Mobile Sanitation Services for Dense Urban Slums - project re.source (Stanford University, USA and SOIL Haiti)

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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

I love this approach and I think I understand the context in which it will work. We are discussing a form of replication location in Uganda and India. I realize you may be still at the development stage, but I wonder if you have any indications so far on -

1 The viability of the collection, composting and reselling process can be troublesome. Transport for collection is usually one of the larger costs components and the more money that can be made from reselling the humanure / vermicompost the better. This is a tough market with low margins, but how are the economics stacking up to date?

2 If I was a customer I can see the advantage of a box and taking control over my families excreta management and the privacy and dignity this brings. However, if I was poor and wanted to save money, I would also be tempted to dump the bucket in the local river and avoid the collection service charge. Have you noticed this as problem?

3 Have you thought of Black Solder Fly larva for processing. They love fresh shit and have real value. Also wood ash capture for the nutrient in the urine?
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Good questions by Steve, looking forward to Kory's reply.

The purpose of my post today is to provide people who don't have access to Youtube videos with a quick overview of what Kory presented and the questions that followed during the third webinar that SEI organised on 7 November (see Arno's post about it here: forum.susana.org/forum/categories/139-ge...g-now-available#6312 ).

Kory was the third presenter. His presentations starts exactly here in the Youtube video:



Mobile Sanitation Services for Dense Urban Slums
by: Kory Russel, Stanford University, Stanford, USA

Location of research: With SOIL in Haiti

The short presentation that he used for the webinar:

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Some important points from his presentation:
  1. The mobile toilet costs 75 USD (locally produced). (my question: that's not so cheap? Is there a cost-breakdown available?)
  2. We are working on a scalable design - to cost 30 USD, made of concrete (won't this be too heavy though?).
  3. There was initially a free trial period, where users didn't have to pay.
  4. SOIL later phased in monthly payments (still operating today) (would be good to know details of their payment collection scheme; if someone fails to pay, is the toilet taken away again? This is how Sanergy does it.)
  5. Low monthly fee, no upfront costs.
  6. There is currently a waiting list of 550 households who want to get such a toilet. There is a strong demand for a pleasant, convenient, aspirational toilet; with a service that is professional and reliable.
  7. This was funded via a GCE Phase 1 grant by the Bill & Melinda Gates Foundation; we are hoping to get a Phase 2 grant.
  8. The aim is to reach the poorest households, and to fill the gap which public toilets cannot provide (dangerous at night), or where pit latrines fail (e.g. when there is flooding).
  9. Working in illegal/informal settlements; high turn-over of people.
  10. We wanted something that's with the user throughout the entire sanitation experience (i.e. also emptying and transport and reuse - the whole chain).
  11. Cartridge based system (container based).
  12. The content is taken to outside of the community, SOIL has a composting facility, where soil amendment is made from it (could create a secondary stream of revenue).
  13. User-centred design
  14. Tracking of all waste streams
  15. Started 2011.
  16. In India there is a legal framework (ban on manual scavenging) which could prohibit a solution like this (see also this discussion on the forum about it: forum.susana.org/forum/categories/39-mis...man-waste-scavenging )
  17. Aim is for a mass-producable product design.

Questions from the audience:

(1)
Question by Dorothee Spuhler:
Can this be funded completely from the monthly user fees only? Or do you need to generate second revenue stream from the compost?

Answer by Kory:
Other organisations such as Sanergy* (Kenya), X-runner (Peru) and Clean Team (Ghana) are managing to cover all their costs from the user fees but in our project we are not yet there, because we are dealing with the poorest of the poor. Having back-end products which could be sold would help.

* Comment by me: Laura from Sanergy told me in October that the user fees also don't cover all their costs. To become totally subsidy-free they are banking on being able to sell the by-products, mainly compost and they are also aiming to sell biogas, she told me. But they are not yet there either.

(2)
Question by Francis de los Reyes:
Is this type of toilet really "aspirational"? Wouldn't the people only see a water flushing system as "aspirational"?

Answer by Kory:
No, you don't have to have a water flush to have an aspirational toilet... The users are "flushing" with dry covering material instead of water. And instead of water moving the excreta awway, it is done by a professional service provider.

(3)
Question by myself:
Why do you have this long waiting list of 550 households? Why can you (or SOIL rather) not meet this demand?

Answer by Kory:
We don't want to scale up too repidly because there could be a danger of diminishing performance. We want to remain reliable, keep their trust; therefore we are doing a slow scaling up. We still need more suitable tools for scaling up; need to create a framework.

