Friday, 18 October 2013

Fake poo testing the pour flush

How do you know if a flushing system will work or not? You test it with poo of course!

Well that's not such a pleasant experience so we decided to make some fake poo. The Environmental Protection Agency of America say to use the Maximum Performance (MaP) Testing Toilet Fixture Performance Testing Protocol. Basically this involves getting some soya paste (not so easy in Uganda), extruding a 10cm x 2.5cm cylinder of it and covering it with a condom. The only soya paste we could find was pretty runny (not a healthy poo) so we mixed it with some kaolin clay to make a firmer stool and popped it in some condoms - not sure why George insisted they needed to be black and ribbed though.

You then pop these in to the pan and U-bend you're testing. Chuck 2 litres of water down it and see if the little darlings pop out the other end.

We found a pan and ceramic U-bend that works well with 2 litres of water available on the Ugandan market.

We're currently adapting's chamber box from their easy latrine to take this pan.

Richard will then work with entrepreneurs to sell standardised flushing systems to households and masons. This will also form an integral part of the Dura-San modular latrine so households can have the option of employing a mason to build a brick structure or a Dura-San structure.

The entire structure will look something like this.

The Dura-San

One of the main challenges that has been identified for households to purchase latrines is in the trust between the household and the mason constructing it. Often a householder will go out of their way to buy materials for the mason and only pay him for labour because they don't trust that the mason will be honest in what he purchases. Furthermore, many of the materials available on the Ugandan market are inconsistent so a mason may not be able to buy something as good as expected by the householder.

An answer to this is to produce a standard construction kit; which we've dubbed the Dura-San. Water For People worked with John Parry's Associates to produce mortar less block construction system and then refined the idea in Uganda. We first worked with a large materials manufacturing company called Multiple Industries but found more success with a medium sized enterprise called Turn Key. Concrete manufacturers are quite common in Uganda but ensuring that they produce quality products could be a challenge.

The idea is reasonably simple. Concrete blocks are cast and left to cure.

Once the blocks are cured they're put together by slotting plugs between the holes at the end of the blocks.

Finally a door frame is added at the front and a concrete roof.

It is still a work in progress and requires for a modular pour flush system be produced but, as opposed to our feelings, must people don't think it's ugly and we've had a lot of interest following the trade fair.

The basic idea will be for a concrete manufacturer to be the producer and installer of the latrine, therefore cutting out the need for highly skilled masons and the increasing the trust between the householder and the latrine supplier.