Traffic Impacts

For the week of Aug. 2


REMINDER – Text alerts: The I-25 South Gap project team is dedicated to keeping its stakeholders well-informed. If there is ever an emergency closure or important project update, don’t be the last to know! Sign up for text alerts today – text I25gap to 21000 – to receive important information directly to your cellphone. Remember – if you are driving, keep your hands off the phone and your eyes on the road. Drive safely! 

Remember: All construction schedules described below are weather-dependent and could change.

Monument Hill Frontage Road Closure Coming Soon

Crews plan to close a portion of the Monument Hill Frontage Road, east of mainline I-25, for about seven months. This closure was originally planned for the week of Aug. 9, but has shifted to mid-August due to rainy weather preventing critical paving operations in the area. This 1,100-foot closure is required as crews construct a wildlife underpass, replace drainage pipes, complete roadway construction and install a soundwall between northbound I-25 and the frontage road. The closure will be located between the Colorado Heights Campground access points.

As one of four wildlife crossings included in the project, this wildlife underpass will help reduce animal-vehicle collisions along the I-25 South Gap corridor, and the improved drainage will prevent flooding and soil erosion in this area. For more information on this closure, visit the Monument Hill Frontage Road Closure webpage.

Kraemer-SouthGap-DetourMap-Frontage Road Closure.jpg


* Remember: planned lane closures can be affected by weather. 


Description Time Frame Work Detour

Overnight single lane closures northbound and southbound I-25
between Plum Creek Parkway and Monument

Aug. 2-7
8 p.m. to 5 a.m.

Guardrail and pothole repairs, guardrail removal, grading, traffic shifts, striping operations, pavement work, paving operations, fiber testing, emergency pull-out sign placement and barrier work.

One lane open in each direction of I-25.
Stay the course!

Full closure of the southbound I-25 off-ramp to Upper Lake Gulch Road

Ongoing closure until further notice
(Began Oct. 25)

Bridge demo and rebuild.


To access northbound I-25 from Larkspur, motorists should use the Upper Lake Gulch Road on-ramp to northbound I-25.

To access Larkspur from southbound I-25, motorists should use the southbound I-25 off-ramp to Spruce Mountain Road.

Full closure of the Spruce Mountain Road on-ramp to northbound I-25

Ongoing closure through the fall
(Began in October 2019)

Bridge demolition and 

Access northbound I-25 from Upper Lake Gulch Road

Full closure of the southbound I-25 on- and off-ramps at Greenland Road for 45 days

Ongoing through mid-August

Reconstruct ramps, construct fills, install drainage and remove unsuitable material

Motorists will be detoured to County Line Road or Upper Lake Gulch Road.

Shoulder closures along northbound and southbound I-25 throughout the 18-mile project corridor.  

Aug. 3-7
8:30 a.m. to 4 p.m.

Earthwork and erosion control

One lane open in each direction of I-25. 
Stay the course!


Description Time Frame Work Detour
Single lane closures and flagging operations
along East and West Frontage Roads 
Plum Creek Parkway and Sky View Lane (Tomah Road)

Daytime Hours

Aug. 3-7
7 a.m. to 5 p.m.

Installation of fiber optic lines,
frontage road repairs and install
Watch for flaggers who will direct traffic.
Residential access will be maintained. 
Thank you for your patience!
Flaggers will be present at the Greenland Road and Upper Lake Gulch Road access to I-25

Aug. 3-8
6 a.m. to 6 p.m.

Bridge work Watch for flaggers who will direct traffic.
Residential access will be maintained. 

Project Offices in Castle Rock

A temporary construction office for CDOT and its contractor partner, Kraemer North America, is located near the intersection of Crystal Valley Parkway and the I-25 east Frontage Road. Please watch for vehicles entering and exiting the site throughout the duration of construction. Upon project completion, the area will be returned to its previous state; the asphalt will be removed and the area will be re-graded and seeded.

Safety for drivers and workers is our top priority during construction.

 Get project text alerts:
Text I25GAP to 21000.

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