Improving Pit Latrine Emptying
Why empty pit latrines?
In developing countries around the world many millions of people have been encouraged to use pit latrines in an attempt to end open defecation, which is a major cause of disease. Ventilated Improved Pit (VIP) latrines are the tool of choice for governments and NGOs (although potentially better options do exist), whilst holes in the ground with a couple of planks on top are often used when poor households are left to build their own latrines.
A problem often not considered is what to do when these latrines become full. In rural areas where cheap structures have been built by the home owner a new latrine can easily be constructed, but in urban areas where space is limited this will not be possible. Additionally, the construction of safe, desireable, permanent structures can be at considerable cost, and so emptying is likely to be a cheaper option.
Why is innovation required?
Using a vacuum tanker to empty pit latrines is a good solution where it is possible. Unfortunately in slums and some rural areas access to pit latrines is almost impossible for these large vehicles. Additionally, they can struggle to empty some drier pit latrine without the addition of a large amount of water and have a high capital cost.
In many places pit latrines are therefore emptied by hand. Although this can be fast, the health of the emptiers is at risk. In places such as Africa, where labour is cheap, it is unlikely that hand emptying can be beaten on price, but after watching the video below you'll be in no doubt of the need for an improved method of emptying: