In November 2006 one of the most innovative transportation projects in the Americas was completed at Denver, Colorado.

A US$1.75 billion combined public light-rail and highway construction project, developed to avoid increasing congestion, the Transport Expansion (T-REX) project is innovative not because of cutting edge technology (although this was used) but because of its approach and simplicity.

Its innovation is in the unique collaboration between different government agencies and a simple idea to run a highway and light rail side-by-side, enabling commuters the option of travel by car or train throughout the 19 mile stretch - a choice for car drivers to leave the highway, perhaps if it is too congested, and catch the light-rail train instead.

A 1992 congestion study revealed traffic volume through the Interstate-25 corridor between downtown Denver and the Denver Technical Center exceeded the maximum capacity of 180,000 vehicles per day.  To make matters worse, population and job growth in both areas were projected to explode by 2012.  With the threat of gridlock on the horizon, Denver's Regional Transportation District, the Colorado Department of Transportation, the Federal Highway Administration and the Federal Transit Administration partnered to plan the largest multi-modal transportation project in the history of the State of Colorado.

The evolution of the agencies' joint efforts produced a plan to improve 17 miles of highway by adding lanes, reconstructing major interchanges, widening bridges, and improving shoulders, acceleration/deceleration lanes and on/off ramps while simultaneously adding 19 miles of double-track light rail and supporting facilities.  Hence, a multi-modal monster was born.

Tackling T-REX

The magnitude and complexity of T-REX demanded an experienced engineering and construction team with significant labour and material resources and the financial stability to see the project through to completion.  The Southeast Corridor Constructors (SECC) team, led by Kiewit Construction and Parsons Transportation Group, awarded EMCOR Group - which has expertise in multi-modal transport projects through its Dynalectric subsidiary - the role of primary electrical contractor. The only way to effectively conquer a monster is to carefully coordinate an attack so EMCOR assembled a design-assist management and supervisory team to tackle three major elements of T-REX.

The Light Rail Train (LRT) scope included 19 miles of underground concrete encased conduit and cable ductbank to provide power to the train's 17 traction power substations (TPSS) and full communications and power for 13 new train stations, 36 elevators, 3 parking garages, 10 park-and-ride lots and 6 pedestrian bridges.

The Intelligent Transportation System (ITS) required installation of and power to more than 500 devices and signs for the freeway and arterial vehicle detection system (FVDS/AVDS), closed circuit television (CCTV), dynamic message signs, highway advisory radio, off-ramp detectors and ramp meters; all connected by 20 miles of fiber optic cable to enable center-to-field communications.

The Lighting/Traffic Signalisation scope called for installation of 300 new freeway median and arterial high mast pole lights; 1,500 train station, garage, parking lot, emergency egress, under bridge and pedestrian bridge lights; and temporary relocation of traffic signals at every major Interstate-25 corridor intersection between Broadway and Lincoln Avenue.

In an effort to achieve the agencies' goals to support small and disadvantaged businesses, EMCOR employed over 50 vendors and subcontractors to supply materials and perform various portions of the work.  Subcontractors participated in every aspect of the work from estimating to procurement to layout and coordination to supervision and installation to project management and job cost control.  EMCOR delegated responsibilities and gave multiple small businesses the opportunity to broaden their experience and be an integral part of this high-profile project.

Coordination

SECC proposed an aggressive schedule.  Construction began in October 2001 and SECC planned completion by September 2006, a full 22 months ahead of the agencies timeline.  In addition to bi-weekly project-wide design and construction coordination meetings, EMCOR held weekly coordination meetings with project managers, engineers, field supervision and subcontractor partners during which a rolling 5-week look ahead schedule was updated and project progress reviewed.  Because it was posted from ceiling to floor on the office wall, the rolling schedule became a project focal point and every project manager, field supervisor, subcontractor and vendor was reminded of their responsibilities every time they walked in the door.

