IIARD International Institute of Academic Research and Development

WORLD JOURNAL OF INNOVATION AND MODERN TECHNOLOGY (WJIMT )

E-ISSN 2504-4766
P-ISSN 2682-5910
VOL. 8 NO. 4 2024
DOI: 10.56201/wjimt.v8.no4.2024.pg90.112

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Comprehensive GIS-Based Flood Risk Assessment of Vulnerable Areas in Anambra State, Nigeria

Odoh, Benard Ifeanyi and Nwokeabia, Charity Nkiru

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Abstract

Flood risk assessment is critical for effective flood management and mitigation strategies. Understanding spatial variability in flood susceptibility helps in designing targeted interventions. This study aims to evaluate flood risk in a specified area by integrating multiple hydrological and topographical parameters. The assessment incorporates drainage density, slope, land use and land cover (LULC), rainfall, elevation, and proximity to rivers and roads. Data were analyzed to categorize regions into five flood risk levels: very low, low, moderate, high, and very high. The study reveals significant spatial variability in flood risk. High-risk areas, constituting 37.28% of the study area, are primarily near drainage networks and steep slopes. Regions with low to moderate drainage density, covering 40.25%, are prone to waterlogging, while areas with high drainage density, accounting for 59.75%, manage local runoff but may exacerbate downstream flooding. The LULC analysis shows that forested areas (43.62%) mitigate flood risk, whereas built-up areas (35.20%) increase it. Higher rainfall in the southern part of the study area and varied elevation also influence flood risk distribution. High-risk regions need robust flood defenses and efficient drainage systems. Sustainable land management practices and advanced flood control measures are essential for mitigating flood risk, particularly in high rainfall and steep slope areas. This study uniquely combines multiple parameters to provide a comprehensive flood risk assessment, offering valuable insights for targeted flood mitigation strategies and enhancing regional flood resilience.

keywords:

Drainage Density, Hydrological Studies, Slope Analysis, Spatial Variability,

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