Bay Area Rapid Transit, San Francisco, California USA

3D Imagery and LiDAR survey delivers authoritative asset information to BART’s enterprise systems

Business Challenge

The Bay Area Rapid Transit (BART) organisation provides heavy rail public transit services connecting San Francisco with cities in the East Bay and suburbs in northern San Mateo County. The BART network also includes the famous Transbay Tube; a 6-mile underwater rail tunnel that was commissioned in 1974.

BART is busy implementing new enterprise asset management and enterprise geographic information system (eGIS) to help it plan and maintain the network as it grows from a patronage of 450,000 passenger trips today to an anticipated passenger service of 650,000 trips. BART identified that a transit asset data collection project was needed to underpin the success of its major IT system initiatives and growth planning.

As a specialist supplier of rail asset information, GT was tasked with collecting 3D panoramic imagery and LiDAR datasets across the BART network and using specialist tools and techniques to extract current asset information from these datasets.

Services Overview

The BART heavy rail commuter network is comprised of 208 track miles, of which 74 track miles are underground.

In preparation for data collection GT mobilized its camera and laser equipment onto a BART rail maintenance vehicle. Accurate inertial positioning equipment was also deployed so that any data recorded through parts of the network with little or no GPS (e.g. long underground sections such as the Transbay Tube) could be mapped and assigned accurate milepost and stationing values.

GT’s rapid rail data acquisition technology was able to record all project data over three recording days with minimal disruption to revenue services.

A comprehensive track data asset dictionary was also developed with the client that included all of the critical infrastructure and features that BART needed to have mapped.

A further two month period was then required by GT’s feature extraction team to fully populate the BART rail asset data dictionary. All assets are described with GPS, mileage and references to the 3D panoramic imagery, which BART now distributes to its staff through its eGIS.

Outcomes

– Delays to revenue services were minimized as data was collected during normal revenue operation

–  BART has access to authoritative track asset data for operations, planning and maintenance purposes

– Staff can perform virtual site visits at any time using the 3D panoramic imagery recorded on the network

– LiDAR point cloud data can be leveraged for design and engineering level investigations.