Identifying Potential Rainwater Harvesting Sites for Sustainable Water Management Strategies in Urban Area

The expansion of impermeable surfaces has made urban regions more vulnerable to flooding, while water resources are depleting due to rising urbanization, population growth, and water usage. To mitigate water demand and prevent flood risks, it is imperative to utilize alternative water sources. The sustainable management of urban water resources presents considerable opportunities via rainwater harvesting (RWH). This project aims to implement RWH from road and roof surfaces at seven sites in the central district of Çanakkale Province, Türkiye, by establishing rain gardens and utilizing the collected rainwater for irrigation in urban recreational areas. The Analytic Hierarchy Process (AHP) and Geographic Information Systems (GIS) were used to find the best locations for RWH and to assess how much rainwater could be collected in different scenarios.The findings indicated that the AHP method designated 118 out of the 346 sites evaluated for RWH as suitable. The Barbaros neighborhood exhibited the highest potential for RWH; however, no suitable sites were identified in the Fevzipaşa and Namıkkemal neighborhoods. These findings highlight the effectiveness of RWH as a feasible strategy for urban water management for the city center of Çanakkale province. RWH can mitigate flood risks, reduce pressure on water resources, and improve urban cooling by decreasing surface runoff through landscape irrigation and rain gardens. The implementation of RWH devoid of energy requirements promotes sustainable water management and enhances the resilience of urban water systems.