Tigers in the toilet

A tiger worm

Could the Tiger Toilet be a long lasting sanitation solution for refugee camps? We think it could be.

Sanitation is a huge priority for Oxfam as we seek cost effective, appropriate and durable solutions for the many different contexts we operate in – humanitarian camps, following natural disaster and conflict, rural and urban environments.

Earthworm, can digest the contents of the toilet helping them to last longerFor many people across the world, their toilet is a simple covered hole dug into the ground. Whilst these can normally be moved and rebuilt cheaply when they fill up, in areas lacking space or with rocky ground this can become a real problem. In emergency situations people are often displaced into crowded camps, where regular emptying of communal latrines on a large scale is a challenge for humanitarian agencies like Oxfam and the local authorities responsible for it, as
well as the people using the latrines. Desludging is a costly and logistically difficult exercise – tankers may not be able to access the limited space around the latrines, and finding an appropriate disposal site can be tricky – it’s often an afterthought, when it should be considered at the toilet design stage.

We believe we have a solution. Several types of earthworm, of which tiger worms (Eisenia fetida) are just one, can digest the contents of the toilet; reducing the volume of waste inside and helping the toilets to last longer. In fact, the toilets Oxfam built in Liberia in 2013 are yet to need emptying. What’s more, the worms turn the waste into vermicompost – a fantastic fertilizer. If you have a compost heap at home, you’ll know what I mean.

Since Oxfam’s first Tiger Toilet pilot was introduced in Ethiopia in 2013, we’ve learned a few lessons:

  •  It’s important to have good drainage to make sure the worms aren’t flooded out (they need water, but not too much…)
  •  Using multiple layers of material for filtration of the effluent isn’t always necessary, it’s fine to soak into the earth provided it’s not near a drinking water source
There have also been huge successes in other countries: in Liberia, Oxfam is still building Tiger Toilets and has inspired others to build them too  including Oxfam colleagues in Sierra Leone. Oxfam has partnered with others, such as PriMove in India, who have constructed more than 1,200 Tiger Toilets and are still building. Meanwhile, at Loughborough University, Dr Claire Furlong is continuing research into worm-based sanitation systems and results so far have shown that a typical Tiger Toilet might last five years without needing to be emptied.

Now we’re rolling out Tiger Toilets further in Ethiopia and Myanmar. In Gambella, western Ethiopia, we will be building toilets in a refugee camp for South Sudanese refugees, funded by the Bill & Melinda Gates Foundation in partnership with UNHCR. The refugee camps are likely to be in place for a long time (it is now estimated that refugees live within camps for up to 17 years – so sustainable sanitation is crucial!), and Tiger Toilets could be the long term solution required.

This partnership will also include the construction of urine diversion latrines in Gambella. This brief intends to communicate the different and appropriate sanitation models for a refugee context that leads to sustainable, and durable solutions, and a valued waste by products from the sanitation technology (i.e. vermicompost from tiger toilets, and composted waste from urine diversion). In Myanmar the Humanitarian Innovation Fund are backing us to construct them in camps where currently the tanks behind the toilets need to be emptied on a regular basis.

I’ll keep posting as the project progresses.

Angus McBride
Public Health Engineering Team Leader


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