The project boundaries were far-reaching from Denver south to Douglas County and east to Aurora.  In order to coordinate right-of-way, permitting and inspections, EMCOR had to collaborate with seven different municipalities and jurisdictions, not to mention the neighborhood communities. The LRT power and communication ductbanks alone were located and installed in the cities of Aurora, Denver, Englewood and Greenwood Village as well as Arapahoe and Douglas counties and the ITS stretched a bit further to include the City of Littleton.  Depending upon the location of work, EMCOR had to coordinate with up to three jurisdictions for permitting and inspections for single section of ductbank.  Additionally, EMCOR held and participated in hundreds of community meetings to address noise, debris, parking, and other concerns of neighbours to the T-REX project.

Contractors are familiar with the 'call before you dig' utility protocol, but EMCOR had utility companies on speed dial.  Virtually every aspect of the work was underground, so coordination with Xcel Energy, Qwest, and other utilities was absolutely critical.  EMCOR worked with Xcel almost daily for the first three years of the project to identify power requirements, locations for power tie-in, locations of existing utilities and delineation of installation responsibilities in terms of where Xcel left off and EMCOR picked up.  The LRT alone required locations of 65 points of service to provide power for TPSS, relay houses and station platforms and more than 315 points of service were coordinated by EMCOR overall.

Complications Underground

More than 2 million feet of power and communications conduit was run underground on both sides of Interstate-25, but EMCOR was not allowed to tear up the highway.  And, because the arterial streets were designated as alternate routes to the Interstate-25 corridor, digging through the side streets was also restricted.  These restrictions complicated the typical method of trenching because each roadway encountered forced EMCOR to abandon the trencher to bore underneath the street. 

Every element of work was affected:  centre median lighting required power from the ductbank, so boring was conducted from the shoulder to the center median at every major intersection from Colorado Blvd & Interstate-25 south to Lincoln Avenue; numerous sites required boring where ITS freeway vehicle detection system devices were located along the highway, including a section from 6th Avenue south to Broadway to enable tie-in of the new fiber optic backbone into the CDOT traffic management control center; and boring from Xcel transformers to the LRT TPSS and/or from the TPSS to the feeder poles for the train power.   The quantity of boring required was so great that to make certain ample equipment, operators and field support were available for concurrent activities; EMCOR utilised four different subcontractors to accomplish more than 10 miles of boring.

Sunlight to the Rescue

The AVDS and FVDS portion of the ITS required installation of hundreds of devices both on and off the Interstate-25 corridor to monitor speed, volume and occupancy on the freeway and arterial roadways.  But the cost of bringing power to some of the cameras and devices was highly cost prohibitive because there were not power sources available close by.  A more cost effective solution was found in sunlight.  Nearly 100 cameras were located in areas lacking accessible electrical power and instead, were installed to operate on solar power.  Additionally, monitoring of AVDS was transmitted via wireless communications system.  Modems and transceivers were installed to transmit large volumes of video and data information every 20 seconds from each AVDS, FVDS and CCTV device.  This data was then collected, collated and posted on the internet for the public to view real-time traffic conditions on Interstate-25 and arterial roadways.

Safety Over Productivity

The T-REX project team understood that while it was critical to remain on schedule, incidents and injuries would cause a serious and negative impact on construction.  The project mantra was 'safety over productivity' and it was communicated, monitored and enforced from the top down, from start to finish.  EMCOR supplemented monthly project wide safety meetings with weekly safety meetings between management, field leaders and subcontractors.  We also required pre-task planning, job hazard analysis and environmental analysis be conducted on a daily basis, then used the plans and analyses to conduct a daily 'tool box talk', to review the scheduled activities, responsibilities and the associated safety and environmental risks with every member of the affected crew and subcontractors.  The daily tool box talk also allowed for questions and discussion between field personnel, supervision and other trades, mitigating potential misunderstandings as to what would take place and how it would be accomplished.

T-REX at Rest

In November 2006, T-REX was completed.  After 5 years of daytime realignments and nighttime closures; through wind, rain, snow and sunshine, T-REX is finally at rest.