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How does faecal sludge get taken away and treated in different settings?


Hi -

I am interested to know a bit more about the mechanics of pit emptying for latrines and sludge treatment; particularly in rural settings. One specific thing it would be good to know: in urban areas I understand that companies come and collect the sludge, suck it out, then it can be dried for use as a fertilizer or treated and disposed of. But how are pits emptied in rural areas? Do people just dig another hole when the current one is full? What are the implications of this for the superstructure that sits above ground?

Also, what does LLTS stand for?!

If there are any documents or briefing available on pit latrine emptying and faecal sludge treatment that would be great.


2 Answers


Hi Emily. It's a vast topic. But for rural areas, in the majority of cases, nothing happens: the pit gets full, you dig another pit, move your slab and superstructure (or do another one), and that's it. Emptying a pit is costly and messy so if you don't need to do it, you don't do it. That's why ideally superstructures should be easily movable, in practice it can mean that people build makeshift ones (bamboo/wood + sacks or tin sheets as walls) which can reduce the durability.

In small towns, you do however run into issues when they have a density that precludes digging another pit, but such a small size that an emptying service is not viable. In this case there is no easy answer; in WA we have some initiatives to look at (notably a co-composting plant in Bangladesh for a small town, and some experiments in Madagascar with emptying pumps and drying beds).

In cities you are right, although the vast majority of pits are not safely emptied: they often remain full (cost to empty too prohibitive), get emptied by informal / illegal emptiers (who work at night, use shovels and no protective equipment, and dump everything nearby), get emptied formally but tankers discharge everything in rivers (avoid discharge cost), treatment stations are often designed for sewers and not pit contents and are overloaded... a vast topic! There's a movement now to find solutions but also to analyse and map how cities are doing, hence the "shit-flow diagrams" (an example in my blog on different tools). We have done that for instance in Siem Reap (Cambodia) and several Ethiopian small towns.

For a good starting point can I recommend the technology sheets on our website. And then maybe we could have an internal webinar / course on the topic for people interested...

Finally, LLTS stands for "Leader-Led Total Sanitation", a variant of CLTS developed in and for Burkina Faso by WaterAid. More information in this brief. THere are more recent docs but in French.


Great - thank you Remi! This is really helpful. I have added LLTS to our jargon buster on the Source - that particular acronym wasn't on there!

efyson gravatar imageefyson ( 2017-02-28 14:37:27 )
Elisabeth von Muench

Hi Emily,

You might also find browsing the SuSanA Discussion Forum here useful:

It's certainly a vast topic, like Rémi said.

I have a question, you said:

I have added LLTS to our jargon buster on the Source - that particular acronym wasn't on there!

Is this jargon buster publicly available?We have our own jargon buster here on Wikipedia (list of abbrevations used in sanitation):

I would like to perhaps check which ones I would still need to add. This is something that could be done through our upcoming Wikipedia edit-a-thon where WaterAid is also in the organizing committee (

Regards, Elisabeth


Hi Elisabeth. Our internal jargon buster is on this Google Doc and includes an acronym list and glossary in our four operating languages. As you can see it's a blend of sector words and in-house jargon, so maybe not always useful for external people!

Emily's question was originally on WaterAid's internal KP but was made public.

Rémi Kaupp gravatar imageRémi Kaupp ( 2017-03-09 17:34:50 )