Assessment of Domestic Rainwater Harvesting Potential in Tropical Monsoonal Climate of South Asia Using Remote Sensing

South Asia is a densely populated land mostly with low income people living in the rural areas. Almost 134 million people in south Asia do not have access to improved water sources. Development of centralized piped network based water supply system is not a feasible option in these rural areas due to economic constrains. This kind of system also requires construction of large impoundment infrastructures on the water body which has enormous environmental and ecological impacts. Domestic rainwater harvesting could be the sustainable and cost effective solution in these rural areas due to its social acceptability, environmental friendliness, lower capital and maintenance cost. Estimating rainfall variability is the key to successful design of rainwater harvesting system. Traditional gauged measurement provides the magnitude of rainfall at a point location and stations are even sparsely located in the developing countries. Plethora of high resolution satellite rainfall data are available that give the spatial coverage of entire world. So rainfall estimation using remote sensing is more appropriate for hydrological applications in developing countries. The objective of this study is to find a hydro-meteorological solution using remote sensing to supply sufficient water throughout the year in rural areas of south Asia. Monthly rainfall variability of each precipitation grid were estimated by analyzing the precipitation climatology from satellite precipitation data. The whole region was classified into smaller areas according to this rainfall variability. Significant portion of the rainfall occurs during the rainy season due to the Indian monsoon. In the end, we developed a framework for storage and usage of this monsoonal precipitation by incorporating quantitative water management concept to maximize the water availability.