Blog

If you are new to Blood:Water Mission and to our work in Africa, we want to enlighten you on the incredibly simple, but effective technology of the biosand water filter. Biosand water filters are an in-home water filtration system that utilizes ancient technologies to purify unsafe drinking water.

The filter, which is roughly the size of a 25 gallon trash can, is assembled to mimic the layers of soil. You see, rainwater is filtered as it passes through layers of soil on its way to the water table (deep below the surface). The biosand water filter is assembled with layers of sand and rock to duplicate this process on a smaller scale.

"But what is the "bio" in biosand water filter?" You may be asking yourself this. Well, for this, image yourself looking at a pond. If it is a pond with some age and without drainage, it most likely has a rather foul smelling, green scum on top of the surface. This is a bio-layer. A layer that consists of many organisms fight and feed off of each other for survival. These organisms like us, need fuel to survive and the pond serves as a feasting ground - good bacteria eating bad bacteria! (And you thought it was just scum).

Each biosand water filter has its own bio-layer on the top of each filter. As dirty water is fed into the filter, it first passes through the bio-layer, where 'good' organisms eat 'bad' organisms! Just like the pond scum! The water then continues down through the sand and rock in the filter to remove the rest of the sediment and pathogens in the water - resulting in safe drinking water!

To learn more about biosand water filters you can consult this fantastically silly, but informative video on YouTube: