Integrated hydrographic survey for proposed Jetty location along Benin River at Oghara Delta State, Nigeria

This study utilised two hydrographic survey methods for a proposed jetty localisation. In the first method, a hydrotrac single-beam echo sounder (SBES) provided the river depth information, while in the second method, a StarFish 990F side scan sonar (SSS) was deployed to sweep across the river bottom in order to x-ray and confirm the presence of any impediments to smooth navigation. The maximum and minimum depths obtained are 1.3 m and 14.2 m. The revelation of the existence of enough depth for berthing and movement of vessels are concentrated at the central region of the river. The volumetric analysis of the water column within the confined river section estimated with seven methods as required by the job prescription showed that the grid method has the highest volume of 1,487,113 m 3 , while the minimum volume of 1,487,037 m 3 was obtained using Simpson’s 3/8 method. The discovered tracked wrecks were at distances of 181.7 m and 169.4 m from the head of the proposed jetty reference point. The debris discovered are located at distances 225.0 m, 224.4 m, and 82.9 m. Based on jetty’s dimensions, it implies that no obstruction could prevent its construction at the specified location. This research also revealed that every wreck locations, whose distances and positions were established and provided, poses a risk to vessel movement. Hence, the removal of these wrecks is recommended to enhance safe navigation.