Addressing the sustainability of small-user rural water treatment systems in South Africa

A crucial consideration when considering water treatment in rural communities is the sustainability thereof. This paper compares the financial and technological sustainability of a membrane based water treatment plant versus a conventional type plant at two small rural communities in South Africa, and brief observation is made as to the importance of socio-political sustainability. The membrane-based process is shown to provide consistently good water, whilst the conventional process only provides intermittently good water. The membrane-based plant was successfully operated for an extended period by a community member with no prior skills in water treatment, and showed superior technological sustainability. Using a Net Present Value based approach, financial comparison shows that contrary to conventional wisdom in South Africa, the membrane-based plant has superior financial sustainability. The principle advantage of the membrane based treatment process is that it provides consistently high quality drinking-water and it is not possible for the system to pass on partially treated water that fails bacteriological standards. This will ensure the socio-political sustainability of the membrane-based process. In comparison the regular failure of the conventional system is likely to lead to eventual rejection of the technology by the community.