Globalteer volunteers with the Cambodia Clean Water Project recently took part in a “first for Asia” when they helped to install a giant, floating bio-sand water filter on the bank of Tonle Sap lake just outside Siem Reap.
British volunteers Joe McDermott and Adam Felton joined staff at the project on the innovative task which will help supply clean drinking water to the inhabitants of the Tonle Sap’s famous floating villages.
Tonle Sap is the largest lake in Southeast Asia and is home to thousands of people who live in floating houses that rise and fall as the water level changes between dry and monsoon seasons. The challenge for the Clean Water Project was to find a way of installing one of their tried and tested water filtration systems that could withstand the regular flooding that goes hand in hand with the huge ebb and flow of the lake’s waters. Traditional concrete filters frequently become damaged by flooding.
An early start
So, the team set off early one morning in a flatbed truck and then transferred to small boats with outboard motors and headed for the site of the new water filter. The villagers had already constructed a large wooden frame inside which the giant “water filter” – essentially a huge woven bag filled with sand – would be attached. After thoroughly testing the robustness of the wooden structure - by jumping and climbing all over it - the team began the arduous task of filling the bag with sand, the essential filtering agent.
After three long, hot hours of passing buckets of sand along a human chain, the task was complete – the bag now contained TWO TONNES of sand! In addition to the physical filtration that the sand provides, over time a natural “bio-layer” grows which also “eats” away at dangerous pathogens in the water. A pump takes water from the lake and pours it into the top of the water filter and as gravity does its work the water passes down through the bio-layer and then the sand, removing dangerous contaminants and pathogens as it passes through. Clean, filtered water is then drawn off from a tap at the bottom.
An innovative solution
The beauty of this innovative system is that just like the villagers’ homes the filtration bag is buoyant and in the event of flooding it will move up and down with rising and falling water levels, minimising any risk of damage to the potentially life-saving water filter. This new, large-scale buoyant filter will supply clean filtered water to the villagers and is a huge step forward in reducing outbreaks of potentially deadly water-borne diseases and the impact they can have on families and communities.
How to get involved
If you would like to contribute to the amazing work of this fantastic project, you can find out more on our Cambodia Clean Water Project page. We look forward to seeing you in Cambodia!