Eastern Transportation Corridor

The Corridor begins at the Riverside (91) Freeway, west of Gypsum Canyon Road, travels through Gypsum Canyon toward Irvine, splitting into two legs at Santiago Canyon Road. The east leg joins Interstate 5 at the Laguna (133) Freeway and the west leg merges with Jamboree Road south of I-5 in Irvine. Initial construction began in June 1995 and was completed in February of 1999, 14 months ahead of schedule. Silverado Constructors built 28 miles of toll way, including 11 interchanges, 65 bridges and 300 linear miles of utilities and drainage systems. The $712.6 million project involved moving 55 million cubic yards of earth, laying 1.3 million tons of asphalt and pouring 450,000 cubic yards of concrete. The project also included the widening of I-5, Highway 91 and the construction of additional lanes on 2½ miles of the existing Foothill Toll Road. SB&O efforts included retracing and supplementing the horizontal and vertical control using Global Positioning System (GPS) and conventional survey methods. Topographic surveys included geotechnical surveys, as-builts, design surveys, quantity checks by field cross-sections utilizing conventional and real-time GPS survey methods, and settlement monitoring. SB&O was responsible for all construction staking and preparation of the staking notes and grades associated with grid grades, slope stakes, paving, storm drain and utility grade sheets, bridge layout coordinates, and pavement widening grades for all construction staking.