You will need:
- Charcoal- you can collect them from the left over coal from your barbeque, chimney or pieces of burnt wood from your holiday campsite.
- Small pebbles or stone chips - washed.
- Fine grain sand - usually found at the riverbank or your neighbourhood park - washed.
- Shower head.
- Water pump for pumping the water.
- Prefiltration water collection tank.
- One filtration tank with the top open.
- One collection tank.
If you use stream water you can pump the water directly onto the filtration tank, but if you are using ground water that might contain sediments then collect the water in a pre-filtration tank . Wrap some alum in a fine cotton cloth and keep it immersed in the water for at least 5-6 hours. This helps to precipitate the heavy sediments in the water. You will need about 25-300 gms for every 1000 litres of water.
From the collection tank pump the water to the shower. Let the shower water fall over the open top filtration tank. When the shower water falls it gets aerated and this helps in oxidation, helping to remove iron.
In the filtration tank make the filter bed in the following sequence:
- Top layer- charcoal pieces
- Middle layer- small pebbles/chips
- Lower layer- fine grain sand- this traps impurities not trapped by the top layers
Each layer should be about 6 inches thick. As the water seeps through each layer, the impurities get collected in the layers, allowing the clean water to pass through.
At the bottom of the tank, make an outlet for the filtered water to percolate down to the collection tank. This tank collects the filtered water. From there you can tap it off to use for cooking or drinking purposes.
This system is easy to maintain, as it is renewable every three months. Moreover you can reuse the materials like sand and small pebbles for other work like construction. So nothing gets wasted and you get clean water without polluting your environment.