A design plan for rooftop rainwater harvesting in a large defence establishment in central India

Water scarcity in India is impending with the gap between population rise and water demand widening at an alarming rate. Prompt action is imperative to mitigate the malady and make the country liveable. Rooftop rainwater harvesting is an option that can arrest India's declining trend of groundwater levels if implemented in mega-scale countrywide. There are innumerable feasible structures with large roof areas that could be used to harness rainwater. Large building complexes, such as those of ordnance factories, industrial buildings, military barracks, etc., are the ideal sites where huge bulk of water can be injected underground through rooftop rainwater harvesting. An attempt has been made in this contribution to propose a design plan for rooftop rainwater harvesting at the Gun Carriage Factory, Jabalpur, India, that has a large network of connected buildings. About half of these buildings numbering about 16 with a roof area of 60,062 m 2 were examined from feasibility perspective. These buildings together can harness about 59,671 m 3 of rainwater at a rate of about one m 3 of water for one m 2 of roof area. Calculations with design plans were made for each of these buildings. It was advisable for some of the buildings to have combined harvesting systems due to their locational proximity. Similar approach could be adopted in the innumerable pucca buildings across India in massive scale to at least partially eradicate the impending water crisis the country is likely to face in the years to come.