Continental Mapping was contracted by Tennessee DOT in 2014 to map an intersection improvement project using low altitude aerial imagery and high-resolution airborne lidar. The lidar was able to characterize terrain beneath vegetation and reduce the need for ground surveys. Continental Mapping delivered accurate 3D terrain data and digital mapping to expedite the project schedule. The project resulted in a hybrid photogrammetric and lidar terrain model suitable for road design software.

1. CONTINENTAL MAPPING
Mapping from Earth, Sky and Space
www.continentalmapping.com
Madison, Wisconsin
Indianapolis, Indiana
Kansas City, Kansas
St. Louis, Missouri
In February 2014, Continental Mapping was contracted to map an
intersection improvement project for Tennessee DOT (TDOT). This
intersection had been an area of concern given the deadly accidents
that have occurred there.
The project required large scale mapping using low altitude digital
imagery and high resolution airborne lidar. The airborne lidar was
essential to characterize the terrain beneath heavily vegetated areas,
thereby reducing the need for ground surveys to supplement the terrain
data. This expedited the project schedule by delivering accurate 3D
terrain data. Low altitude digital imagery was used to accurately survey
existing roadway features and pertinent structures within the designat-
ed area of interest.
The aerial survey was accomplished by using state-of-the-art
airborne digital sensors. The work was performed at an optimal
time frame when vegetation conditions were dormant. Project data was quickly
extracted from original digital sources and delivered within the project performance
schedule. The project resulted in current 3D digital mapping data including a terrain
file composed of both photogrammetric and airborne lidar elevations. This terrain file
was suitable for use with road design software in project adjusted coordi-
nates, per TDOT design specifications.
LOCATION: Grainger County, Tennessee
YEAR COMPLETED: 2014
OBJECTIVE: Provide high accuracy mapping to support final design
for an intersection improvement project
KEY POINTS:
• New airborne imagery and lidar for roadway design
• Hybrid photogrammetric and lidar terrain model
• Fast-track production schedule expediting 3D data to design team
• Digital data produced in project coordinates per TDOT design specs
Tennessee DOT Lidar & Photogrammetry