Flood Hazard Zonation Using an Integrated GIS–AHP Approach in the Bardaskan Watershed, Khorasan Razavi Province, Iran

Document Type : Original Article

Authors

1 Associate Professor of Geomorphology, Department of Geography, Faculty of Law and Social sciences. Payame Noor University, Tehran, Iran.

2 Assistant Professor of Geomorphology, Department of Geography Education, Farhangian University, Tehran, Iran.

3 Master of Science in Urban Planning, Ministry of Interior, Khorasan Razavi Provincial Government, Bardaskan Municipality, Iran

10.22034/hyd.2026.71506.1839

Abstract

Floods are critical hazards in arid and semi-arid regions, causing substantial damage to settlements and infrastructure, particularly following torrential rainfall and rapid runoff concentration. Consequently, identifying and zoning flood-prone areas plays a pivotal role in risk management and spatial planning. This study aims to evaluate and map flood hazards in the Bardaskan watershed using an integrated approach of Geographic Information Systems (GIS) and the Analytic Hierarchy Process (AHP). A comprehensive set of hydrological, geomorphological, and environmental criteria, including slope, distance from streams, drainage density, land use, soil permeability, and precipitation characteristics, was analyzed. The relative weight of each criterion was determined using the AHP method. By overlaying these spatial layers in a GIS environment, a flood hazard zonation map was generated, classifying the watershed into five categories from very low to very high risk.

The findings reveal that factors associated with the drainage network and precipitation patterns, notably distance from streams and short-duration rainfall events, exert the greatest influence on the spatial configuration of flood hazards. Downstream sections and areas adjacent to main streams exhibit the highest potential for flood occurrence. Model evaluation using the Receiver Operating Characteristic (ROC) curve yielded an Area Under the Curve (AUC) value of 0.782, demonstrating acceptable performance in delineating flood-susceptible zones.

Overall, this research illustrates that integrating GIS and AHP provides an effective framework for spatial analysis of flood hazards, despite limited hydrometric data. The resulting map serves as a robust scientific foundation for runoff management, land-use planning, and mitigating flood damages in Bardaskan.

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Articles in Press, Accepted Manuscript
Available Online from 12 May 2026
  • Receive Date: 11 February 2026
  • Revise Date: 11 May 2026
  • Accept Date: 12 May 2026