The L.A. Underground: Mobile LiDAR Mapping for Rail Tunnel Retrofit
Los Angeles County Metropolitan Transportation Authority (Metro) intends to accommodate increased service levels on the Metro Red and Purple Lines. To achieve this, the Division 20 Portal Widening and Turnback Facility Project necessitates retrofitting certain features in the twin-tunnels between Union Station and the Division 20 Rail Yard. The design team, led by T.Y. Lin International Group, required detailed, survey-grade mapping for more than 1,900’ of subterranean rail. The design team surveyor, Wagner Engineering & Survey, Inc. (WES), based on prior projects on-going relationship, contacted R.E.Y. Engineers, Inc. to provide Mobile LiDAR acquisition and mapping for the tunnels, as well as a significant portion of the Division 20 Rail Yard. This presentation will discuss the challenges, acquisition, data quality and deliverables to the project team.