The BOH/GEC Team provided engineering and construction services for this urban freeway interchange Design-Build project which provides improved access to College Dr from westbound I-10 and I-12.
GEC implemented an innovative design which simplified the traffic movement on a new alignment that addressed impacts to surrounding areas and which was unforeseen in previous studies and design. This design also reduced the footprint established by NEPA documentation. The Team’s design improves the flow of traffic and safety by improving the I-10/I-12 merge through the elimination of lane changes that must occur when I-10 WB traffic exits at College Drive. GEC’s design achieves this by realigning the two existing I-12 WB through lanes to more closely follow the I-12 EB existing alignment, completely replacing the I-10 WB Overpass Bridge with a new structure at a bridge width which accommodates both the I-10 WB through lanes and the I-10 WB College Drive exit ramp, and utilizes the existing I-12 WB pavement for the I-12 WB College Drive exit ramp. Improvements to the I-12/I-10 exit lane with College Drive intersection are also included.
GEC provided environmental compliance plans and permitting services, including adhering to and updating NEPA Documentation, environmental mitigation, wetland mitigation, SWPPP, tree impact plan, and permit modification services. GEC also revised the existing network study and conceptual alternatives analysis (line and grade alternatives), ROW acquisition plan, hurricane preparedness and evacuation plan, safety plans, and the Interchange Modification Report (IMR). GEC also provided public/stakeholder outreach and conducted public meetings.
GEC was the task lead for road and bridge design, in addition to design of the new I-10 westbound bridge and rehabilitation plans for the I-12 to I-10 Flyover and Essen Lane overpass. GEC also designed the widening of the I-10 westbound bridge over Ward Creek. The new bridge structure is comprised of three 55’ long simple spans composed of rolled steel girders with a cast in place concrete deck. GEC’s design services included the rehabilitation of the existing bridge and replacement of the deck joints. GEC’s design of the bridge also accommodated a sound barrier.
The project required that 5 lanes of traffic be maintained at all times though this heavily traveled corridor. GEC staff developed bridge plans to construct the widening and rehabilitation in multiple phases to maintain the required 5 lanes of traffic. The project required a level 4 Transportation Management Plan (TMP).
GEC provided the roadway construction plans for this project and was responsible for the geometric layout for the entire project, ensuring conformance to DOTD and AASHTO standards. GEC provided hydraulic design which included the design of several subsurface drainage systems and cross drains. GEC also performed hydraulic channel analysis to ensure the project did not negatively impact the surrounding areas. An opinion of probable cost for the project was also calculated by the GEC team and provided to the contractor.
In addition to bridge and roadway design, GEC completed a photometric report and lighting plans for the design-build project. The lighting design consists of both high mast and low mast lighting. This required review of engineering shop drawings and equipment submittals from the electrical contractor.
Construction began in May 2021 and the safer traffic configuration was opened to traffic in April 2025.
