CDOT to begin work on improving the Greenland Road interchange as part of the I-25 South Gap project

July 17, 2019 - Work requires a new traffic pattern, significant safety measures in place on corridor  

As part of the Interstate 25 South Gap project to improve safety and travel reliability, crews are beginning work to rebuild the Greenland Road interchange from a single-lane box culvert to a full two-lane underpass and build a wildlife crossing north of Greenland Road.  These improvements are part of CDOT’s Whole System-Whole Safety program. 

This construction will require a new traffic pattern called a crossover on I-25 at the Greenland Road interchange so crews can safely do the work.  Drivers will still have ramp access, but the northbound ramps will shift a quarter-mile to the south. Two lanes will remain open in each direction on I-25 during the daytime and high-peak travel periods. 

In order to safely set up the crossover, crews will need one overnight single-lane closure of northbound I-25 at the Greenland Road Interchange on Wednesday, July 17, 6 p.m. to 6 a.m.   Motorists should expect delays between 6 p.m. and 9 p.m.  *See graphic at bottom of release.

Motorists will drive the completed configuration starting on Thursday, July 18. All construction schedules are weather-dependent. 

When driving the crossover, motorists should slow down and exercise caution.

Safety Tips for Driving the Crossover

Drivers can expect a significant grade change in the area, so please pay extra attention when driving in this area. Stay the course, but plan a little extra time to get to your destination. Slow down, stay alert and watch for crews.

The following tips are to help you stay safe while traveling through maintenance and construction work zones.

  • Do not speed in work zones; obey the posted speed limits.

  • Stay Alert! Expect the unexpected.

  • Watch for workers; drive with caution.

  • Don't change lanes unnecessarily.

  • Avoid using mobile devices such as phones while driving in work zones.

  • Turn on headlights so that workers and other drivers can see you.

  • Be especially alert at night while driving in work zones.

  • Expect delays, especially during peak travel times.

  • Allow ample space between you and the car in front of you.

  • Anticipate lane shifts, and merge when directed to do so.

  • Be Patient!

Project Contact Information 

Project Hotline: 720-745-5435


Sign up for email updates: [email protected]

Text alerts: Text I25GAP to 21000

Project Facebook Page:

The following safety measures have been implemented on the project:

  • Reduced speed limit to 60 mph, and installed Portable Variable Speed Limit Signs. These boards allow the project to adjust the speed limits in real-time based on weather conditions, crashes, or construction-related impacts. With this technology, crews can slow down traffic ahead of a crash, incident or weather impact, possibly reducing the likelihood of secondary crashes. 

  • Increased law enforcement by the Colorado State Patrol to cover the project seven days a week, contingent upon CSP resources.

  • Ensure adequate first responder access by providing access breaks in the barrier where possible.  

  • Provide shoulder pull-off locations for emergencies.  

  • Limit lane closures to off-peak travel periods at night unless emergency situations warrant a lane closure such as road damage repairs or other emergency situations.

  • No detouring traffic to alternate routes, such as Colorado Highway 83 or Colorado Highway 105. 

  • Dedicated multiple courtesy patrol vehicles to the project, which has helped greatly to get disabled vehicles off the road and traffic moving.

  • Monitor traffic through a project operations center that uses cameras, signs and vehicle detection devices to help with incident management. 

  • Deployed numerous Smart Work Zone systems and devices that warn motorists of backed up traffic, trucks entering and exiting the work zone and other incidents and activities.  

  • Stage equipment by the contractor prior to large snow events to assist with snow operations and response issues.

  • Hold bi-weekly meetings with emergency response agency partners to coordinate efforts on project operations and work zone safety. 

  • Implemented significant safety improvements on the frontage roads from Larkspur to Castle Rock.

  • Implemented extensive public relations efforts including, text alerts, social media, special media briefing events, paid advertising campaigns, public meetings, weekly e-blasts to stakeholders, regular meetings with stakeholders and elected officials, coordinating seamlessly between two counties.

  • Added Bustang routes and ride-sharing program from Colorado Springs to the Denver Tech Center to give motorists other travel options during construction.

  • Provide extra lane for the Renaissance Festival to help alleviate traffic congestion during this 8-week event. 

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 also includes shoulder widening, rebuilding bridges, new wildlife crossings, resurfacing with new pavement and modernizing technology. Project completion will occur in 2022.

Travel options to improve commutes are available during construction. Some of the services include a new Bustang route from Colorado Springs to the Denver Tech Center. CDOT is partnering with the Denver Regional Council of Governments' Way to Go program to provide more commuting options, such as incentives to vanpool and carpool. Visit to learn more.


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. 

*Graphic of new traffic pattern: I-25 crossover at Greenland Road interchange
I-25 Gap Traffic Pattern 7-18-19.png