Every year, more than 2 million people die from water-borne illness. The majority of these are children under 5 years old. These deaths account for 15% of all deaths of children under 5, and are equivalent to one child dying every 15 seconds or 20 jumbo jets crashing every day. These deaths are preventable with access to proper water treatment and hygiene practices. (WHO 2000)
Chlorine is a cheap and safe method to treat water. Programs which have introduced chlorine treatment at the household level have seen significant decreases in rates of water-borne illness (22-84%). (CDC 2005) However these programs have also met some difficulties, including:
- The cost of purchasing bottles of chlorine deters regular use or can lead to users diluting the product.
- Errors in dosing occur, leading to either water that is under-chlorinated, and therefore not fully disinfected, or over-chlorinated to the point that it is unpalatable, discouraging the continued use of chlorine.
There are already many good examples around the world of programs which include both education campaigns and the implementation of systems which recommend the treatment of water using chlorine.
Chlorine disinfects water, killing bacteria and viruses, making the water safe to drink. Unlike other methods, such as boiling, chlorine continues to remain in the water and protect it from re-contamination. This quality is important because often the original water source may not be contaminated but water contamination occurs during transport or storage in the home.
Programs which have introduced chlorine treatment at the household level have seen significant decreases in rates of water-borne illness (22-84%). (CDC 2005) However, these programs have also met some difficulties. Often, the cost of purchasing bottles of chlorine deters regular use of the product or can lead to users diluting the product. In addition, errors in dosing occur, leading to either water that is under-chlorinated, and therefore not fully disinfected, or over-chlorinated to the point that it is unpalatable, discouraging the continued use of chlorine.
In Kenya, the NGO Innovations for Poverty Action (IPA), worked with researchers from Harvard University and University of California Berkeley to attempt to solve these problems by creating a "community chlorine doser." A field trial of 20 devices has returned promising results, as random testing of household drinking water showed increased rates of proper levels of residual chlorine in the drinking water.
Description of the Baseline IPA Community Chlorine Doser[edit | edit source]
The dosers are located near the water collection site; boreholes, wells and unprotected springs. The chlorine is stored in a plastic container which is supported by a metal stand and protected by a metal cover. A plastic valve is attached to the base of the plastic container which releases 3-ml of chlorine with each turn.
The current prototype is clearly functional, yet still contains challenges. Currently, the cost of the device ranges from $60-$90 depending on the location, and a significant portion of this cost can be attributed to the valve which is manufactured in the USA and costs $22.50. Furthermore, it is difficult for the user to know when the chlorine needs to be refilled as the container is completely rigid and must be opaque to protect the chlorine from degradation from sunlight. The system also only accommodates dosing one size of container, while in reality, users often collect water in containers of various volumes ranging roughly from 5 L to 40 L. After an 18-month trial period, many of the metal stands have rusted, some to the point of needing replacement. Construction of the metal stand also necessitates welding, electricity and skilled labor, which may not be available in all locations.