(4)
Question by Mark Illian:
Can you use these toilets in IDP camps for displaced people in Haiti (IDP = internally displaced people)?

Answer by Kory:
In principle yes; we are collaborating with Sanivation in Kenya; but it's a logistical challenge, we are not yet ready for such difficult conditions.

(5)
Question by Mark Illian:
Could you say more about the sludge (excreta) treatment & disposal?

Answer by Kory:
The cartridge from the toilet is sealed and removed when full. It is taken to SOIL's composting facility outside of the community, where it is composted thermophilically at 170 Deg F (= 77 deg C). The end product is sold to reforestation projects or for boutique gardening (so you already have a secondary revenue stream? But I guess this compost is not solely from these toilets but also from others?). The containers are washed, sanitised and put back in circulation.


That's it from the webinar presentation & questions. I hope this post was useful for you if you are interested in this approach in Haiti. If you found my efforts here with this post useful, please let me know by responding or by clicking on the "I like this post" below (or increase my karma points on the left by clicking on the plus symbol ;-) ). It's always nice to know if it was worth my time to write this out. (this of course applies to anyone who makes detailed posts for the benefits of others)

Regards,
Elisabeth

P.S.
This seems to have been an excellent cooperation between Standford University and SOIL in Haiti. More about the onling work with this on the SOIL website:
www.oursoil.org/local-contractors-take-o...d-toilet-production/

SOIL told me on twitter that about 2600 people are now using such toilets. I asked them how many people share one toilet. The answer was "the number comes from a combination of household toilets and communal toilets shared by 4 families".

A photo of the inside of the toilet from SOIL on Twitter:
pbs.twimg.com/media/BY4FZ1hCEAADe5c.jpg:large



Another photo of the toilet showing the urine diversion:
pbs.twimg.com/media/BY0ZPpOCYAAqB5C.jpg



SOIL is very active on Twitter and responds to questions there very fast: @SOILHaiti

Second P.S.
This is essentially a single vault urine-diverting dry toilets, which comes with the pros and cons of single vaults mainly in terms of hygienic safety during the handling of the excreta (see also here on the forum: forum.susana.org/forum/categories/34-uri...re-the-pros-and-cons ). For this type of application (mobile systems for low-income areas), single vaults are indeed a suitable option in my opinion.

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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Hi everyone, This is Sasha Kramer from SOIL. We were sorry to miss the webinar the other day but excited to see all the buzz it has generated and grateful to our colleague Kory Russel for his great presentation of re.source's collaborative work with SOIL. I wanted to take a moment to respond to some of the questions I see in this post to the best of my ability.

Cost of the toilet model: Kory mentioned that it is currently $75. We have some good news which is that we have been able to bring the cost of the wooden model down to $50 and our cement models cost less than $30 USD (see image below), all made of local materials. Although we have been able to bring the cost down the toilets can be challenging to keep clean because of the materials and we are looking forward to testing the plastic models that re.source is working on as well. Our goal is to be able to provide our customers with as many toilet design options as possible so that they can choose a model. Since they all operate with the same service system it is not a a problem to have a wide variety of models out there.



Concrete design: This is indeed heavy, but still portable, it just takes more effort and care than the wooden one and would not be as easy to move around often.

Payment collection scheme: People have a three month grace period to pay before their toilet is taken away. They receive a bill each month and on the third month of non-payment the toilet will be removed. We do try to meet with people individually before taking away the toilet.

Cost recovery through user fees: We are getting there. Preliminary estimates show that the fee of approximately $5 USD per month per household would recover all service costs at a level of 500 households. Since we only have 143 households currently this model has yet to be fully tested. The user fee covers the servicing and maintenance of the toilets but not the waste treatment. Waste treatment costs will have to be recovered through a combination of compost sales revenue and tipping fees from waste treatment for other sanitation providers. I thought that most of these innovative projects (Sanergy, X-runner etc.) relied on a similar model of mixed revenue from user fees and compost sales. I would be interested to hear how all costs can be covered through user fees and what "all costs" means, ie: does this include organizational overhead and waste treatment?

Household toilet model in IDP camps: SOIL is currently working in IDP camps in Port au Prince and we have not yet tested the household model in these situations. As Kory said it is theoretically possible but we have used larger public toilets to serve a greater number of people with less space requirements. It would be possible to use the household toilet but the financial model would be different as people in IDP camps are not in a position to pay for sanitation.

