I-5 Widening Project PS&E Segment 3 (El Toro Road to Alicia Pkwy)

Project Overview

The I-5 Widening Project from Alicia Parkway to El Toro Road (Segment 3) is part of a 6.5-mile corridor widening on I-5 from SR-73 to El Toro Road that was made possible through the cooperation of OCTA, Caltrans, OC Public Works, and Cities of Lake Forest, Laguna Hills, Laguna Woods, and Mission Viejo.  In Segment 3, the project proposed extending the second HOV lane from Alicia Parkway to El Toro Road, reestablishing existing auxiliary lanes and constructing new ones, and improving several existing on-ramps and off-ramps. Additionally, the project proposed the establishment of full standard widths and continuous access for the HOV lanes with no buffer throughout the project limits.

TRC led the preparation of the engineering plans, specifications, and estimates for freeway widening, ramp reconstruction, widening of Aliso Creek Bridge and El Toro Road Undercrossing, replacement of Los Alisos Overcrossing, various retaining and sound walls along the I-5 mainline and the extensive construction staging and detour designs. The project required relocation of SCE transmission line and a 42″-water pipeline in addition to extensive drainage facility modifications.

The I-5 freeway crosses over Aliso Creek with a multi-span bridge. The Aliso Creek alignment will be impacted due to widening of the bridge over the creek. TRC developed a hydraulic study for the Aliso Creek channel, prepared an updated floodplain map, and developed design to stabilize the channel invert for scour control.  The hydraulic study was reviewed and approved by OC Public Works.

Value Added: TRC’s innovative geometric design by shifting freeway alignment to avoid significant ROW impacts produced significant savings in project cost and schedule.