Use this household filter to help make water safe to drink:
- Clean a watertight 200-litre container and disinfect it with bleaching powder. Make sure the container did not contain toxic materials.
- Drill a hole a quarter of the way down from the top of the container for a tap. The hole should be the same size as the fitting on the tap.
- Fit the tap to the hole and fix it in place.
- Drill or punch many small holes in the first 35cm of a piece of flexible piping, seal the end and form it into a ring on the bottom of the container, with the holes facing downwards.
- Connect the top of the pipe (the end with no holes) to the tap. Seal the fitting with a hose clamp or wire.
- Place a layer of washed gravel 7cm deep on the bottom of the container over the pipe. Be careful not to crush the pipe. Cover the gravel with a fine cloth and fill the container with washed, coarse sand to about 10cm below the tap. Cover the sand with a second fine cloth.
- Make a cover for the container, with a hole in it to pour water through. Cover the hole when not in use to stop insects entering the filter. Place a flat stone or dish under the hole to avoid disturbing the sand when water is poured in.
- Before adding water to the filter, allow any particles in the water to settle. Flush the filter with water before first use.