Evaluation of Lidar for Highway Planning, Location and Design

Surface terrain information is required to economically site new or relocate existing infrastructure facilities and make final design plans. Currently, field surveying and photogrammetric mapping are the most widely used methods to acquire these data. However, these methods are time and resource intensive as significant data collection and reduction is required to provide the level of detail necessary for facility location and design. Light Detection and Ranging (LIDAR) is a relatively new alternative technology to obtain terrain information more efficiently. With LIDAR, data can be collected under a variety of environmental conditions, including low sun angle, cloudy skies, and even darkness, resulting in expanded windows for data collection. While less accurate than photogrammetric mapping, LIDAR presents the opportunity to expedite the highway location and design process by providing designers with preliminary terrain information earlier in the process. This paper presents a proposed methodology for utilizing LIDAR in conjunction with photogrammetric mapping to speed up highway location and design activities, including estimates of time and cost savings.