Osman Sonmez’s research while affiliated with Sakarya University and other places

Floods pose significant risks worldwide, impacting lives, infrastructure, and economies. The Susurluk basin, covering 24,319 km² in Türkiye, is highly vulnerable to flooding. This study updates the flood management plan for the basin, integrating hydrological modeling, GIS-based flood mapping, and early warning system evaluations in alignment with the EU Flood Directive. A total of 503 hydrodynamic models (226 one-dimensional and 277 two-dimensional) were developed, analyzing 2116 km of stream length. As a result of the evaluation, the capacities of only 33 streams were found to be sufficient. Flood hazard and risk maps for the Q50, Q100, Q500, and Q1000 return periods identified the remaining 470 high-risk locations as requiring urgent intervention. Economic risk assessments revealed significant exposure of critical infrastructure, especially in urban areas with populations over 100,000. Furthermore, the study introduces a prioritization framework for intervention that balances socioeconomic costs and environmental impacts. Economic damage assessments estimate potential losses in critical infrastructure, including residential areas, industrial zones, and transportation networks. The findings highlight the importance of proactive flood risk mitigation strategies, particularly in high-risk urban centers. Overall, this study provides a data-driven, replicable model for flood risk management, emphasizing early warning systems, spatial analysis, and structural/non-structural mitigation measures. The insights gained from this research can guide policymakers and urban planners in developing adaptive, long-term flood management strategies for flood-prone regions.

This study details the design and implementation of a real-time river monitoring station established on the Sakarya River, capable of instantaneously tracking water levels and flow rates. The system comprises an ultrasonic distance sensor, a GSM module (Global System for Mobile Communications), which enables real-time wireless data transmission to a server via cellular networks, a solar panel, a battery, and a microcontroller board. The river monitoring station operates by transmitting water level data collected by the ultrasonic distance sensor to a server via a communication module developed on a microcontroller board using an Arduino program, and then sharing these data through a web interface. The developed system performs regular and continuous water level readings without the need for human intervention. During the installation and calibration of the monitoring station, laboratory and field tests were conducted, and the obtained data were validated by comparison with data from the hydropower plant located upstream. This system, mounted on a bridge, measures water levels twice per minute and sends these data to the relevant server via the GSM module. During this process, precipitation data were utilized as a critical reference point for validating measurement data for the 2023 hydrological year, with changes in precipitation directly correlated with river water levels and calculated flow values, which were analyzed accordingly. The real-time river monitoring station allows for instantaneous monitoring of the river, achieving a measurement accuracy of within 0.1%. The discharge values recorded by the system showed a high correlation (r² = 0.92) with data from the hydropower plant located upstream of the system, providing an accurate and comprehensive database for water resource management, natural disaster preparedness, and environmental sustainability. Additionally, the system incorporates early warning mechanisms that activate when critical water levels are reached, enabling rapid response to potential flood risks. By combining energy-independent operation with IoT (Internet Of Things)-based communication infrastructure, the developed system offers a sustainable solution for real-time environmental monitoring. The system demonstrates strong applicability in field conditions and contributes to advancing technologies in flood risk management and water resource monitoring.