I-25 South Gap Marks One Year of Construction

September 4, 2019 - Denver Metro Area/Southeastern Colorado

DOUGLAS/EL PASO COUNTIES — Today is the first year anniversary of the Colorado Department of Transportation’s Interstate 25 South Gap project, designed and constructed to improve safety and travel reliability between Monument and Castle Rock.

As part of its Whole System – Whole Safety program, CDOT is adding a new Express Lane in each direction, widening shoulders, building four new wildlife crossings, reconstructing four aging bridges and improving the pavement throughout the 18-mile segment, the longest work zone in Colorado.

As part of marking the project’s first year of construction, CDOT is adding funds replace the County Line Road bridge between El Paso and Douglas counties and to add a truck climbing lane in the southbound direction from Greenland Road to the Truck Weigh Station in Monument.

“At CDOT, our goal is to get everyone home safely,” said CDOT Executive Director Shoshana Lew. “Every day our crews are working hard to improve our infrastructure through massive construction projects. We are excited and proud to be recognizing this milestone on the I-25 South Gap project with additional funding for the climbing lane and for another bridge replacement.”

Milestones from Year One

From September 2018 to August 2019, crews have accomplished the following:

  • Along the entire 18 miles, crews have installed 10 of 12 total miles of new fiber optic line
  • Near Castle Rock, crews have installed more than three miles of permanent pavement
  • In excess of 60,000 tons of asphalt have been installed thus far (more than 800,000 tons of asphalt will be laid project-wide)
  • More than 16,000 linear feet of new pipe have been installed (nearly 45,500 linear feet will be installed)
  • At Greenland Road, crews have shifted traffic to demolish the outdated, single lane box culvert and rebuild the interchange into a two-lane underpass; drivers are now traveling on some permanent pavement in the area
  • Began constructing three wildlife crossings near Monument. Work has included girder sets, deck pours and earth retaining walls. Nearly 6,000 linear feet of bridge beam will be set in this area by fall
  • A sound wall is nearly complete along southbound I-25 near the Monument Truck Weigh Station
  • More than 163,300 linear feet of concrete barrier has been installed (crews will work behind more than 250,000 linear feet of concrete barrier when it is fully installed)

I25 MyWay – Better Commuting Options

The I-25 South Gap project has partnered with the Denver Regional Council of Governments to provide commuting options to those driving through the I-25 South Gap. People who have chosen to commute have helped reduce the drive-alone rate – which reduces congestion in the construction zone. Commuters have also improved overall air quality, saved money, reduced stress, and taken back their time when not behind the wheel thanks to the I25 MyWay program. For more information on commuting options, visit i25myway.org.

As of July 31, 2019:

  • 2,313 riders on new Bustang Denver Technological Center route (began Dec. 17, 2018)
  • 977 cars off the road in just 159 days since launch of Bustang DTC Line
  • 402 vanpool riders resulting in 341 cars off the road
  • 126 free roundtrips provided for use on the South Line to Union Station or the route to the DTC
  • 1,401 cars off the road every work day thanks to vanpools, Bustang and other commuting options through the I-25 South Gap

About the Project

CDOT is improving 18 miles of I-25 between Monument and Castle Rock by widening the highway from two to three lanes in each direction. The new lane will operate as an Express Lane, allowing motorists the choice of taking the Express Lane for a faster, more reliable travel time in exchange for a toll. Express Lanes will be free to vehicles with three or more people and motorcycles. All travelers will have the choice of taking the general-purpose lanes for free.


The $350 million project, scheduled for completion in 2022, also includes new and improved signing and striping, and modernizing technology.


Whole System - Whole Safety

To heighten safety awareness, CDOT recently announced its Whole System. Whole Safety initiative. This project takes a systematic statewide approach to safety combining the benefits of CDOT’s programs that address driving behaviors, our built environment and the organization's operations. The goal is to improve the safety of Colorado’s transportation network by reducing the rate and severity of crashes and improving safety conditions for those traveling by all transportation modes. The program has one simple mission - to get everyone home safely.



CDOT has approximately 3,000 employees located throughout Colorado, and manages more than 23,000 lane miles of highway and 3,429 bridges. CDOT also manages grant partnerships with a range of other agencies, including metropolitan planning organizations, local governments and airports. It also administers Bustang, the state-owned and operated interregional express service. Gov. Jared Polis has charged CDOT to further build on the state’s intermodal mobility options.