Istanbul’s most densely populated districts face the highest flood risk, according to a new artificial intelligence-based study conducted by Istanbul Technical University (ITU) in collaboration with the Istanbul Disaster Coordination Center (AKOM), highlighting the growing impact of climate change and rapid urbanization on the мегacity.
The study, titled “District-Based Flood Risk Mapping of Istanbul,” introduces a first-of-its-kind approach in Türkiye, using an AI-driven decision-support algorithm to assess flood risks at the district level.
The model evaluates hazard, exposure and vulnerability indicators to determine where flooding is most likely to occur and where its impact could be most severe.
According to the findings, central districts with high population density and extensive urban development rank at the top of the risk scale. Fatih, Gaziosmanpaşa, Bağcılar, Güngören and Beyoğlu emerge as the most vulnerable areas, reflecting a pattern where human concentration and built environments amplify disaster exposure.
Researchers underline that flood events have become more frequent and intense in recent years, largely driven by climate change.
However, in Istanbul, these environmental pressures are compounded by structural challenges, including insufficient drainage infrastructure and widespread concrete surfaces that prevent rainwater absorption. As a result, heavy rainfall increasingly translates into flash floods and waterlogging.
Project coordinator associate professor Ömer Ekmekcioğlu emphasized that the research focused on Istanbul due to its status as Türkiye’s most populous city and its growing exposure to climate-related risks.
He noted that the analysis incorporated a wide range of variables, including approximately 15 hazard indicators and nearly 20 factors related to vulnerability and exposure.
By integrating these datasets, the research team was able to map the spatial distribution of flood risk across the мегacity with high precision. The AI model, trained on historical flood data and environmental parameters, achieved an estimated accuracy rate of 90% to 95% in predicting flood-prone areas.
The findings also reveal a geographical imbalance in risk distribution. Districts on the European side generally face a higher flood risk compared to those on the Anatolian side. This disparity is largely attributed to denser urbanization patterns and higher population concentrations in key parts of the European side.
While some peripheral districts, such as Adalar, Şile, Silivri, Sarıyer and Çekmeköy, were identified as having relatively low flood risk, experts caution that even low-risk areas are not immune to extreme weather events.
A critical insight from the study is that only around 10% of Istanbul’s total surface area falls into the high-risk category. However, these areas are home to a significant share of the city’s population, effectively magnifying the potential human and economic impact of flood events.
Ekmekcioğlu stressed that urbanization plays a central role in shaping flood dynamics. In districts where natural land has been replaced by impermeable surfaces, rainwater flows rapidly across streets rather than being absorbed into the ground, increasing the likelihood of sudden flooding.
To address these challenges, the study recommends a shift toward nature-based solutions that align urban infrastructure with environmental processes. Proposed measures include rainwater harvesting systems, the expansion of permeable surfaces and the development of rain gardens designed to absorb excess water.
In particular, rooftop rainwater collection systems are highlighted as a practical intervention. By capturing and storing rainfall, these systems can reduce immediate runoff while also contributing to water reuse strategies, offering a dual benefit for urban sustainability.
Experts underline that such measures will be critical as Istanbul continues to confront the combined pressures of climate change and urban growth. The study serves as a data-driven roadmap for policymakers, emphasizing the need for proactive planning and targeted investments in high-risk districts.
