Land DevelopmentTransportationGovernment ServicesCoastal EngineeringLand Surveying

Contact Information

Michael J. Malloy, P.E.
Director of Transportation Services
440-365-4730
malloym@ksassociates.com

Surveying and Designing an Intersection Without Stepping Into Traffic Using 3D Laser Scanning

In 2013, the Ohio Department of Transportation commenced construction of the replacement of a four-span bridge on Abbe Road over I-90 in Sheffield Village. The project required the closure of Abbe Road and the diversion of traffic to alternate state routes.

Although the intersection of French Creek Road and East River Road was not part of the planned detour, this intersection is well-known among local motorists. Consequently, the intersection experienced a significant increase in traffic volume resulting in long waits and heightened driver frustration. In fact, two serious accidents were reported at the intersection during the first week of the bridge closure.

KS serves as Village Engineer for Sheffield Village and performed a traffic study, which warranted the installation of a temporary traffic signal. The first step in the signal design was to perform a survey of the intersection to update existing plans to accurately reflect existing conditions. The survey was challenging due to the large number of hard-to-reach utility lines. The new facilities had to clear these lines by specified amounts, and new signal heads had to be in clear sight for approaching motorists.

To overcome this challenge, KS deployed its Leica C10 3D Laser Scanner. Using the scanner, a field surveyor safely and singlehandedly acquired a comprehensive scan of the intersection — in one trip to the project site and within approximately one hour.

KS traffic engineers used the scan data to design the signal, which involved positioning new poles and supporting wires through a maze of existing utility lines.

The primary benefit of laser scanning on this project was the speed and ease of data capture -- particularly for the overhead utility lines. Laser scanning resulted in a fast delivery of a safe, signalized intersection and helped to reduce project costs. In addition, the scan data gave the designer greater flexibility in determining the locations for the new signal and support wires, which avoided design conflicts and repeat fieldwork.

For the right project, laser scanning can be a safe, fast and efficient alternative to conventional surveying.