Hawthorne Transit Tunnels

An Innovative Method That Changed the Industry

Precision helped design, build, and operate a mobile manufacturing facility for the precast segmental tunnel liners used to construct the first steel fiber-reinforced concrete passenger tunnel in the United States.

Precision assembled a world-class team to support the project, and the results included an innovative method for constructing tunnels at a cost far below industry norms. The project changed the domestic tunneling industry and ushered in more economically viable tunnel development throughout the country.

Precision also contracted leading concrete engineers to finalize the concrete design and assembled a staff of experienced ring segment casting professionals to begin production.

Precision went on to serve as the General Contractor responsible for design, construction, and management of the precast concrete tunnel liner segment production facility, responsible for managing ring segment production itself.

Construction scopes for this project included demolition, surveying, site utilities, lighting, excavation, foundations, climate control structure, temperature/CO2 controller, overhead gantry crane, casting molds, and on-site concrete batch plant with accompanying rail system for transporting ring segments into the tunnel.