Footbridge and Riverbed Survey 13 October 2023 /Posted byStephen Lainson / 0 Case Studies Combining 3D SONAR, LASER and underwater video, a comprehensive 3D survey recorded the condition of the bridge structure and mapped the contour of the riverbed, revealing areas where scouring and deposition were occurring. Download PDF About the author: Stephen Lainson Stephen is the Managing Director of Fortis Remote Technology, a Mechanical Engineering business, in Cumbria.