Compost sales: SOIL has sold over 70,000 gallons of compost to date ( www.oursoil.org/october-2013-newsletter-...-gallons-of-compost/ ), all from our toilets. We have recently started to treat waste from other toilets ( www.oursoil.org/soil-caracol-waste-treatment/ )> This has generated some cost recovery for the composting process but to make it sustainable we will need to increase our paid treatment services and sell more compost. Stay tuned!



Posted by the SOIL Team based in Haiti since 2006. Find more information about SOIL at:
Website: www.oursoil.org
Facebook: www.facebook.com/SOILHaiti
Twitter: @SOILHaiti.
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Sasha Kramer from SOIL here, hi Steve! I just wanted to take a crack at some of your questions:

1 The viability of the collection, composting and reselling process can be troublesome. Transport for collection is usually one of the larger costs components and the more money that can be made from reselling the humanure / vermicompost the better. This is a tough market with low margins, but how are the economics stacking up to date?

Response: The collection and transportation are covered by user fees and not compost sales (the compost sales go towards recovering costs for composting). You are indeed right that transportation is the largest cost driver, especially in Haiti where roads are terrible and there is a frequent need for vehicle maintenance. However we believe that at a break-even point of ~500 toilets we could cover collection and transportation costs from user fees. The composting end is another story. We have yet to see a composting operation that fully recovers costs, generally it is just a more cost-effective way of treating waste when compared to more traditional methods. We predict that compost sales and tipping fees could result i complete cost recovery but we are not there yet.

2 If I was a customer I can see the advantage of a box and taking control over my families excreta management and the privacy and dignity this brings. However, if I was poor and wanted to save money, I would also be tempted to dump the bucket in the local river and avoid the collection service charge. Have you noticed this as problem?

Response: We avoid this problem by renting out the toilets for a monthly service fee rather than selling people the toilets. As long as people are paying the fee they are certainly going to insist that they get the collection service (disincentivizing dumping in ravines) and if they stop paying the monthly rental fee for more than one month the toilet is taken away.

3 Have you thought of Black Solder Fly larva for processing. They love fresh shit and have real value. Also wood ash capture for the nutrient in the urine?

Response: We do use black soldier flies at our composting sites, but we have found that for some reason they don't seem to like our shit, they prefer vegetable wastes. We mostly use them for composting of other organic wastes and then feed the larvae to chickens and ducks. I like the idea of wood ash for capturing nutrients from urine and this is something we may try in the future. For now much of our urine is used to keep the compost piles moist and the rest is soaked away at the toilet sites.

Posted by the SOIL Team based in Haiti since 2006. Find more information about SOIL at:
Website: www.oursoil.org
Facebook: www.facebook.com/SOILHaiti
Twitter: @SOILHaiti.
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  • kcrussel
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Hi Everyone,
I'lll try and fill in some additional responses, though Sasha has pretty much answered most of the questions already. Thank you Sasha!

From Steve Sugden
First off, thank you so much for the positive words.

1 The viability of the collection, composting and reselling process can be troublesome. Transport for collection is usually one of the larger costs components and the more money that can be made from reselling the humanure / vermicompost the better. This is a tough market with low margins, but how are the economics stacking up to date?

The transport is indeed one of the biggest cost drivers. SOIL has explored various creative ways to drive this cost down, including using three-wheeled cargo motorcycles instead of cost- smaller capEX on the vehicle, coupled with a higher utilization rate of the vehicle's capacity, help make the costs more tractable at smaller scale.

2 If I was a customer I can see the advantage of a box and taking control over my families excreta management and the privacy and dignity this brings. However, if I was poor and wanted to save money, I would also be tempted to dump the bucket in the local river and avoid the collection service charge. Have you noticed this as problem?

It has not been a challenge for us at the scale of operations we have observed so far, but we do anticipate that it could become a problem when the service area is larger and it is harder for the service operator to verify that all toilets are being serviced. For this reason, we believe it's important to build monitoring and cartridge tracking tools now that can easily scale with the service. We are exploring paper-based and mobile-based tools.

The mobility of the toilet and the subscription model also help discourage this behavior. Like Sasha said, after a certain grace period, the toilets are removed from users who do not pay the subscription fee.

Of course, if a user no longer has a toilet, then they are likely left with the inadequate sanitation options previously available, which is the same situation they would face if they could not afford to have a pit latrine emptied. This is of course not a desirable outcome, but the fact that payments and expenses associated with this service are regular and predictable can help prevent "defaults" and associated lapses in access to sanitation. Costs for the poorest of the poor are a challenge confronting all market-based solutions, and we continue to seek more ideas to improve access. In the future, we are interested in exploring different incentive programs that could help reduce the cost of the service and increase its accessibility to poorer residents, but those ideas are in their infancy.

