium carried in domestic wastewater.
Faeces contain 12% of the nitrogen, 33% of the phosphorus, 29% of the potassium and also 46% of the organic carbon – but highly pathogenic
Moreover, ecosan stands for turning former waste into a useful and marketable resource. A human being almost produces the amount of nutrients that is needed for growing his or her food.
Urine hardly contributes at all to the spread of diseases and contains approximately 88% of the nitrogen, 67% of the phosphorus and 71% of the potassium carried in domestic wastewater.
Faeces contain 12% of the nitrogen, 33% of the phosphorus, 29% of the potassium and also 46% of the organic carbon.
If separated, urine can easily serve as a fertiliser and faeces after hygienization as a soil conditioner for agriculture, returning a significant part of the nutrients and trace elements to the soil. However, especially in industrialized countries where urine often contains small amounts of hormones and pharmaceuticals, further research has to be done in order to clarify the situation.
The remaining treated greywater may be used for irrigation and also for recharging the local aquifer. This closes local cycles, helping to improve food security and to conserve soil fertility
The graph on the next page shows the possible reuse of individual substances.
Source: (18)
Source: (18)

29. Advantages of ecosan systems: turning waste into resources
faeces
(brownwater)
anaerobic digestion,
drying, composting,
mixing with organic
solid waste
biogas,
soil
improvement
constructed wetlands, gardening,
wastewater ponds, biol. treatment, membrane- technology
Greywater
(showers, washing,
etc.)
irrigation,
groundwater
recharge or
direct reuse
urine
(yellowwater)
liquid or dry
fertiliser
hygienisation by
storage or
drying
filtration,
biol. treatment
rainwater
water supply,
recharge
treatment
utilisation
substances
The above figure highlights the different reuse possibilities that arise if source separating systems are used. While urine, which is normally hygienically safe can be used after a storage period and without much further treatment, special technologies exist to sanitize brownwater. These are described in module 3-1. Greywater usually also does not exhibit a high degree of pollutions and can, depending on the treatment method chosen, be used in irrigation, to recharge groundwater or even for in-house use. If rainwater is collected, the use of (sometimes scarce) groundwater can be reduced further. The corresponding technologies are all found in module 3-1 (Nutrient Loop) and 3-2 (Water loop).
Source: (1)

30. ecosan - Different Basic Types of Projects
K. Conradin
“ecosan is not only a solution for rural, grass root, small scale projects in developing countries
ecosan projects have proven themselves around the world in a rich variety of applications.
Environmentally friendly settlements in the temperate climates of northern Europe, treating greywater locally and producing fertilizer.
In China: Town of 50’000 people in a suburb of Peking
In Mexico: project in an urban centre with inhabitants just south of Mexico City, began in 2002.
In southern Africa, pre-fabricated dehydration toilets have been available on the local market since 1994, with over of these decentralised units installed world-wide.
“ecosan is often mistakenly seen as being a sanitary solution only useful in rural, grass root, small scale projects in developing countries where a few low cost composting or urine diversion toilets are provided to local farming families. However, whilst a large amount of ecosan experiences do come from such a context, it would be wrong to assume that ecosan is only applicable in this context.
ecosan projects have proven themselves around the world in a rich variety of applications.
Environmentally friendly settlements in the temperate climates of northern Europe have employed closed loop sanitation systems, treating their grey water locally and providing agriculture with fertiliser from urine diversion or from the sludge of biogas plants, as can be seen, for example, in Germany (see picture to the right).
In China, the combined treatment of human excreta and animal manure in small scale biogas plants is common and plans are afoot to provide an ecosan solution for people in a suburb of Peking,
In Mexico, an ecosan programme to address the sanitation needs of the population of Tepoztlán, an urban centre with inhabitants just south of Mexico City, began in 2002.
In southern Africa, pre-fabricated dehydration toilets have been available on the local market since 1994, with over of these decentralised units installed world-wide.
However, even if a similar technology is employed in two ecosan projects, the motivation behind choosing such a system can be completely different, often depending on a mix of factors unique to a given situation. For some it may be a matter of security to have a toilet in the home, or as a status symbol, others may have chosen ecosan simply for reasons of cost, while some may have made a conscious decision to protect the environment. Municipalities may opt for ecosan as part of their Agenda 21 activities, for purely economic reasons, or to protect local water resources.“
Source: (1)
Source: (1)

