GEOSPATIAL ASSESSMENT OF FLOOD RISK AND SOIL EROSION IN ABA & ENVIRONS, SOUTH EASTERN.

Flooding remains a critical environmental challenge, particularly in regions with rapid urbanisation and poor drainage infrastructure. Understanding flood susceptibility through geospatial analysis is essential for effective risk management and disaster preparedness. This study assesses flood risk and soil erosion dynamics in Southeastern Nigeria using Geographic Information Systems (GIS) and Remote Sensing. The objective is to classify flood-prone areas and propose suitable mitigation strategies based on environmental parameters. A multi-criteria approach was applied using Digital Elevation Models (DEM), slope analysis, Topographic Wetness Index (TWI), drainage density, land use/land cover (LULC), and annual rainfall data. The weighted overlay method in ArcGIS was used to classify the study area into five flood risk categories: very low, low, moderate, high, and very high. The analysis revealed that moderate-risk areas cover the most significant portion of the study area (106.12 km²), while high-risk zones span 51.14 km², primarily in low-lying regions with impervious surfaces. Very high-risk areas, totalling 6.03 km², were concentrated along riverbanks and poorly drained areas. In contrast, low-risk areas covered 81.74 km², benefiting from adequate drainage, and very low-risk zones accounted for 13.30 km². The study highlights the influence of urbanisation, topography, and hydrology on flood susceptibility. Effective land-use planning, afforestation, and improved drainage infrastructure are critical for mitigating flood risks. The integration of geospatial techniques provides valuable insights for flood risk assessment, aiding in proactive flood management strategies and urban planning. This research offers a spatially explicit flood risk classification, integrating multiple environmental variables to enhance predictive accuracy and inform sustainable flood mitigation efforts.