RESEARCH ARTICLE Planning rainwater conservation measures using geospatial and multi-criteria decision making tools Laishram Kanta Singh 1 & Madan Kumar Jha 1 & V. M. Chowdary 2 Received: 11 October 2019 /Accepted: 20 July 2020 # Springer-Verlag GmbH Germany, part of Springer Nature 2020 Abstract The assessment of rainwater-harvesting demand (RWHD) map and the identification of appropriate priority-based locations for rainwater-harvesting (RWH) and groundwater recharge structures are very crucial for the water managers, particularly in irrigation commands. This study addresses this challenge by using multi-criteria decision-making (MCDM) and geospatial techniques to present a novel and robust approach for generating RWHD map and identifying sites/zones for distinct RWH and groundwater recharge on a priority basis. Primary thematic layers such as existing irrigation water supply, irrigation demand, and groundwater potential were considered in this study for delineating RWHD zones. Further, sites suitable for RWH and groundwater recharge were identified using soil, slope, drainage network, and lineament thematic layers of the study area and they were prioritized. Four zones of rainwater demand were identified for the prioritization of RWH and groundwater structures: (a) “low” rainwater-harvesting demand zone (covering 3% of the total study area), (b) “moderate” rainwater-harvesting demand zone (40%), (c) “high” rainwater-harvesting demand zone (42%), and (d) “very high” rainwater-harvesting demand zone (15%). Moreover, 46 sites for check dams and 145 suitable sites for percolation tanks were identified, together with 253 ha area for groundwater recharge based on the priority of rainwater-harvesting demand. Integration of geospatial and MCDM techniques in conjunction with suitable thematic layers provides a helpful and realistic tool for large-scale planning and management of rainwater conservation measures. Keywords Rainwater conservation . Geospatial techniques . Multi-criteria decision making (MCDM) . Boolean logic . Site prioritization Introduction Individual awareness on the water resources, variations in the water consumption rates, and per capita availability rates coupled with lifestyle changes are some of the key issues in water resources management (WWAP 2009). Increased global population growth rate, particularly in developing na- tions (UNFPA 2008) affected the per capita water availability, which poses a serious challenge for water resources manage- ment. Currently, approximately 3.6 billion population live in water scarcity regions (about one half of the worldwide pop- ulation), which is further projected to rise to 4.8–5.7 billion by the year 2050 (WWAP 2018). Further, wet are areas becom- ing wetter and dry regions are becoming even drier worldwide due to climate change. Currently, 75% of the water is used in the agricultural sector globally, while extra 5600 km 3 year −1 of water will be needed by the year 2050 to meet future food requirements (Falkenmark and Rockström 2006; Falkenmark 2007). Introduction of high-yielding varieties to enhance food production under green revolution initiatives taken up in India during 1967–1977 resulted in the over-exploitation of ground- water beyond a naturally replenishable limit. India is the world’s largest groundwater user that uses estimated ground- water of 230 km 3 year −1 , i.e., more than a quarter of the global total. In India, groundwater serves more than 60% of the Responsible editor: Philippe Garrigues * Laishram Kanta Singh kanta_lai@yahoo.co.in Madan Kumar Jha madan@agfe.iitkgp.ac.in V. M. Chowdary chowdary_isro@yahoo.com 1 AgFE Department, Indian Institute of Technology Kharagpur, Kharagpur, West Bengal 721302, India 2 Regional Remote Sensing Centre-North, NRSC, Delhi 110049, India Environmental Science and Pollution Research https://doi.org/10.1007/s11356-020-10227-y