Posted on 25 October 2011
In the wake of Hurricane Katrina, the US Army Corps of Engineers were left with a number of problems. Firstly it was known the levee system had sustained damage, but the extent of the damage and locations of damaged sections were not known. Furthermore, much of the levee system was inaccessible on the ground due to flood water and debris. Secondly, a more detailed survey of the levees was needed to accurately calculate the work necessary to repair the levee system to a pre-hurricane state. The US Army Corps of Engineers (USACE) elected to contract John Chance Land Surveys, Inc. (JCLS), one of the Fugro group of companies, to carry out a levee survey of approximately 400 miles of levees in New Orleans East, Chalmette and Plaquemines Parish, using its FLI-MAP (Fast Laser Imaging Mapping and Profiling) system to fulfill both initial assessment and detailed survey requirements. JCLS and FLI-MAP had previously worked on a number of levee projects for the USACE, including the 125-mile Lake Ponchatrain and Vicinity Hurricane Protection.
By integrating state-of-the-art surveying techniques, such as LiDAR and high-resolution photo and video imagery, FLI-MAP offers a very fast, accurate and cost-effective solution to obtain the 3D geometry of water embankments and their surrounding environments. This is essential information to check the water defense for height and safety margins. The fact that the system is mounted underneath a helicopter makes it particularly suitable for surveying elongated flood defense structures that sometimes follow quirky layouts.
End users are very impressed with the new possibilities that FLI-MAP data can deliver to their management systems. When collected, the laser, photo and video data can be used and re-used for innumerable applications.