31. ecosan - Different Basic Types of Projects
Source: (1)
“These examples illustrate that, depending on the technologies chosen and the motivation of the stakeholders, ecosan is a solution for the “poorest of the poor” and the “richest of the rich”.
The mix of different framework conditions, technical options, stakeholders involved and motivations, serves to ensure that no two ecosan projects are alike. For the moment therefore, there is no such thing as a typical ecosan project. However, on the basis of experience gained, it is possible to broadly identify four basic types of ecosan projects, and give a general description of the stakeholders involved, their degree of participation in the process, and the activities to be undertaken. This helps with the identification of the tools and instruments that may be necessary, and who may need them, at different stages throughout the project.
The four broad categories of ecosan projects given here are quite general in their description. Projects in reality may not fit so neatly into one of the categories and individual projects may lie somewhere in between two types. The four basic types are therefore mainly intended to provoke reflection on who the stakeholders in a project might be, what their roles and information needs could be, and what tools should be foreseen to encourage their participation.“ Source: (1)
Project type A: (rural upgrade) Considered as the “classic“ ecosan-project. Farming households, in rural areas, receive support to establish ecological sanitation systems either on their compounds or in their houses.
The farming households are usually responsible for the handling of the recyclates (most often only urine and faeces), using them on their own fields as fertiliser and soil conditioner. Grey water treatment and reuse, rainwater harvesting, and organic waste management can be integrated into the system, although this is rarely practised in this type of project.
Project Type B: Peri-Urban and Urban Upgrade ecosan projects implemented in all existing urban or peri-urban areas of cities and towns in the course of renovation or rehabilitation work. More or less well functioning existing sanitation systems are converted to closed loop systems. Tend to be more complex, because part of “old” systems have to be integrated, and reuse of recyclates has to be taken over by professional service providers, if urban agriculture is not common.
Project type C: (new urban development) Project C is to be found when new dwellings or development areas are being constructed. The dwellings come equipped with ecosan systems, and these systems are therefore considered from early on in the planning stage, facilitating considerably the consideration of all relevant aspects of town planning, land use, (urban) agriculture, water management and so on, as well as their rapid and comprehensive introduction. Reuse of recyclates has to be taken over by professional service providers, if urban agriculture is not common.
Project type D: Non-residential covers all ecosan applications in buildings and areas that are not intended for normal residential use, i.e. public institutions, such as schools or hospitals, private establishments, such as banks or offices, as well as hotels or holiday lodges situated in sensitive areas (e.g. in national parks or on islands), or in regions that are not being served by the public sewer network. Reuse can either take place on site, or can be transferred to another place by a professional service provider.
Source: (1)
The characteristics of the 4 basic types of ecosan project (include greywater in min. resources for rural upgrading)

32. Advantages of ecosan Systems: Closing the Loop(s)
Energy
Water (drinking water)
Nutrient
Filtration (membrane, sand)
Fertilizer (N, P, K)
Grey-water
Black-water
Ground-water recharge
Ecological sanitation (ecosan) is based on a sustainable, source separation system where domestic waste is split in a Water Loop (greywater from sinks, showers, washing) and a Nutrient & Energy Loop (blackwater from toilets, supplied with organic kitchen waste). ecosan can reduce the water consumption by more than 50 percent and facilitate near complete recycling of plant nutrients for agricultural production. The systems can also produce soil amendment and energy from bio-resources. The total cost of the new systems is often lower, because of less need for large centralized sewers. The loops can be organized at household, community or city level (12).
Soil amend-ment
Organic waste
Biologi-cal Treat-ment
Recrea-tional water
Aerobic treat-ment (composting)
Anaerobic treat-ment (biogas)
Watering garden

