Sustainable Sanitation for flooded areas

  • dorothee.spuhler
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Sustainable Sanitation for flooded areas

Dear all,
I am looking for experiences of sustainable sanitation designs for (permanently) flooded areas. I find a nice document from Michael Brown presenting their floating UDDT design in Cambodia , but I don't have his contact.
Is there anyone having a particular experience/documents to share on sustainable sanitation designs (i.e. toilets) in such areas?
Best Dorothee

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  • mwink
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Re: Sustainable Sanitation for flooded areas

Dear Dorothee,

Robert Gensch and his team published recently a nice broschure on "Low-cost sustainable sanitation solutions for Mindanao and the Philippines" which also included a solution for costal areas with flooding events.
For details check this link, pp. 43:

Yours, Martina.

Research unit Water infrastructure and risk analyses
Institute for Social-Ecological Research (ISOE)
Frankfurt, Germany

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  • robhughes
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Re: Sustainable Sanitation for flooded areas

Dear Dorothee,

I'm managing the project Michael Brown and Judy Hagan's presentation was about, and would be more than happy to share our info and experiences with you - my email is This email address is being protected from spambots. You need JavaScript enabled to view it., while theirs are This email address is being protected from spambots. You need JavaScript enabled to view it. and This email address is being protected from spambots. You need JavaScript enabled to view it..

We've been working for a few years on sanitation in floating communities and our work will be replicable to many other situations. We've developed designs for these extra-constrained environments which would be easily replicated and adapted, and this will be of great benefit to floodprone areas too.

I've attached some links below as a start. The bottom link should have the presentation audio:

My connection is very bad at the moment, but I will aim to upload a recent presentation soon.

Looking forward to discussing further with you

Rob Hughes
Project Manager, Engineer
Live & Learn Environmental Education, and
Engineers Without Borders Australia

Rob Hughes,
WASH Manager,
Live & Learn Environmental Education
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  • muench
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Re: Sustainable Sanitation for flooded areas

Dear Rob,

Thanks a lot for these links. I just viewed the little YouTube Video and must say, it is really nice and informative, thanks!

For those with poor internet access, I have also uploaded the plain powerpoint presentation about your project from the WASH conference in Brisbane to the SuSanA library here:

And now here come my questions (after viewing the video and reading your presentation and the report from Oct. 2010):
  1. Why did you decide to build the squatting pan in concrete (rather than use existing plastic or ceramic versions)? Isn't the concrete version very heavy? How did you provide a smooth finish to the concrete?
  2. The setup looks a little bit shaky to me and my question is: do elderly people or highly pregnant women find it difficult to use it?
  3. How many of these toilets are in use to far and is there any sign of replication? The report mentions (only) 14 toilets.
  4. What incentive do the "normal" people in these floating communities really have to bother with such a toilet (which needs to be emptied and cared for), compared to the status quo, which is simply shitting directly into the lake? (apart from the few "enlightened" people who care about environmental pollution or really want to change the hygienic situation)
  5. I assume that shitting into the lake used to be pretty much OK, before there was population growth and now too many people are doing this. Am I right in this assumption?
  6. Have you had any dealings with the Cambodian government (at any level) about this, and what was their reaction? Actually your longer report from Oct. 2010 (Dorothee gave the link above) mentions Ministry of Rural Development. Please tell us more how you cooperate with them; what was their idea how to solve this problem before you came along?
  7. Do the people in these communities value fertiliser, do they normally buy it? Do they do any farming (where?)?
  8. What are you up to right now and what is planned in the near future? In which way is Engineers without Borders Australia and the local NGO Live and Learn working together - does all the funding come from EWB?
  9. How much does the bucket with faeces smell (when you open the lid), given that the toilet design has no ventilation system for the faeces and hence they can't dry out.
  10. Is there any odour lock mechanism on the urine collection, or is it not necessary?
  11. what gave you first the idea to go down the urine separation route as a solution to your problem (just curious)?
Looking forward to your answers - very interesting project!


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  • robhughes
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Re: Sustainable Sanitation for flooded areas

Hi Elisabeth, great questions and thanks for asking them.

1) The material of the pan was a key question and difficulty early on. The simple answer was this was the only practical option to make locally, and certainly cheaply. We considered many options including imports and making them from wood, plastic, ceramic, and fibreglass, but none of these (or the skills to make them) were available or suitable. However - we are now working on fibreglass models due to the arrival of fibreglass boats and skills related to that, and always seeing how we can improve the pans!
Concrete is the most common manufacturing technique to make pans like this at the moment here. The concrete is certainly heavier than the other materials, and weight is a massive concern on floating houses! We worked hard to make it light yet durable, and tested how it has been received. Currently we're looking at about 30kg for the pan and the whole system is much smaller and lighter than most designs. For the surface finish - a two-step process using cement powder and some manual smoothing does the job and there aren't real problems with absorption etc. We're experimenting with molds to see if we can reduce the labour input.

