Hi, Chris.
Some of the details are not worked out in the small sketch.
To answer your observations.
1. The solar on/above the roof is PV as one needs electricity for a heating element in the base of the biogas reactor to create thermophilic fermentation. This will substantially speed up the digestion and allows the reactor to remain small and yet discharge pathologically purified effluent.
1. The solar drier is to dehydrate the liquid effluent to make dry compost. This requires quite some space and can be a small business outside: transport, drying, packing from many units is more efficient than each for itself. The roof space is needed for hydroponic vegetable growing.
2. Grey water and urine can indeed be used in the roofgarden and facade gardens. I would imagine that grey water is preferred and urine is cristallized off-site also as a business.
3. The kitchen waste and woodfibre toilet paper are required to balance the C/N value of the slurry for optimization of gas output. Once the faecal matter has gone through the double biogas reactor under thermophillic conditions it is phatologically clean. One can apply the slurry also directly to agriculture. Further sundrying of the effluent (outside the village) will produce transportable bags of compost.
4. If someone will implement the proposal I will work it out.
5. Biogas operation is in the groundfloor (compartments) only. From the upperfloors the piping goes down.
I worked three years in biogasprojects.

Hi Sjoerd,

Thanks for your urban concept drawing. My favorite aspects of it include the plants growing on the outside of vertical walls and the use of solar driers.

Please allow me to make a few comments and suggestions.

1. Why not put the solar drier (or oven) on the roof to economize space on the land?
2. The vertical garden could receive a percentage of the urine and greywater.
3. I would not prefer to mix toilet and kitchen wastes, to keep the fecally dangerous material as small as possible. This mixing could happen after the feces are made safe by one method or another.
4. Some of the features are hard to understand, so it may be good to make a clearer draft, possibly including an accompanying text with explanations.
5. How can the biogas operation be in the penthouse?

Best wishes,
Chris Canaday

Related to urban processing of human excreta and kitchen waste and the production of fertilizers for food security, I feel that a compact construction design is needed which can be fitted into existing buildings (floor height up to 240 cm). The unit needs to process the excreta and kitchen/food waste and produce biogas (cooking) as well as urine and pathogen free slurry. The combination of shredded kitchen waste, human faeces and carbon fibre toilet paper for dry anal cleaning will improve the biogas output. All families in the same building need to use the unit. Solarpower from the roof can speed up fermentation. Since in urban environment people live in 4-5 stories high, the unit can be constructed in the groundfloor, while the roof is used for rainwater collection, further composting, vermiculture and hydroponics. Part of the grey/rain water can be used in the hydroponic foodproduction.
Given the large numbers of suburbans that need to be upgraded, commercial production of the unit may be feasible when made and installed in smaller components that fit into existing buildings. See sketch.

The latest version of the WG5 factsheet is more focussed on the rural housing setting and the possibilities for composting etc., than on the urban situation. The urban application is often limited by established thinking of public functionaries and restrictive legislation. On the other hand, more people will live in the future in urban areas than in rural areas. The factsheet can include possible changes required in the more urban environment, including reconstruction of buildings to accommodate UDT and UDDT, or biogas production that will produce safe-to-handle fertilizers. Vermicomposting or vermiculture is a process that produces concentrated fertilizer from compost, but is not mentioned in the factsheet. The concentrated compost can be used in decorative house plants (urban), hydroponic gardening including rooftop gardening (urban) and as fertilization in greenhouses (cold climate urban areas).

It is an very great idea to re-use old flowers! When it comes to sustainability a lot of people tend to forget how much waste it can cause to order flowers via florists uk and then just toss them though you can do so many more productive things with them.

In facsheet WG5 version December 2011 the following:

The Biogas reactor option for sanitation waste treatment should be included again. In rural Nepal (www.bspnepal.org.np) and India (www.biotech-india.org)+(M.Naufel www.bioenergysystems.in) linkage of house toilets to the biogas reactor is becoming more common ; probably also in China. With adequate retention period the patogens are greatly reduced and handling of the effluent is safe for agricultural purpose. In Nepal the effluent is co-composted with agricultural waste before application on land. In India human excreta based biogas reactors are in use. Adjusting the high Nitrogent content of human excreta can be corrected by adding shredded kitchen waste, having a higher Carbon content; this works best with pour-flush UDTs. Developing biogas for human excreta should be stimulated as it solves both part of the fertilizer and urban energy problems.

In the WHO figure #7, under barrier 1 possibly "transport" can be added.
In urban areas many people buy processed food. Where does this fit in?, or is a new barrier X required?.

