[A-HW24] Human- and Climate-induced variability in water cycle and (sub)surface water resources

[AHW24-P04] A GIS-Based Holistic Approach for Stormwater Harvesting Site Suitability

*SHRAY PATHAK¹, Shreya Sharma², Abdul Gani³ (1.Department of Civil Engineering, Indian Institute of Technology Ropar, Rupnagar, Punjab, India, 2.R&D and Corporate Manager, TIF-AWaDH, Indian Institute of Technology Ropar, Rupnagar, Punjab, India, 3.Department of Civil Engineering, Netaji Subhas University of Technology, New Delhi, India)

Keywords:Hydrological Modelling, Stormwater Harvesting, Site Suitability, Climate Resilience , Multi-Criteria Decision Analysis (MCDA)

With growing water shortages and the impacts of global climate change, adopting sustainable strategies to safeguard natural water sources is essential. Among various water conservation techniques, stormwater harvesting (SWH) is considered the most sustainable method to alleviate the stress from the available freshwater resources. However, assessing stormwater potential and identifying optimal SWH locations using multi-criteria approach presents significant challenges. Therefore, this study introduces a robust method to assess SWH potential and identify appropriate sites, considering suitable selection criteria. A geographic information system (GIS)-based approach screens and identifies areas with high SWH potential, followed by an in-depth analysis. Multiple suitability criteria, informed by expert input, directs the assessment process to support decision-making. The initial phase involves shortlisting potential sites and pinpointing suitable locations within sub-catchments. Consistent spatial-scale thematic layers are created and used as input data for the model. The GIS environment facilitates computations using the distributed curve number method to estimate the spatial distribution of event-based runoffs. Once the thematic layers are established, the Analytical Hierarchy Process (AHP) assigns relative importance to each layer, producing a suitability map for SWH for Haridwar, Uttarakhand, India. This assessment integrates multiple factors to determine optimal locations for SWH structures, ensuring efficient resource utilization, mitigating environmental impacts, improving water management, reducing flood risks, enhancing water quality, engaging local communities, and strengthening climate resilience. Additionally, the study provides a clear understanding of suitable SWH locations, facilitating informed decision-making at project sites.