Bathymetric Mapping of Sediment Volume and Riverbed Changes for Optimized Dredging: A case study of Seplat Energies, in Mayuku River, Sapele LGA, Delta State, Nigeria

Abstract

This research investigates applying bathymetric survey techniques in evaluating seabed morphology and quantifying sediment volumes before and after a dredging operation. The primary objective was to assess navigational improvements and sediment displacement through hydrographic surveying and geospatial analysis. Using tide-corrected depth readings referenced to a standard datum, pre-dredging depths ranged from 2.0 to 2.7 meters, while post-dredging depths reached the target range of 4.0 to 4.5 meters. High-resolution bathymetric data were processed within a GIS environment, allowing accurate cut volumes and surface area computations, with pre- and post-dredging volumes estimated at 1,554,307.706 m³ and 1,702,694.232 m³, respectively. The study also examined post-dredging morphology to detect depth uniformity and areas of overcutting or undercutting. Findings highlight the critical role of geospatial tools in managing dredging operations and ensuring channel optimization for safe marine navigation.