33. Advantages of ecosan systems: multidisciplinarity
Source: GTZ (18)
ecosan strategies should include interdisciplinary approaches for
raising public awareness,
improving hygiene,
marketing recovered nutrients & applying them safely in agriculture
establishing a service business for building and operating the installations.
Holistic strategies include:
agriculture (especially urban farming)
food security
health care
Economics
urban planning
waste management in general
All in all, ecosan represents a new basic understanding of wastewater handling in which faeces and urine are not considered as pollutants but instead as useful resources.”
“In addition to technical systems, ecosan strategies should include interdisciplinary approaches for raising public awareness, improving hygiene, marketing the recovered nutrients, applying them safely in agriculture, and establishing a service business for building and operating the installations.
Holistic strategies for wastewater management and sanitation include direct links with neighbouring subjects – which are all indispensable parts of closed loops:
agriculture (especially urban farming)
food security
health care
Economics
urban planning
waste management in general
All in all, ecosan represents a new basic understanding of wastewater handling in which faeces and urine are not considered as pollutants but instead as useful resources.”
Source: (18)
Source: (18)

34. Conclusion Leapfrog the conventional centralized sewers -
go straight to modern sanitation based on ecological principles!
J. Heeb
P. Jenssen
R. Otterpohl
Source: P. Jenssen

35. END OF MODULE M2-1 seecon FOR FURTHER READINGS REFER TO M2-1 TUTORIAL
(1)
J. Heeb
K. Conradin
END OF MODULE M2-1
FOR FURTHER READINGS REFER TO M2-1 TUTORIAL
Dr. Johannes Heeb, International Ecological Engineering Society & seecon international
Prof. Dr. Petter Jenssen, Department of Mathematical Sciences and Technology, Norwegian University of Life Sciences
Dr. Ken Gnanakan, ACTS Bangalore, India
Katharina Conradin, seecon international
© 2006
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36. ++ References
Werner, Ch. Panesar, A. Bracken, P., Mang, H.P., Huba-Mang, E. Gerold, A.M., Demsat, S., Eicher, I. (GTZ) (2004): An ecosan source book for the preparation and implementation of ecological sanitation projects. 3rd draft, February GTZ.
Environmental Sanitation Working Group of the Water Supply and Sanitation Collaborative Council WSSCC (2004): Bellagio statement: Clean, healthy and productive living: A new approach to environmental sanitation.
Evans, B. (2004): Whatever Happened to Sanitation? - Practical steps to achieving a core Development Goal. Millennium Project: Task Force on Water and Sanitation in March 2004.
Werner, Ch., Mang H.-P., Klingel, F. Bracken, P. (2004): General overview of ecosan. PowerPoint-Presentation. Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH ecological sanitation programme.
Evans, R. (1990): Tod in Hamburg. Stadt, Gesellschaft und Politik in den Cholerajahren Rowohlt.
Ecosanres (2005): Fact Sheet No 1: The Sanitation Crisis. Ecological Sanitation Research/SIDA, Sweden. Available at: (Accessed ).
NOVAQUATIS, EAWAG (2005): Nova 5 Workpackages: Micropollutants. Available at: (Accessed ).
Encyclopaedia Britannica Online: Eutrophication (Accessed )
GTZ: ecosan – Ecological Sanitation: Shortcomings of conventional sanitation systems. Available at: (Accessed ).
Deplazes, G. & Hieber, M (2005): Handlungsbedarf beim Abwasser im ländlichen Raum. – In: Schweizer Gemeinde 10/2005.
BUWAL Bundesamt für Umwelt, Wald und Landschaft (2005): (accessed )
Alsén, K.W. & Jenssen, P.D. (2004): Ecological Sanitation. For mankind and nature. Norwegian University of Life Sciences.
Encyclopaedia Britannica Online: Runoff. (Accessed )
Ecosanres (2005): Fact Sheet No 2: The Main Features of Ecological Sanitation. Ecological Sanitation Research/SIDA, Sweden. Available at: (Accessed ).
Esrey, S. A., Andersson, I. Hillers, A., Sawyer, R. (2001): Closing the Loop. Ecological Sanitation for Food Security. Publications on Water Resources No. 18. UNDP, SIDA.
Jenssen, P. D. (2005): Ecological Sanitation – a technology assessment. Norwegian University of Life Sciences. PowerPoint-Presentation, held at the 9th. International conference on ”Ecological Sanitation” Mumbai India, November 25th, 2005.
Werner, Ch., Abdoulaye Fall, P., Schlick, J. & H.-P. Mang (2003): Reasons and principles for ecological sanitation. 2nd International Symposium on Ecological Sanitation, April Lubeck, Germany. Available at:
GTZ: ecosan – Ecological Sanitation: Advantages of ecosan concepts. Available at: (Accessed ).
Werner, Ch. (2004):Ecological sanitation – principles, urban application and challenges. PP-Presentation at the UN Commission on Sustainable Development, 12th Session - New York, April Available at: www2.gtz.de/ecosan/download/CSD12-ecosan-werner.pdf