3 Have you thought of Black Solder Fly larva for processing. They love fresh shit and have real value. Also wood ash capture for the nutrient in the urine?

We have actually followed your work on BSF with keen interest, because of what we see as a great potential. With the SOIL team in Cap Haitien, we attempted to raise BSF on the shit/peanut shell/bagasse mixture from our toilets in some BioPods in Haiti. While we could get vigorous colonies of BSF on kitchen waste, we had trouble with the fecal mixture. We are very excited at the prospect of higher value ways to extract the resources embodied in waste!

Questions by Elizabeth:
-The mobile toilet costs 75 USD (locally produced). (my question: that's not so cheap? Is there a cost-breakdown available?)

You are correct that the toilets are not as cheap as we would like it, however it is still cheaper than most available designs. The big cost driver is the price of materials in Haiti. Specifically, the model used in the pilot study was coated in Formica which made the toilet easier to clean, somewhat water repellent and much more attractive. However, the Formica was about 50% of the materials cost.

SOIL later phased in monthly payments (still operating today) (would be good to know details of their payment collection scheme; if someone fails to pay, is the toilet taken away again? This is how Sanergy does it.)
(so you already have a secondary revenue stream? But I guess this compost is not solely from these toilets but also from others?).


Sasha answered part of this question but, yes, there is a secondary revenue stream in the Haiti context. Moving forward however, we are interested in finding where the price floor for complete cost recovery (O&M as well as Treatment) with and without secondary revenue streams lies.

Continuing on to answer Sasha’s question: I thought that most of these innovative projects (Sanergy, X-runner etc.) relied on a similar model of mixed revenue from user fees and compost sales. I would be interested to hear how all costs can be covered through user fees and what "all costs" means, ie: does this include organizational overhead and waste treatment?

These other innovative projects are trying to integrate secondary revenue streams. However, I was simply noting that there are user fee price points that could cover all costs. Now whether those user fees are still attainable by the poorest of the poor remains a very open question. This is especially interesting considering these backend product markets can be very tough markets with low margins as Steve pointed out. While we've had good conversations with Sanergy and x-runner about their strategies for cost recovery and profitability, we don't want to speak on their behalf and risk making inaccurate statements. It would be best to have the breakdown of their cost structures directly from them.

All the best
Kory

Kory C. Russel
PhD Candidate
Stanford University
jennadavis.stanford.edu/people/kory-c-russel
www.resourcesanitation.com
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  • CeciliaRodrigues
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Hi Kory, hi everyone!

Thank you all for this very interesting thread. I am learning a lot from it.

@Kory, I watched the video of your presentation at the webinar and there you mentioned that you were considering other treatment technologies and back-end products besides composting, such as the DEWATS and biogas. I am wondering how your research evolved in this regard. Would that be technically feasible considering that you are adopting UDDTs? I suppose you are using sawdust or some other dry material, wouldn't that interfere in other treatment processes?

Kind regards,
Cecília.

Programme Officer at GIZ - Sustainable Sanitation Programme
and the SuSanA Secretariat
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Thank you Kory and Sasha for your comprehensive replies. I think we can proceed in India with a little more confidence in the economics of collection, although disposal still seem to be an issue.

Black Solder Fly - I recently heard from elsewhere that they prefer other forms of organic waste to shit, and who can blame them?

Cost of unit production - seems to be recurrent issue and I wonder if the wooden / concrete versions have the same appeal. We really need to agree on one design and then approach a single supplier and encourage them to invest in a mold. They usually talk in selling 10s of 1000 of units to enable them to recover their mold costs, so even if we got together, it would be a hard sell. Tim at Envirosan in South Africa may be interested and the may even have an existing design which could be used.
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

The issue in India is certainly disposal. We collect from circa 4,000 people daily (and growing) using a communal unit. There is no mature organic market and so the price you can receive for the compost is minimal. We are looking at options for a value added product and are trialling this. We collect both solids and liquids.

We are currently doing the same thing in villages with single chamber UDDTs and a collection service, but it is too early to discuss the sustainability.

As for the units, we currently have an urban (slum) system that doesn't give us the life/cost ratio we want. We are trying to get the price down to $300 with a life cycle of 30 years, and are working on a 'virtual' final design as I write. Our model is self-sustaining over this kind of life-cycle.

