The equipment that you need
- A wooden crate or similar support (to place the sand filter on)
- The top of a plastic bottle with lid
- A pen/marker
- A 20 litre jerry can that has not been used for kerosene or petroleum products
- Two clean buckets
- About 20kg of sand
- About 3-5kg of pebbles/small stones/ gravel
- A drill or other means to make the hole in the jerry can (see step 2 below)
- Cotton cloth
- One plastic bottle
- One clear plastic or glass bottle
- A stick
- Plastic funnel
How to build the filter
- Mark out eight equally spaced lines on your jerry can (each a section)
- Insert a hole in the front bottom edge of the can (see the picture above)
- Insert the cut off top of the plastic bottle into the hole
- Find some pebbles/small stones/gravel (6-10mm wide) then wash them thoroughly
- Find sand, preferably from a quarry rather than a river bed. If the sand is from a river bed then try to use sand that is further up the bank
- Fill the jerry can in the following ratios: Gravel – 1 section; Sand: 6 sections, Air: 1 section
Maintaining the filter: do this once a month
- Put the lid on the top of the jerry can
- Turn the jerry can upside down
- Take the bottle neck out
- Take the lid off the top of the jerry can and quickly put cloth over the hole to prevent the filter materials falling out
- Pour in one litre of previously filtered water
- Throw away the water once it has passed through the filter
- Remove the cloth cover and quickly put the lid back on the jerry can, reinsert the bottle neck and turn the filter the right way up
- Continue using as normal for another month