Related to food production with wastewater the term 'hydroponic' has not been mentioned, but can be linked with urban (rooftop) agriculture.

Dea Elisabeth,
Reactive nitrogen is ammonia, ammonium, nitrate, nitrite and nitrous oxides, NO and NO₂. If I remember correctly, Rockström et al. worries mostly about too large emissions of nitrate being able to make also the oceans to become eutrophic and flip (i.e. to become anaerobic). This is better spelled out in their article in Nature: (Nature 461, 472-475 (24 September 2009) | doi:10.1038/461472a; Published online 23 September 2009, www.nature.com/nature/journal/v461/n7263/full/461472a.html) They do however also mention the problems with nitrous oxide and the climate effect, but I do not remember that they explicitly mention the gas emissions of NH₃, NO and NO₂ are involved in forming particles (smog) hazardous to human health, but their wording indicates that they have had this also in mind. These particles related to NH3, NO and NO2 are Europe estimated to have quite a negative impact on health. In economic terms the negative impact of nitrogen, which mainly consists of the health hazard, is smaller, but of the same order as all the advantages of nitrogen fertilizers used in European agriculture(European nitrogen assessment).
All the best,
Håkan

Dear all,

Here is another great factsheet coming up, thanks to the work of Robert Gensch and all the other co-authors and contributors. We are still making some last minute changes but I wanted to give you a chance to see it before it is published, so below you find the current version (in case anyone feels inclined to make comments in the Word document let me know and we can send it). But we are on the last stretch as the factsheet compilation is due to come out by Christmas.

Anyhow, there is one paragraph that I do not understand:

Only nitrogen can be extracted from the surrounding air but the industrial process is likewise energy-intensive and today strongly based on fossil fuels. Human activities now convert more nitrogen from the atmosphere into reactive forms than all of the earth´s terrestrial processes combined (Gruber and Galloway, 2008). This is four times the rate proposed as the planetary boundary for human modification of the nitrogen cycle, in order to avoid large-scale ecological impacts (Rockström et al., 2009). This indicates a double driver for excreta reuse - to reduce fossil fuel use and to reduce the input of reactive nitrogen in ecosystems.

I also checked the cited Rockström reference but could not grasp what is going on:
Rockström, J. et al. (2009) Planetary boundaries: Exploring the save operating space of humanity, Ecology and Society, 14(2), Art. 32, www.ecologyandsociety.org/vol14/iss2/art32/

Can someone explain to me in simple terms what the problem should be with reactive nitrogen in ecosystems? Or is just referring to ammonia and nitrate polluting water sources, and using complicated wording?

By the way, Hakan Jönsson suggested that nitrogen reuse would even have a triple driver where the third one is reduce emissions of greenhouse gases.

If anything is unclear for you in the factsheet, feel free to put it here.

Actually, I do have a second question: it comes from the gender factsheet (working group 7b) but it fits to the reuse group.

Does anyone know the right reference to cite for this sentence? We don't know anymore which IFAD reference was meant:

Worldwide, women own just 2% of all land (IFAD, 2008).

Edit on 6 January: this has in the meantime been investigated by Pay Drechsel, see his answer here: forum.susana.org/forum/categories/60-wg-...der-factsheet-7b#829

And here is my third question:
About the issue of phosphorus shortage, the factsheet now says this:

How long the respective phosphorus and potassium reserves will still last is disputed as estimates depend on many factors, like the potential discovery of new reserves, increasing population growth and demand, increasing difficulty to extract reserves, and related market price developments (Cordell et al., 2009; Van Kauwenbergh, 2010; UNEP, 2011; USGS, 2011).

I am wondering if it would be worth mentioning in one sentence that increasingly, lower quality phosphorus will be mined (contaminated with uranium, which is radioactive) and that the phosphorus fertiliser prices are bound to go up over time due to the fact that the easily accessible phosphorus mines will be depleted (if I understood right).

Kind regards,
Elisabeth

Dear all,

Please find attached the final draft version of the SuSanA WG 5 fact sheet on food security and productive sanitation.

I would like to use this opportunity to thank all of you for the valuable feedback and inputs we received during the last weeks. We tried hard to consider all your feedback, however, due to the fact that we had to squeeze everything onto 8 pages we were probably not able to include all the bits and pieces satisfactorily, so kindly bear with us.

Any final feedback and comments are still welcome and can be send either via the WG5 mailing list (This email address is being protected from spambots. You need JavaScript enabled to view it.) our through the SuSanA forum until November 18 at the very latest.

