Hi Everyone, Sebastien from re.source chiming in. I think the term "bucket toilet" is loaded both from the perspective of user perceptions and from the JMP definition, as evidenced by the lengthy discussion in this thread.

I think it is important for us service providers to get at the roots of user perceptions of why one toilet system is inferior to another, and to design and operate accordingly. A well-designed UDDT with effective service can be odor-free and pleasant. A poorly-serviced flush toilet can be a nightmare, and I think it is dangerous to assume that user perceptions are universal across contexts and histories.

Instead, we should be marketing sanitation systems the way we do other products and services- by demonstrating how a particular solution fulfills user's aspirations, needs, and desires. If we do this while providing solutions that are technically effective (no flies, no odors, and effective management of the waste), I think we will find that users are not as fixated on flush toilets as we often assume.

Hi! I'm Jessica from x-runner in Lima (Partner with Rotaria - Christoph). We are running a still small UDDT linked with service enterprise in Lima. We have found that our clients are very much aware of the water scarcity and water price in Lima. All of our clients are familiar with water toilets and still the majority prefers the waterless options - and yes, they pay for it. I think that increasing water prices and increasing water scarcity can change perception - in parts of Lima, this is clearly already happening. I am positive that such changes will over time happen in more cities around the world.

we should use the time different than this discussion.
First I thought it is about confusion. I do realize that it is about "beeing right".

Christoph

It seems to me that the simplest solution is to describe interventions by what they are - eg a urine diversion toilet leading into a sealed vault or a dry toilet to a pit latrine.

Does it matter? It seems to me there are more advantages to having urine diversion than not, and more advantages to having a closed vault than pit, so having a urine diversion vault system is probably better than all the other options. Even so, without secondary treatment, none of them are likely to produce sanitised sludge..

Dear Joe,

I think you got me!
That section of the technology review we actually discussed over and over again, and I was somehow never totally satisfied with it.
It is indeed confusing to write:
"As the shallow pit UDDT and its various derivations are not well documented, it is not described further in this publication"
...when earlier I pointed out that UDDTs do not use pits. Will need to consult with the other two authors (Christian and Heike) on how to possibly improve the clarity here, perhaps with an explanatory footnote.

By the way, when I started work at GIZ in 2008, I took over a whole pile of nice documents (thanks to Florian amongst others!). At that time, I "standardised" the abbreviation UDDT to mean: urine diversion dehydration toilet.

When we were writing the technology review, we struggled with that term and in the end Christian convinced me to change my mind. From about 2012 onwards, we started to define UDDT as urine-diverting dry toilet.
We had a debate here on the forum about it in early 2012 which explains the reasons behind this subtle shift for the second D:
forum.susana.org/forum/categories/34-uri...eview-of-uddtsq#1255

I reckon all of the practitioners out there are laughing about us "academic" people right now who are arguing about the meaning of the second D...

But I agree with Joe (and Florian) that this mess of terminology is annoying. We can all do our bit to be very clear on terms in our publications and to help newcomers in understanding what we are on about more quickly.

Elisabeth

The Durban UD toilets have sealed vaults. We'll have to put the word out that they should not be referred to as twin pit UD toilets, to put an end to the confusion.

OK, I was only trying to understand, Florian. I'm saying there is a wide misunderstanding and muddling of terms, and the new report seems to be proving that.

Look, there is no authoritity exisiting that prescribes what should be called how. If you like to call something VIP-UDDT, you are completely free to do so. All I try to tell you, is that if you say VIP-UDDT or UDDT-VIP, most people would not really understand what you are talking about.

Florian wrote: I have to say that I really learned something new through
The DT in UDDT is for dry toilet or dehydration toilet, which is commonly understood (as Elisabeth pointed) out as a lined chamber or another container designed to for collection, drying and easy removal of fecal mater. This is clearly different from a pit, which is basically designed to collect fecal matter without the intention and easy option to remove it from there.
So I'd consider UDDT-VIP not as a correct term, because it mixes two clearly different concepts.

I think that the report disagrees with both of you on this point.