We will have more information later this year or early next.
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Hi everyone
i have enjoyed your discussions about this toilet and business around this. I would love to know your experience about the relation between acceptability of this toilet and culture of people or communities where you apply this. Especially in rural India, it seems quite heard to push such toilet as people do not want to see their shit after they leave. There are two key aspects in rural areas which play big role in sanitation behaviors and application of technologies. People who have place in house always want permanent toilet of their won. These people look for two kinds of design (1) septic tank and (2) pit latrine. The pit latrine ( twin pit) are good as it decompose on site and likely to be sustainable mainly for areas where water table is not high and not flooding. it might be similar to many other countries. the other thing that people do not like in India is dry toilet as the culture is using water after defecation. I think toilet in rural areas ( like India) only when majority of people have toilet and do not allow the poor to defecate in their land. In such social pressure poor have no choice other than such toilet.
i see the chances of trying this in India is in urban communities where people do not have space at all in home for constructing toilet, neither they can go out for defecating. i also would love to know your experience in reducing the cost of this toilet if it is made of fiber. In urban areas, the business could be around collection and transportation if it is mechanical in India. It needs to be completely mechanical here in India because the low against manual scavenging.


regards

satya

Senior Program Officer at Water For People -India
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

There are some good points here, perhaps most importantly about scavenging. Early liaison with the local authorities to explain about ecosan is vital.

I would also say that you need to have a model village to which you can show future villagers. Work in clusters that are adjacent to each other and peer groups become your best motivators. Train and educate your first group, build your ecosan, wait a few months and start to take in SHGs and councils. Once they see the difference between a pit toilet (even twin pits) and an ecosan our experience is there is only one winner.
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  • kcrussel
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums (Stanford University, USA)

Hi Everyone and thanks for all the comments and questions.
It is always exciting to see threads that have been dormant still being useful. I’ll try and address each of the questions and comments in the order in which they were posted.

Cecília:
…mentioned that you were considering other treatment technologies and back-end products besides composting, such as the DEWATS and biogas. I am wondering how your research evolved in this regard. Would that be technically feasible considering that you are adopting UDDTs? I suppose you are using sawdust or some other dry material, wouldn't that interfere in other treatment processes?

Yes, you are correct we do not see the household cartridge-based toilet as strictly married to composting and the household toilets are urine diverting (I will use the acronym CBS for Cartridge-Based Sanitation). It really depends on the context in which the service and toilets will be used as to the most appropriate back end processing. In Haiti it made sense to use composting because, SOIL has done such a fantastic job of exploring and creating composting facilities. They have also spent a long time nurturing and investigating the market for finished compost in Haiti. There is evidence that compost markets appear to be rather robust in other locations including Africa and Latin America.

However, in many contexts that may not be the case and it could be far less technically feasible to use composting. In those cases there are other technologies, which are being developed that could be slotted in and replace composting as the treatment methodology. The key is which technology is most appropriate for the situation and how will it impact the service.

1.) Waste Enterprisers in Mombasa, Kenya are doing some very innovative work with fecal sludge where they turn it into biofuel pellets that can be used in industrial processes in Europe. The waste coming from our system would be especially welcomed as it has much lower moisture content.
2.) The Climate Foundation is doing some really cool work with biochar. They are currently testing shipping container sized biochar units with Sanergy in Nairobi Kenya. The waste that Sanergy in collecting is very similar to the waste that SOIL is collecting in Haiti.
3.) Loowatt is doing some very interesting work with biogas and container based toilets in Madagascar. However, they are also using a proprietary bio-plastic film to seal the waste for transport. If you were considering biogas, the cover material choice would be very important and need to be considered carefully. Most Anaerobic digesters need a higher moisture content than what our waste has, and woody substrates tend to be harder to digest. Different digester technologies like high-solids anaerobic digestion could still be interesting. The choice of cover material is also important for composting (in Haiti, SOIL is using sieved sugar cane bagas and crushed peanut shells).
4.) Black Soldier Fly is something that SOIL has looked into in Haiti but as Steve Sugden noted they seem to really prefer other forms of organic waste, which was also true in Haiti. This is not to say that it can’t be done however it will have a much steeper learning curve.

Disposal is a key component but one that several teams are working on. CBS can work with multiple types of back end treatment which increases flexibility. The key is to find the disposal and treatment method that fits the location.

Cost of unit production - seems to be recurrent issue and I wonder if the wooden / concrete versions have the same appeal. We really need to agree on one design and then approach a single supplier and encourage them to invest in a mold. They usually talk in selling 10s of 1000 of units to enable them to recover their mold costs, so even if we got together, it would be a hard sell. Tim at Envirosan in South Africa may be interested and the may even have an existing design which could be used.

