Stormwater management in the Acibadem and Hasanpaşa neighbordoods: a case study from Kadiköy İstanbul

Today, the rapid pace of urbanization has led to the replacement of natural surfaces with impervious structures, significantly disrupting the hydrological cycle in urban areas. The decrease in permeable surfaces prevents rainwater from infiltrating into the ground, thereby hindering the recharge of groundwater resources and increasing surface runoff, ultimately disturbing the natural water cycle. This shift contributes to increased water pollution, the deterioration of the soil moisture balance, and a heightened risk of flooding. The growing population, widespread urban development, industrialization, and intensified human interventions in nature—combined with global climate change—have further exacerbated flood risks (Dilley, 2005). As a result, the amount of accessible clean water, air, safe food, and green spaces has significantly diminished in urban environments. In this context, protecting and enhancing the natural water cycle is of critical importance for ensuring the sustainability of urban areas. Promoting the infiltration of rainwater into the soil, collecting and utilizing stormwater through ecological approaches, and maintaining the hydrological functions of cities are central objectives of sustainable stormwater management. Planning and implementing strategies in line with these goals contribute to both ecosystem health and the overall quality of urban life. In this study, the neighborhoods of Acıbadem and Hasanpaşa have been selected as focus areas due to their status as densely built-up urban zones in Istanbul, characterized by high impervious surface ratios and the resulting risk of surface runoff and flooding. Both neighborhoods exhibit limited opportunities for natural infiltration, inadequate conventional infrastructure, and a pressing need for sustainable solutions in stormwater management. Moreover, the diversity of current land use (residential, educational, parks, etc.) and the presence of climate adaptation policies supported by the municipality make these neighborhoods suitable case studies for evaluating the applicability of nature-based solutions. Keywords: Stormwater Management, RationalMethod, AHP, Suitability Analysis