2) There are a few issues with access - particularly for the elderly. For a start we were aiming at demonstrating it with the majority and then diversifying designs for different needs. We are working on support frames with steps to help with access, and have considered systems that can be cut into the floor to lower the pan - however there are a few drawbacks with little space below the floor and then added installation efforts/costs (which are very low now), as well as access to the collected waste itself and handling requirements.

3) We started with a small pilot of 14 (in field) to test the concept, and at the moment we're preparing to expand a lot. We've built more and are training suppliers and developing a more efficient production technique - aiming to launch it as a product soon. A couple of partners have come on board recently to help expand the program.

4) The incentive question is a good one, we were very conscious of this throughout the design process. The main incentive is agricultural and we've already had users applying the treated waste to their dry season crops. The communities are dependent on depleting fisheries and crying out for alternative income sources so there is strong impetus for this. Also, on the lake the connection between where you and your neighbours shit and where you drink from is quite direct and some awareness already present. As we expand and launch the program we'll be doing more demand creation work and looking for social incentives.

5) I think your assumption is generally right - population is possibly exacerbating this, but it's also a traditional understanding that water quality gets worse in the dry season (and some people travel further from their houses to collect water)

6) Yes we report regularly to the Ministry of Rural Development as well as working with the local community (the village chief is a toilet user and supporter). Early work was funded by UNICEF and MRD and they were both supporters of developing a solution for floating communities. It was an unaddressed issue before we looked at it, floating communities around the world are often the most neglected and marginal, and people are often focused on the 'easy' ways to get numbers of toilets.

7) There is currently little agriculture in floating communities - most catch fish. But there is some dry season cropping when they get access to land, and a handful have home gardens. As I said there is a lot of interest in more agriculture and we've been working on this too - including adapting floating gardens similar to bangladesh. There is a high demand for fertiliser in nearby land-based farming communities so we want to tap into this market as well.

8) Right now we are working with a couple of partners to establish local, mass production, and once the supply is in place increase the demand creation to expand the coverage, including into other communities particularly in floodprone areas. We're also working on agricultural trials and reuse aspects.

We have another related project around floating biodigesters... this is also targeted at floating houses but in conjunction with floating pig farms that are popping up around the lake. The incentives for this one are extra fertiliser and biogas for cooking, instead of pig shit in the water!

EWB Australia supports Live & Learn mainly through supplying an in-country field volunteer (myself), and linking the project to technical support through engineering networks. EWB has partnerships with a number of NGOs and aims to respond to their needs for technical support etc. No money from EWB goes direct to the project, and the project funding comes mainly from grants.

9) The smell from the buckets is quite little and doesn't cause any problems (people expect a bad smell and are happy there isn't one). We try to emphasise adding enough dry (powder) ash to dry the waste out - while there is sometimes some condensation inside the buckets when we open them the treatment stills seems to work well.

10) We suggest an odour lock (a cut condom) only when collecting the urine - when it is piped directly to the water it can be washed down with a small amount of water.

11) Urine separation was particularly attractive to reduce the weight and volume of the collected waste and the system as a whole, reducing costs and installation requirements and fitting the physical constraints. We also wanted to give people the option of using it as fertiliser to increase the incentive for usage. We've started looking at 2-hole systems (liquid separation but combining urine and wash water), for smaller, cheaper systems for those with small houses and not wanting to collect urine.

I hope these answers are adequate! Let me know if you have more.


Rob Hughes,
WASH Manager,
Live & Learn Environmental Education
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  • tmsinnovation
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Re: Sustainable Sanitation for flooded areas

Hi Dorothee

Have a quick look at this case study:

And you could contact Antoine Delepière the author, he could provide you with some interesting insights on sustainable sanitation for flooded areas, after working in the aftermath of one cyclone and withstanding the second cyclone during the project.

Kind regards

Trevor Surridge
Sanitation Advisor
GIZ Water and Sanitation Program
German Development Cooperation

GIZ Water Programme office
Chaholi Rd. No 5, Rhodes Park
Private Bag RW 37x
Lusaka, Zambia
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  • asej
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Re: Sustainable Sanitation for flooded areas

Oxfam in Bangladesh has experience of this - contacts are: Abdus Sobhan – This email address is being protected from spambots. You need JavaScript enabled to view it.; Golam Morshed – This email address is being protected from spambots. You need JavaScript enabled to view it.

They published in Waterlines Vol 29, no 3 in 2010 an article on the topic and a bit more. I have attached the article if you dont already have it.


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Researcher “SPLASH urban sanitation in Maputo” and “WASH & RESCUE - WAter, Sanitation and Hygiene in RESilient Cities and Urban areas adapting to Extreme waters”
Co-lead on “SuSanA working group 8 in sanitation in emergencies” see Blog:

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