Since being first established over 20 years ago, the Aquabox has been very effective in delivering clean water in emergencies. However, its previous use of chemical tablets with a carbon filter meant that it could only deliver a finite amount to cover the most basic drinking water needs of a family for first four months in the case of the then Standard Aquabox or 33,000 litres in the case of Aqua30s. (Both no longer produced: see What We Do pages)
The volunteer engineers at Aquabox were keen to find a longer lasting solution, and a system based on membrane technology seemed to be the answer. Membrane technology is well known and used in public water supply, and a number of versions have been produced for small scale use in developing countries. None of these, though, were found to be suitable, in price, performance, or ease of use.
As a result, a Rotary supported organisation, The Safe Water Trust, was set up to develop solutions which were tailored to the real needs of Aquabox users. Aquabox, led by David Haspel and Mike Tomlinson, worked closely with The Safe Water Trust to help develop the AquaFilter family of products to give a cost effective and highly efficient replacement for our long standing, but limited, chemical based solution.
Research in the field identified two requirements; a water supply for schools, clinics, and other organised communities; and a water supply for family groups of about five individuals.
Typically for those affected by disaster or facing some other emergency situation, water for washing and drinking is collected from any local source, and stored in a container in the family house or shelter. Such water is often contaminated, and so is unsafe to drink.
The AquaFilter Familyunit is fastened to the container, such as the Aquabox or a bucket, and delivers drinking water directly into the user's cup. The filter delivers up to 1 litre a minute, so the user has only to pump to get water on demand. Aquabox has had units on field test now for over three years in African and Asian countries, and these show that that the AquaFilter unit is capable of delivering at least 18,000 litres; enough for 22.5 litres/day of general use potable water for use by the family group for a period at least eighteen months (and often longer).
A washable gauze pre filter, first removes the larger particles, before the membrane removes the smaller biological contaminants. The membrane is continually washed by an internal cross-flow system.
Periodic maintenance includes greasing the pump seal, for which a suitable grease store is built in; replacing the pump seal, for which spare seals are already attached to the piston rod; and chemical washing, for which a pot of tablets is attached.
The unit fits into an Aquabox Gold together with the nearly 70 other items of humanitarian aid. The box itself is made from a strong and robust plastic, and itself becomes a valued resource for dry storage and other flexible uses when once deployed in the field to desperate families, groups and communities.
The AquaFilter Community was developed for schools, clinics and other community amenities, and fits into an Aquabox. This makes for easy storage and transport as part of an Aquabox consignment.
It operates by a hand pump, and delivers up to 300 litres of drinking water an hour (when used by a relay of pumpers!). It has a washable gauze pre filter to remove solid particles. Membrane washing is done by reverse flushing. Periodic maintenance includes greasing the piston seal with grease supplies from a built in container, seal replacement by a new seals stored on the piston rod, and chemical washing with tablets stored on the unit. Preliminary results show a life in excess of 560,000 litres and over eighteen months (and often longer).
Note: AquaFilter Family and AquaFilter Community units remove biological contaminants, commonly found in water from ponds, streams, or shallow wells. They do not remove dissolved substances such as salt, or arsenic, typically occurring in deep wells.
The Safe Water Trust is supported by Cleadon and District Rotary Club (district 1030), and is a Company by Guarantee. It is a continuation of the good work done by The District 1030 Aqua Filter Trust, which pioneered membrane filters for Developing countries.
Visit the Aquafilter website - www.aquafilter.org.uk