I agree that cost of toilet units is key. SOIL has been able to significantly reduce prices with their concrete models. As Steve has noted, there is potentially less aspirational value with locally produced wooden or concrete models. A key hurdle Steve also hit on and that we have encountered with our model specifically is the need to produce 10s of thousands of units to reach economies of scale. I think Envirosan is a great option for manufacturing. However, I would caution against modifying their current designs, as the ones we are familiar with are not well suited for compact, cartridge-based emptying. We fully agree with the idea of getting several organizations on board that are all interested in ordering units to reach the necessary scale. It may not be possible to have one universal design, however, as it could lead to a design that works ok for everyone but not great for anyone. If we could get all the interested parties to come together to express their needs and finalize a design that meets those we could really make some progress. This is an effort that re.source is very interested in leading.

Especially in rural India, it seems quite heard to push such toilet as people do not want to see their shit after they leave.

Satya,
You are completely correct, this model is not designed for rural areas. There are several reasons CBS is a poor fit in rural areas.
1.) Distance and transport costs are much greater.
2.) Demand for sanitation is much lower than in urban areas.
3.) There are much lower cost (or more culturally targeted) options that often make more sense like the Arborloo or the twin-pit pour-flush models.
4.) Space constraints are less of an issue.

Given the availability of such technologies for rural areas, we tend to view the challenge of rural sanitation as a demand creation, behavior change, supply chain, and business model challenge more than a challenge revolving around the toilet interface itself.

i see the chances of trying this in India is in urban communities where people do not have space at all in home for constructing toilet, neither they can go out for defecating. i also would love to know your experience in reducing the cost of this toilet if it is made of fiber. In urban areas, the business could be around collection and transportation if it is mechanical in India. It needs to be completely mechanical here in India because the low against manual scavenging.

As noted above you are correct, urban areas would be the ideal location to attempt this. We have explored toilets built from fiberglass as have x-runner in Peru and Mosan in Bangladesh. Fiberglass is great for low volume runs however; there is very little reduction of costs with scale. Fiberglass toilets are much higher quality than either wooden or concrete toilets and definitely easier to clean.

Finally, you are also correct that the legal situation is especially tricky in India. Other organizations have attempted efforts in India only to be limited in their scope. I think David makes a good point that before trying anything in the CBS or ecosan suite of options, it is best to get the buy-in not only of the community but from government and regulatory officials as well. The idea of having a demonstration community would be especially helpful in getting their buy-in. It is our understanding that Sulabh has some interest in CBS, and they may have the right relationships to be able to start exploring this system in India.

As for the units, we currently have an urban (slum) system that doesn't give us the life/cost ratio we want. We are trying to get the price down to $300 with a life cycle of 30 years, and are working on a 'virtual' final design as I write. Our model is self-sustaining over this kind of life-cycle.

David, thanks for sharing this information. We'd love to hear more about your toilet design, and particularly the constraints you're designing for- squatters and washers, I presume- but other considerations about space, any thoughts about material, waste removal interface, etc.

Thank you all and we of course would love to hear more comments and thoughts.
All the best,
Kory

Kory C. Russel
PhD Candidate
Stanford University
jennadavis.stanford.edu/people/kory-c-russel
www.resourcesanitation.com
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  • stilmans
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  • Environmental Engineer working on anaerobic systems and mobile sanitation; PhD in Env. Eng. on Resource Recovery from Waste
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Re: re.source: Mobile Sanitation Services for Dense Urban Slums

Hi Everyone,

At Elisabeth's suggestion, I wanted to provide a brief update on what we at re.source are working on.

We have some more funding including from the U.S. EPA, and continue to help advise SOIL and others on household container-based sanitation. We initially did more work on our toilet design, aiming for a mass producible design. We have since concluded that between MoSan and xrunner's latest partnership with separett , there is enough effort on this aspect and we are more focused on software, logistics, and the business model.

We also are excited about locally-produced toilets. The models that SOIL continues to develop after our joint pilot are great. The wooden models are vulnerable exposure to moisture and urine, but this can be worked around. In the original units we deployed, we had a liner on the inside from recycled plastic tarp to protect the toilet from urine. SOIL's ferrocement model of course is less prone to this challenge, but is also less portable. Ultimately, we are very excited that SOIL and others groups including Sanivation are diversifying the range of dry toilet models available to users.
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