Water Filters in Western Kenya: The Next Public Health Disaster?
By Fiorenzo Conte
Imagine that you are a farmer in rural Western Kenya. In the last few years you have been told that the most effective way to have safe drinking water is to disinfect it with chlorine. The biggest advantage that this method offers is that once you treat water with chlorine you do not have to worry about re-contamination for a while: chlorinated water provides ongoing protection for 24 hours. There is a problem though: you need to purchase the chlorine every month so that you can regularly treat your water. The price is very low, yet you have already too many things to worry about and to remember to purchase regularly chlorine sounds to you as another burden. So what do you do? You do not buy chlorine and you continue to live as you did in the past. No big deal.
After a while, the same people come back and install a chlorine dispenser device at the communal water source where you normally fetch your water. This method offers two additional advantages: a community member will be in charge of refilling the chlorine tank once per month so you do not have to worry about regularly buying the chlorine. Additionally, you do not have to worry about the dosage either: you turn the valve of the dispenser and your water is disinfected for 24 hours.
Now, another group of people come to you and offer you what they claim to be THE most effective method to disinfect the water you drink. It is a water filter that is installed for free in your house. They explain to you that this filter eliminates the risk of re-contaminating the water during collection, transport and use at home, because the filter is installed at the point where you are going to drink the water. Hence, forget about the chlorine because your water is safe after you treat it with the filter. What are you going to do? Given that they are coming to install the water filter directly in your home, you will probably stop using chlorine and think that your water will be safe once you treat it with the filter. However, there is something they omitted to tell you: the filter does not prevent water from being contaminated if you touch it with dirty hands or you store it in a dirty container . And storage, together with collection, is the main source of water contamination. Furthermore, you will have to substitute the filter in 3 years and this is going to cost you around a quarter of your annual income, if you are going to buy it.
This tale presents, in a nutshell, what is going on in Western Kenya where Life Straw is distributing 1 million water filters for free, thus undermining the effort to increase the uptake of what most experts in the sector consider to be the most effective water management system i.e. chlorination of drinking water. Such big scale intervention is hard to justify as little (or better, no) evidence exists that people are actually going to use this filter (uptake might be high if you hand these things out for free, but the real issue is if these things are used over time) and no evidence exist that these things are cost-effective ( whole-sale cost + distribution + marketing = $50 !!! They are distributed for free now, but is Life Straw going to replicate a 1million filter give-away every three years? ). Approaches based on chlorination presents challenges (low uptake) yet they have the potential to be scaled up and the cost would be of $0,30 per person per year. It is difficult to understand why local health authorities are encouraging the distribution of these water filters thus setting the stage for what somebody has defined the largest public health failure ever in Western Kenya.