The whole of section 2.6.4 reads (edit: in the technology review on UDDTs, see here:
www.susana.org/lang-en/library?view=ccbktypeitem&type=2&id=874):

In areas with low water table and with minimal threat of flooding, UDDTs can also be constructed with shallow ventilated pits for faeces collection. Often referred to as Urine-diverting ventilated improved pit (UD-VIP), the configuration presents the simplest form of UDDT systems.

Urine is diverted at the user interface and the faeces are dropped directly into the pit where they undergo a natural mineralisation and composting process.

Diverting urine away from the faeces pit offers a number of advantages over conventional pit latrines. Urine separation reduces odours, provides the opportunity for using urine as fertiliser, slows down the filling rate of the pit and may also reduce the risk of contaminating groundwater resources by minimising the generation of pathogen contaminated leachate.

When the pit becomes full, the super-structure is razed or moved above a new pit. Following the examples of the Arborloo toilet (Morgan, 2004) and the EcoLet in Peru (Hoffmann, 2012), a tree may be planted on top of the decommissioned pit to allow the excreta’s nutrient content to be utilised and the toilet’s former location to be clearly demarcated. As the faeces are left in the ground permanently, it eliminates the need for handling. This model of operation, however, is limited to situations where adequate land is available for digging new pits regularly.

Alternatively, the pit can be emptied after one to two years of continuous composting, in accordance with the Fossa Alterna system described by Morgan (2004) and Tilley et al. (2008). The faecal pathogen content is reduced during the composting process.
As the shallow pit UDDT and its various derivations are not well documented, it is not described further in this publication.

The last paragraph (that I highlighted above) suggests that the document is not distinguishing between UD and UDDT in the way you are suggesting, Florian.

Either the report (Technology review of UDDTs) is wrong, or you and Elisabeth are using terms in a different way to the authors of this section of the report.

Thanks, Florian, I had not heard that the second D in UDDT was for dehydration, but rather understood it to be a Urine Diversion Dry (as in 'dry rather than flush') Toilet. Which appears to be how the Akvo/Ewag definitions are using the words. I understood the things I was reading by that definition.

I'd like to suggest that someone coin a term for a UDDT (vault) system which does not use words which can be misunderstood or which can be used to describe another system.

I still think that they're being used in different ways.

I have to say that I really learned something new through this discussion. I was not aware that there are actually examples of pit latrines with urine diversion. I assume that these are not very widespread (the Technology Review says "not well documented").

For Terminology, I'd say UD-VIP would be correct, a VIP latrine with urine diversion.

The DT in UDDT is for dry toilet or dehydration toilet, which is commonly understood (as Elisabeth pointed) out as a lined chamber or another container designed to for collection, drying and easy removal of fecal mater. This is clearly different from a pit, which is basically designed to collect fecal matter without the intention and easy option to remove it from there.
So I'd consider UDDT-VIP not as a correct term, because it mixes two clearly different concepts.

So to summarize, we are talking about 3 technologies here:
- VIP, by far the most widespread toilet type of the three, I think still clearly the most common choice in on-site sanitation
- UDDT, one of the most popular alternatives to VIP or other pit latrines, but still with rather modest distribution globaly
- UD-VIP, a rather exotic solution.

I'm sorry to go back to kicking this subject.

Is not system 3 in christoph's post (from page 11 of the report) a 'pit' as described by Elisabeth previously - in that it does not seem to have an impermeable base or vault, which seems to me to be the crux of the difference you are saying is widely accepted between 'pit latrines' and 'UDDT vaults'?

Section 2.6.4 specifically talks of "Urine-diverting ventilated improved pit (UD-VIP)".
(edit: see document here: www.susana.org/lang-en/library?view=ccbktypeitem&type=2&id=874)

Please help me out, am I wrong or not? Is this the same as the UDDT-VIP I referred to before, or is a UDDT different to a UD?

As I said before, I think this is about how you are defining 'toilet'. Elisabeth seems to be suggesting that a Urine Diversion Dry Toilet is the whole system, whereas others are saying that the toilet is the collection mechanism for the system.