Thanks again and looking forward to your final feedback

rob#




Robert Gensch

German Toilet Organization
Mobile: +49-(0)-15734324412
Email I: This email address is being protected from spambots. You need JavaScript enabled to view it.
Email II: This email address is being protected from spambots. You need JavaScript enabled to view it.
Skype: robertgensch

Dear all,

I just thought I would post here the current version of the updated factsheet: Several people have in the meantime included their comments in the Word document. This has happened via the mailing list of WG 5 (which people find more convenient when it comes to sharing commented Word documents).

The attached file includes the comments of Arno Rosemarin, Philipp Feiereisen, Linus Dagerskog, Cecile Laborderie, Martina Winker and Robert Gensch. I love the way these factsheets become a collaborative effort of a quite a few SuSanA partners!
It is not yet too later to include your comments! Please send them as soon as possible. Time is running out, we should slowly begin to wrap it up and squeeze it all back to 8 pages (the 2-column format will help).

Oh and if you wonder about the mentioned mailing list: each working group has a moderated mailing list, whereby you can send an e-mail to This email address is being protected from spambots. You need JavaScript enabled to view it. and with a short time delay (the moderator checks the e-mail), it will be delivered to all working group members (for most working groups, this is about 300 people or so). To get onto such a mailing list, ensure in your SuSanA login settings you have put a tick at the right working group. See here: www.susana.org/lang-en/your-details

If you have the feeling that something is not working with this mailing list, contact the working group lead (see their e-mail address on the SuSanA website under working group) or the secretariat on This email address is being protected from spambots. You need JavaScript enabled to view it..

Regards,
Elisabeth

Dear all,

Please find attached a first attempt to revise the current WG5 fact sheet version. The structure has been slightly changed. However, it still contains the old text blocks in the respective chapters (that in some parts still need rephrasing and shortening) plus additional comments and suggestions where further input is needed (highlighted in yellow). In addition it contains suggestions of names/organizations for each chapter, hoping that those persons/organizations can take over the responsibility for the said chapters (or at least support and contribute to the further development of those chapters).

Please note that the current doc version is just a working document which is not yet layouted and formated in order to allow for easy changes and editing in track change modus.

The currently suggested structure of the fact sheet is as follows:

- Executive Summary (incl. key take-aways, 1/2 page)
- The Link Between Sanitation, Agriculture and Food Security (meant as introductory part that shouldn't be longer than 1 1/2 pages max)
- The Productive Sanitation Approach (2 pages max, including small boxes for best practice examples that should fit on half a page altogether)
- Urban and Periurban Agri- and Aquaculture (1/2 page)
- Institutional and Legal Aspects (1/2 page)
- Business Opportunities (1/2 page)
- Public Health Implications (1 page)
- Future Challenges (1/2 page)
- References/ Further Links & Literature/ Authors (1 page)

I would like to encourage all of you to have a closer look at the current draft and provide your feedback and inputs by October 12, 2011 at the very latest on the following:

1. Current structure
2. Chapters you could imagine to actively contribute to
3. General comments and constructive feedback on the current version (e.g. what is missing, which figures need updating etc.)
4. Best practice examples you would like us to include in the fact sheet (in small boxes)
5. Further reading material and links you would like us to include in the further reading section
6. Pictures and figures you would like to see in the document
7. Concrete commitment to take over the drafting of specific chapters


As to taking over responsibilities for certain chapters - as a first shot - I would like to propose the following:

Urban & Periurban Agri- and Aquaculture --> RUAF
Institutional & Legal Framework --> SEI/Linus Dagerskog
Public Health implications --> GIZ/Martina Winker

This is just a suggestion and I am looking forward to your feedback, particularly from the mentioned persons and organizations.

Any further inputs and commitments from all other WG5 partners are of course highly appreciated.

Thank you very much in advance and looking forward to your timely feedback

rob#

Dear all,

Thank you very much for your valuable comments and suggestions so far. Based on the comments in this forum and some individual feedback I received via email during the last weeks I do belief that there is a need to restructure the current fact sheet version before we actually enter into rewriting certain identified chapters.

I will circulate a revised version (with a general structure suggestion) in the coming days for your feedback and comments and would highly appreciate if meanwhile some more WG members could indicate if they would be willing to take over a more active role in reviewing/rewriting some of the chapters in the coming weeks.

And maybe as an additional incentive: Those willing to actively contribute to this fact sheet awaits being listed as official authors of this publication. So don't hesitate

Thank you very much in advance and best regards

rob#