Central Subway

San Francisco

Owner: San Francisco Municipal Transportation Agency

Prime: Barnard Impregilo Healy Joint Venture

  • Work Summary:

San Francisco Municipal Transportation Agency (SFMTA) set out to improve transit options for a densely populated neighborhood known for high public transportation ridership while also furthering business development.  Building these subway tunnels under a city that’s been well established since the “Gold Rush” of the 1800’s meant confronting structural and historical challenges above ground in addition to the soft ground and hard rock soil conditions.

Ballard supported hyperbaric needs that included Cal/OSHA requirements, and most importantly working within a very restrictive work site footprint.  Our team provided training for the J/V personnel to prepare them for entering the compressed air environment.  We provided support equipment that included a medical lock, shuttle and support for the equipment lock.  Emergency drills were performed on site on a regular basis.  Multiple hyperbaric interventions were performed by Ballard team members safely and without incident.

  • Project Notables:
    • Developed project specific hyperbaric operations manual
    • Assisted in acquisition of necessary Cal/OSHA variances
    • Evaluation, setup and integration of equipment into TBM systems
    • Provided on call compressed air workers for interventions
    • Provided contractor training