Low-cost tanks and filters in Sri Lanka

Due to the tremendous growth in population and financial constraints, providing a safe and adequate drinking water supply to all inhabitants is the major challenge for a country like Sri Lanka. Bearing this in mind an Asian Development Bank assisted water supply and sanitation sector project is being implemented in Sri Lanka with the adoption of appropriate low cost techniques to minimize the capital cost in rural water supply schemes. The idea of this is to use the available funds to continually increase the served population. There are number of low cost components used in water supply schemes under this project such as ground tanks, elevated tanks, up flow roughing filters, slow sand filters using Ferrocement techniques and submerged, floating filters using prefabricated plastic containers. These techniques are not only suitable for rural water supply schemes, but also in town water supply schemes too. This paper describes the low cost techniques used in number of pipe-borne water supply schemes under this project and it compares the cost with conventional methods.