Project Description
Parsons was selected as part of a joint venture team to design and build the Southeast Corridor Transportation Expansion Project (T-REX), the largest transportation contract in Colorado history. This multimodal design-build project includes highway, light rail transit, pedestrian, and bicycle facilities along the I-25 and I-225 corridors in Denver. As design manager, Parsons was responsible for approximately 50% of the total project design.
The design scope comprises civil and structural design, including permanent and temporary (detour) facilities, transit buildings, transit parking, and traffic maintenance during construction.
Parsons' design team provided an innovative reconfiguration concept for the I-25/I-225 interchange. This design moved light rail trains from the highest level of the interchange to the lowest level that resulted in significant cost savings, aesthetic improvements, and improved temporary traffic control.
Parsons was the primary designer of 19 miles of double-track light rail transit along I-25 and I-225 including 13 new transit stations, park-and-ride lots, three new parking garages, a new operations control center, power and signal systems, and a supervisory control and data acquisitions system for the existing transit lines. Parsons also performed testing and commissioning of these systems. These highway and transit improvements will bring long-term transportation relief for some of metro-Denver’s fastest-growing and most congested areas.
T-REX comprises over $60 million of intelligent transportation system (ITS) elements, including dynamic message signs, closed circuit television (CCTV) cameras, freeway and arterial detection (to monitor surface street congestion), ramp metering, a communications network, an Interim Traffic Management Center (ITMC) housing an Incident Information Management System, and Public Information Web channels. The project’s web site informs the public of real-time traffic conditions.
Parsons designed all of the ITS elements in close coordination with the contractor. The overall goals are optimum freeway traffic management and real-time display of travel conditions on both I-25 and the surrounding surface street system.
The project was completed nearly two years ahead of schedule and within budget. The Light Rail System was placed in service in November 2006. The fast-track design/build method saved several years of construction time.
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