Benefits and economic viability of domestic rooftop rainwater harvesting

The government of Karnataka in the year 2005–06 implemented domestic rooftop rainwater harvesting (DRWH) programme through the Rural Development and Panchyati Raj Department in all the 176 Talukas (sub-divisions) of 27 districts (divisions) of the state. This programme covered one village in each Taluka of the state with at least 20 household level rooftop rainwater harvesting systems. The main objective of the present study was to analyze the benefits of DRWH programme and examine the economic viability of DRWH structures. The study revealed that the DRWH systems were very much beneficial to the sample households in terms of saving time for water fetching and supplying water for different economic activities like pottery, hotel management, kitchen garden, sericulture and silk sarees weaving in the study area. This led to increase in the income of the people and reduction in the production cost. The study on economic viability of investment in DRWH technology revealed that the Net Present Worth (NPW) was positive, B:C ratio more than unity and Internal Rate of Returns (IRR) more than that of referenced bank rate and Pay Back Period (PBP) was very low. These all indicated that the investment in DRWH was financially more feasible and adoption of DRWH technology in the study area was economically attractive.