Chapter 3: Rain Water Harvesting in Developing Countries Check Access

With the worldwide demand for safe drinking water and the continuing dearth in its availability, especially in developing countries, methods to conserve water are the need of the hour. Rain water harvesting (RWH) is one of the many water conservation techniques that is known to humans and has been practised for several centuries. In this chapter, RWH is described in detail. The basic design of the RWH system and its various components are elaborated with emphasis on the calculations to determine the harvested rain water supply based on the catchment area, amount of rain water to be diverted as first flush, length of the downpipe etc. The quality of the harvested rain water is of paramount importance and the nature of the contaminants will determine the type of treatment required to render it potable. The highlight of the chapter is the discussion on the myriad treatment methods available such as chemical disinfection, UV, filtration and solar disinfection (SODIS). These techniques are described in depth and recent scientific work from the literature is included. Merits and demerits of RWH, its typical cost and recommendations for future work are also stated to enable further investigations.