High Tech Aerial Surveys

March 17, 2015

An aerial survey of the project corridor is being done that will complement the on-the-ground field work. Surveying and mapping the physical and geographical features of the corridor is a critical component of the project. Surveyors will use cutting edge technology to measure features of the earth to establish the location of property lines, ensure the accuracy of construction projects, and produce updated maps for the team to use. Utilizing these minimally invasive aerial methods, the team is able to limit the need for field survey groups to perform on-the-ground measurements.

From January to April, aerial photography and LIDAR imagery, which uses light from a laser, will be captured along the project corridor by professional flight crews. Individual photographic images (from LIDAR or photographs) will be put together as a panorama based on known ground points. LIDAR data, also known as “light imaging” works in a fashion similar to RADAR. The LIDAR sensor sends out millions of pulses of visible light and uses the return time to calculate the distance from the aircraft. LIDAR is unique in that it is able to penetrate even very small openings in a tree canopy. These distances from the aircraft are used to calculate the shape or terrain of the earth’s surface. The aerial photography and LIDAR data are combined to create a three dimensional model for use by engineers to analyze potential alternatives and to design railway, roadway, structural, and drainage features. 

About the photo: A “color shaded relief” of the LIDAR information. Colors are assigned to the LIDAR points based on their elevation. The colors at different elevations provide the three dimensional visual effect and define the underlying terrain.