Completed

Updated October 2, 2025
Douglas County’s portion of the West Frontage Road Relocation Project has been completed. This significant infrastructure project is a portion of the overall Crystal Valley Parkway Interchange Project aimed at improving access and safety in the southern region of Castle Rock to residents and commuters. Crews will continue to be in the area to complete final finishing work, such as seeding. No traffic impacts to the public are expected to be minimal but please continue to watch for crews, drive posted speeds and never drive distracted.
The section of Dawson Trails Boulevard north of Tomah Road is currently open to local traffic only. Thank you for your patience during construction!
The West Frontage Road Relocation (Dawson Trails Boulevard) is part of a series of projects that will improve access and safety at the southern end of Castle Rock. Construction started on Sept. 9, 2024. The estimated 18-month road closure allowed for crews to safely build the new interchange and relocate this portion of the West Frontage Road to its new permanent location, west of the BNSF Railway tracks.
To accommodate construction of the new southbound I-25 on- and off-ramps at Crystal Valley Parkway, crews must relocate the current West Frontage Road that is east of the BNSF railroad tracks to the west side of the BNSF railroad tracks. The new road is now called Dawson Trails Boulevard.
This project, which will connect with the future Crystal Valley interchange, will enhance the roadway network, eliminate unnecessary railroad crossings, and provide a new west connection between Crystal Valley and Tomah Road interchanges.
Douglas County and the Town of Castle Rock have partnered to construct Dawson Trails Boulevard. Construction of Dawson Trails Boulevard will be split into two segments with one section being constructed by Douglas County:
Now that the improvements to the southern section of Dawson Trails Boulevard are completed, it will provide: