Hi Wini,
Welcome to the forum! The question about anal cleansing water from UDDTs (urine-diverting dry toilets) comes up with some regularity. I have therefore moved your post into this thread here where we've spoken it before. Please review the posts above this one and see if it's helpful for your case.

If you're working with UDDTs for a Muslim population, then be sure to also read this thread which should give you some pointers:
"Are there some studies that indicate acceptance of ecological sanitation systems in Muslim countries?"
See: forum.susana.org/forum/categories/34-uri...-in-muslim-countries

About treating the anal cleansing water, the general consensus seems to be to use simple sand/gravel filters for it (unless there's an issue with high groundwater table). Did you check if the GIZ Technology Review has relevant information for you on this issue?:
www.susana.org/en/resources/library/details/874

Here are two photos for you from a soak pit for anal cleansing water at a household UDDT in a pilot village in Morocco (by GIZ AGIRE program):

Puits d'infiltration (soak pit for anal cleansing water) by SuSanA Secretariat , on Flickr

Puits d'infiltration (soak pit for anal cleansing water from UDDT) by SuSanA Secretariat , on Flickr

Please tell us more about your work and how you progress?

Regards,
Elisabeth

hello, i am an MSC student at UNESCO-IHE doing my thesis in productive sanitation in emergency case study of south Darfur IDP camps. i am piloting UD latrines and planning to recover dry excreta but i have problem with the anal cleansing water, i want to get red of of it in safe way. so i was thinking of using biological filter beneath the pit using lava rocks, and alluvial sand. however, i will be facing anoxic conditions sine the pit cann't be ventilated. any ideas on weather this could be sufficient or any other ideas.

I would like to comment on the issue of anal cleansing water drains and aquifer contamination; would think, or hope, that these issues are pretty obvious to all those who deal with the relevant ecosan resp. sewage treatment issues.

The UDDts that we construct have the extra bowl for anal cleansing water which gets drained into a mini soak pit of one cubic foot.
Anal cleansing typically being done after defecation, at least the type of anal cleansing that requires more than half a liter of water, the amount of fecally contaminated water that soaks away into the (top)soil is minimal. Without having this checked physically, I would assume that most of these soak pits create a zone of moist soil within a few cm only, maximum one foot. Which to me appears to be pretty safe, in comparison to sewage-holding soak pits that are larger and reach deeper. In coastal villages (living in South East India, close to the Coromandel coast) the topmost aquifers are mostly contaminated anyway, yet often used as drinking water source via hand pumps. In the villages where we built UDDTs the topmost aquifers are several meters below ground level. I admit monsoon conditions do increase the risk of groundwater contamination significantly. Our mini soak pits (for anal cleansing water) are designed in such a way that the drain pipe (for the bum wash water) ends under the surface level of the rubble fill of the soak pit. Owners / users of the UDDTs are encouraged to plant some ornamental flowers in the pit; we have seen canna being used; this is expected to help in decreasing the volume of water soaking away.

I am ready to make our team check on moisture zones around soak pits of anal cleansing water, at least in a few cases where accessibility (physically and socially) is simple.

Rgds, Lucas

I appreciate the responses, I will see if I can obtain additional details.

Thanks,
Dan

I am just wondering if the issue of anal cleansing water is really only a minor issue. The amount of fecal matter in the anal cleansing water could be relatively low for the majority of "normal" situations (i.e. firm stool, no diarrhea, no haemorrhoids ) - compared to conventional wastewater at least - , and the amount of water is also small compared to other wastewater streams?

The eCompendium states (ecompendium.sswm.info/glossary):

Anal Cleansing Water is water used to cleanse oneself after defecating and/or urinating; it is generated by those who use water, rather than dry material, for anal cleansing. The volume of water used per cleaning typically ranges from 0.5 L to 3 L.

Mind you, I am guessing that the volume of anal cleansing water could be quite a bit higher if a "health faucet" / "bidet shower" is used where the water jet has a bit of pressure (see related discussion thread here: forum.susana.org/forum/categories/71-beh...ets-or-bidet-showers )

Dan, could you also go back to the person who asked and find out if he/she has found out more information in the meantime?

Regards,
Elisabeth

Hi all - just commenting on this post to bring it back to attention.

I'd love to hear any thoughts on Dan's question.

Specifically, I'd be interested to hear not only about anal cleansing water and its implications for the environment but also if anyone has any thoughts/experience on managing this water in densely populated areas (e.g. informal urban settlements).

Hello, I received more details on this information request that I hope will be helpful. Please let me know if you have any relevant info:

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Is there any academic research that has been conducted that looks at levels of fecal contamination of surrounding environment due to anal cleansing.

Obviously if this is connected with open defecation then the point is moot because its all contaminating the environment but if you where to contain the feces but then anal cleanse into a drain that then went out to the surrounding environment is that still as bad from a contamination point of view as open defecation?

I think this could be an issue if you had a dry toilet in a washing culture and then the washing went to a drain and into the environment.

I’m trying to get a sense if containing feces but not containing anal cleansing could be considered a step up the sanitation ladder or not and if there is an research to back that up.

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Many thanks,
Dan

I guess for anal cleansing water going into a soakaway the same limitations apply as for 1) a soakaway after septic; 2) pit latrine; 3) soakaway pit of pour flush : don't do it where GW is easily contaminated i.e. because GW being high or because of underground geology (fissured rock). Impermeable clay may also be prohibitive.

Alternatives?: maybe small constructed wetland beside washroom, which can then take greywater from kitchen, bathroom, laundry, and anal cleansing water. Effluent can be used for garden watering. Other solutions invited?!

ciao, hajo

Have you looked for these specific UDDT squating pans that have a second bowl behind for anal cleansing? As far as I know these are usually connected to a soak pit, and I am sure someone must have thought about potential water contamination from these.

Hello

I received the info request below and have not had any success in finding an answer. Please let me know if you have any studies, etc that would be useful.

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Information Request - I was hoping for something public health academic that looked at anal cleansing water contamination. For example just say you could defecate in a container but then you cleansed into a drain that went into the environment.

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Many thanks,
Dan