In October 2017, a landslide suddenly swept across a roadway in central California, cutting off access to the region and covering the road in hazardous and unstable soil and debris.
S.T Rhoades Construction, Inc. and the California Department of Transportation (Caltrans) enlisted GHD Digital’s Aerial and Location Intelligence Teams to conduct a topographical survey of the recent landslide in a remote area of central California.
By employing leading-edge Unmanned Aircraft Systems (UAS) technology, GHD Digital was able to safely complete the survey in only a matter of hours and deliver fast and accurate data to Caltrans.
This enabled the authority to quickly determine the extent of the shifting land, and then put out a bid for the removal of debris from the landslide.
The Challenge
Caltrans needed a rapid and accurate survey and assessment of the volume of a recent landslide in a remote area of the state.
However, the unstable land created by the disaster had led to extremely hazardous conditions for anyone attempting to access the area.
The Solution
The Aerial Intelligence Team used a Light Detection and Ranging (LiDAR) system mounted on an Unmanned Aerial Vehicle (UAV) to scan the area of the landslide. The LiDAR scan created a point cloud, a 3D representation of many points in space, leading to a 3D digital representation of the soil, debris and other site characteristics.
Meanwhile, the Location Intelligence Team collected on-the-ground survey data within locations that were safe enough to access. The teams combined their data to create a topographic map of the site.
The Aerial Intelligence Team also captured high-resolution aerial photography of the site and used it to generate an orthomosaic map, a large aerial map constructed out of many smaller pieces.
The Benefit
By responding to the needs of the client with a sophisticated digital solution, GHD Digital was able to provide safe and rapid capture of data and imagery within a hazardous environment.
This combination of aerial- and location-based surveying was far safer, faster, and more accurate than traditional approaches of surveying a disaster area.
GHD Digital provided Caltrans with accurate and actionable data, including topographic maps, aerial imagery and data files, which enabled the authority to immediately create bid documents and quickly begin the process of removing the debris from the site.