SEMA Construction's $562M project on I-25 in Colorado Springs aims to improve traffic flow and safety with new lanes, bridge reconstruction, and ITS upgrades. Completion expected by August 2026, impacting 150,000 daily commuters and local businesses.
Colorado DOT photo
A Cat 335F L hydraulic excavator is a key part of the equipment needed for the Interstate 25 project to add acceleration and deceleration lanes.
In late October 2023, SEMA Construction started work on the Colorado Department of Transportation's (CDOT) $562 million Interstate 25 Acceleration/Deceleration Lanes from Fillmore Street to Garden of the Gods Road project in Colorado Springs to improve traffic flow and safety on the busy highway.
The El Paso County project adds acceleration and deceleration lanes and replaces an aging bridge on I-25 over Ellston Street. The anticipated completion date is late August 2026.
"The growth of the community and business expansion has necessitated the initiation of the improvement project," according to the project web page. A technical analysis for the project was conducted in mid-2021, and final design work occurred from late 2021 through summer 2023.
Continuous acceleration and deceleration lanes will be added to both the northbound and southbound directions of I-25, spanning from Garden of the Gods Road to Fillmore Street.
The goal of the auxiliary lanes is to even out traffic flow and assist drivers in merging into and exiting traffic efficiently. To further enhance road safety, the roadway is being resurfaced and adjustments are being implemented to address drainage concerns.
The bridge on I-25 over Ellston Street will be reconstructed and widened, along with bridge deck repairs on the Garden of the Gods overpass structure.
Upgrades to the intelligent transportation system (ITS) infrastructure — fiber optics and ramp meter station — "will help with the flow of traffic to monitor, trigger and time vehicle release with automatic vehicle and queue detection to mitigate any traffic backups by adjusting meter timing," according to the web page.
"Auxiliary lanes help balance traffic and facilitate smoother traffic flow as drivers merge and exit," said Shane Ferguson, regional transportation director of CDOT's Region 2 Southeast Colorado District. "Resurfacing the roadway will create a smoother driving surface for motorists. To help with drainage issues on the roadway, curve cross-slope corrections will be made."
The average daily traffic count is 150,000, including local commuters, regional travelers and interstate commerce.
"The Pikes Peak Region's growth has had a significant impact on congestion, crashes and delays," said Amber Shipley, a CDOT communications manager. "Crash history in this area includes sideswipes, fixed objects and wildlife."
For the reconstruction of the Ellston Street bridge, concrete beams were installed. Once in place, the rebar was added to prepare for the concrete pours.
During the bridge's initial construction phase, crews had a large workspace, which allowed them to bring equipment in and out and store construction materials with ease. Preparing the site involved large-scale earthwork and excavation operations for the new lanes and the bridge construction.
"The bridge will meet today's standards of durability and structural integrity with a lifespan of 70-75 years," CDOT Region 2 North Program Resident Engineer Yun Su Han said.
The road work has crews operating in the Fillmore Street area next to I-25, with slopes where they are driving piles and excavating sites for new lanes.
Temporary lanes and platforms were created so that heavy equipment could operate safely. The equipment onsite includes a large Volvo excavator, a motor grader, a large pile driver, a bulldozer, a telehandler and other support vehicles.
Pile driving also occurred at Ellston Street, adjacent to an overpass.
Mechanically stabilized earth walls approximately 20 ft. tall were installed along the northbound side of I-25 next to the new lane. Large excavators, including a Cat model, aided in the site prep.
Prefabricated concrete panels are being attached to the previously driven piles that were driven. Dozers helped to prepare the sites for the installation of the panels.
Grove wheeled cranes help to lift the panels. Equipment operators had plenty of space to maneuver on the ground where new lanes were set to be paved, so the space also was used to store panels delivered to the site.
The hot mix asphalt resurfacing has an approximately 15- to 25-year lifespan with regular maintenance. This roadway is susceptible to snow/freeze/thaw effects and significant traffic/speed, which can decrease the lifespan.
The work impacts traffic, with permanent and temporary lane closures planned mostly during nighttime hours with low traffic.
"Colorado Springs has an avid bicycling community that uses the Sinton Trail which runs under I-25 at Ellston Street," Shipley said. "Limited access during peak construction times and closures with a significant detour route during major construction of the bridge has been a challenge. Our project communications team has a liaison working directly with the bicycling community."
This is a near 24/7 project, with daytime work hours from 7 a.m. to 7 p.m., Monday through Sunday and overnight work shifts from 10 p.m. to 5 a.m., Monday through Friday.
Typical days have a fair amount of SEMA Construction and subcontractor personnel on-site.
Based in Centennial, Colo., SEMA Construction buys and rents equipment from local and regional dealerships.
(All photos courtesy of the Colorado Department of Transportation.)
Irwin Rapoport
A journalist who started his career at a weekly community newspaper, Irwin Rapoport has written about construction and architecture for more than 15 years, as well as a variety of other subjects, such as recycling, environmental issues, business supply chains, property development, pulp and paper, agriculture, solar power and energy, and education. Getting the story right and illustrating the hard work and professionalism that goes into completing road, bridge, and building projects is important to him. A key element of his construction articles is to provide readers with an opportunity to see how general contractors and departments of transportation complete their projects and address challenges so that lessons learned can be shared with a wider audience.
Rapoport has a BA in History and a Minor in Political Science from Concordia University. His hobbies include hiking, birding, cycling, reading, going to concerts and plays, hanging out with friends and family, and architecture. He is keen to one day write an MA thesis on military and economic planning by the Great Powers prior to the start of the First World War.
Read more from Irwin Rapoport here.
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