37. ++ Abbreviations ACTS Agriculture, Crafts, Trades and Studies
CSD Commission on Sustainable Development
GTZ German Agency for Technical Cooperation
MDGs Millennium Development Goals
N Nitrogen
P Phosphorus
SDC Swiss Agency for Development and Cooperation
WSSCC Water Supply and Sanitation Collaborative Council

38. ++ Glossary: Greywater
Greywater is only slightly polluted wastewaters from dishwashing, showers, laundry machines, water from sinks etc. Greywater makes up for the largest share of wastewater.
Yellow water is either urine diluted with flushwater or pure urine. Urine contains most of the nutrients we excrete again, but only has a very low, if at all, pathogen count. However, we also excrete micro-pollutants or endocrine substances through urine.
Brownwater refers to faeces mixed with (flushing) water, but no urine. Most of the pathogens are contained here.
Blackwater is urine and faeces mixed with or without domestic wastewater from showers, washing machines, sinks etc.
GREYWATER
Own source

39. ++ Glossary: Micropollutants
“Micropollutants refers to pollutants which usually appear in very small amounts in the environment. In the case of wastewater, one mostly refers to substances such as pharmaceuticals and synthetic or natural hormones (the latter are also called endocrine substances). These substances have a negative effect, especially if they are released in water bodies, as they can influence the sexual development of animals living in the water.
Moreover, some pharmaceuticals can also accumulate in the body fat tissue, and can thus eventually pose a threat to human beings again, as they are feeding at the top of the food web.” (7)
MICROPOLLUTANTS

40. ++ Glossary: Eutrophication
“Eutrophication refers to the gradual increase in the concentration of phosphorus, nitrogen, and other plant nutrients in an aquatic ecosystem such as a lake, a pond, or also rivers (though the risk is higher if is a standing waterbody). The productivity or fertility of such an ecosystem increases as the amount of organic material that can be broken down into nutrients increases. This material enters the ecosystem primarily by runoff from land that carries debris and products of the reproduction and death of terrestrial organisms. Moreover, cultural eutrophication occurs when man speeds up the aging process by allowing excessive amounts of nutrients in such forms as sewage, detergents, and fertilizers to enter the ecosystem. Blooms, or great concentrations of algae and microscopic organisms, often develop on the surface, preventing the light penetration and oxygen absorption necessary for underwater life. In the end, the algae might consume so much oxygen and sunlight that all other aquatic life deceases.” (8)
EUTROPHICATION