LiDAR (acronym for “Light Detection And Ranging”) is a scanning and ranging laser system that produces accurate Digital Terrain Models that can be used for contour modeling. LiDAR has the capability to provide accurate surface modeling in places previously not possible, returning data accurate up to 0.5 foot.

While flying over the project area, a laser sweeps back and forth across the ground scanning the surface and its features. After making contact with the ground, the beam energy returns to the aircraft, producing point data as well as infrared images. After all the data is collected, it is processed into a point-derived image.
Each point, which is three-dimensional, can be viewed in any direction desired, providing a 3D representation of a scene. This gives the ability to look at a segment vertically, sideways, or to rotate the canvas for different views—and all from only one flyover. All of this data can be processed in a matter of weeks, unlike manual photogrammetric techniques that can take months before they are completed.
Colorful LiDAR image of a river

LiDAR is perfect for collecting data in heavily-forested areas and river reaches, and it is works well at night because of the absence of thermal radiation, lower turbulence, and less wind.

Over the last two years, Surdex-lead teams have acquired and processed over 30,000 square miles of LiDAR data into bare earth and surface format. This includes extensive work in Missouri and Oklahoma and prior work in the State of Texas.

Leica ALS-70HP kHz LiDAR System

Leica ALS-70HP kHz LiDAR SystemSurdex owns and operates a Leica ALS-70HP kHz system that provides rapid and accurate generation of digital terrain data. Surdex processes all LiDAR data through a custom designed post processing system consisting of commercial software products produced by TerraSolid and custom software tools developed in-house by Surdex. The ALS70HP specifications are:

  • 500 kHz pulse rate
  • 200 kHz scan rate
  • Unlimited pulse returns
  • Up to three intensity returns
  • Selectable scan patterns: sinusoid, triangle, and raster
  • Automatic adjustment of scan rate for uniform along-track spacing
  • Reduced noise
  • Improved range correction