I-25 South Gap: Monument to Castle Rock

New Gap Logo.png

The 18-mile South Gap project is split into three geographic sections – north, middle and south. Construction began on the northern section, between Plum Creek Parkway and Sky View Lane/Tomah Road, in September 2018. In February 2019, crews began construction on the southern section of the project, between Greenland Road and Monument. In Summer 2019, construction began on the middle section of the project, between Sky View Lane/Tomah Road and Greenland Road. All 18-miles are currently under construction.

Speed Limit is Maximum of 60 mph

REMINDER: Drivers along the 18-mile corridor will notice electronic speed limit signs. These signs replaced existing speed limit signs and display a reduced speed of a maximum 60 mph. 

In addition to displaying a reduced speed limit, these electronic signs will allow the project to change the speed limits in real-time - based on weather conditions, crashes or construction-related impacts. These speeds will be enforceable, so please remember to watch for posted speed limits and pay attention through the construction zone.

Spruce Mountain Road Bridge Demolition

Project Facts

The Gap is an 18-mile stretch of Interstate 25 from south of Castle Rock to Monument. It is the only four-lane section of I-25, connecting Colorado's two largest cities, Denver and Colorado Springs. Over the years, congestion, crashes and delays have grown due to population growth and more people using the road.

Efforts to improve these conditions are underway.

  • Cost: $350 million, with contributions from Douglas and El Paso counties, Pikes Peak Rural Transportation Authority and a federal INFRA grant
  • Contractor: Kraemer North America
  • Timeline:  Project completion is slated for 2022
  • Location: 18 miles in both directions of I-25, south of Castle Rock to Monument, in Douglas and El Paso counties

Construction underway 

Crews are actively improving an 18-mile stretch of Interstate 25 known as "The Gap," which starts south of Castle Rock and continues to Monument. 

Project benefits

 Safety: Crews will widen shoulders outside and inside the travel lanes for vehicle pull-off and emergency response. This improvement will also help with drainage.

 Driver choice: After crews add an Express Lane in each direction of I-25, drivers will have the choice to use the Express Lane for a reliable trip in exchange for a toll, or to use one of the two general-purpose lanes for free. Carpoolers (vehicles with three or more people) and motorcyclists can ride the Express Lanes for free.

 Wildlife safety: Crews will construct four new wildlife crossings and install deer fencing.

 Improved pavement: Crews will add a new overlay to the existing pavement for a smoother ride.

 Improved infrastructure: Crews will reconstruct four bridges and extend ramps.

 Improved truck access: Crews will add truck climbing lanes near Monument Hill and the Greenland exit.

 Advanced technology: Crews will modernize communications and power along the corridor to enable advanced technology.

Gap Map Horizontal view of Stretch.

Driver Impacts

Construction, by nature, will always impact those who use the road. Two lanes of traffic will be maintained in each direction of I-25 during the day.

Still, drivers should expect slower speed limits (60 mph), narrower lanes, increased volume, nighttime lane closures, and construction trucks entering and exiting the interstate throughout the corridor.

Construction crews will be working around-the-clock and sometimes on weekends to deliver these improvements on-time, on-budget and with as little impact as possible.

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