Frontage Roads

Frontage Road Closures Ongoing

As part of the I-25 South Gap project, crews are replacing major drainage pipes in the northern section of the project, between Castle Rock and Larkspur. These drainage pipes run underneath I-25 and both the East and West Frontage Roads.

The next closure is expected in early 2020. Follow the I-25 South Gap Facebook page for updates.

About the Work

While crews will complete as much of the work as possible behind construction barrier, some closures of the frontage roads will be necessary to safely install these large pipes.

There are 11 total drainage crossings on the west side, and 23 on the east side – some pipes are as large as 48 inches and buried as deep as 16 feet. Safely installing these drainage crossings will require one-way flagging and a series of 10 closures over the next year.

About the Closures

  • 10 closures are expected intermittently over the next year, starting in late September 2019 (see map below).
  • Each could last up to eight days.
  • Closures will happen one at a time.
  • Detours will take drivers around the closures via the opposite frontage road or I-25.
  • Crews have coordinated the closure blocks so driveways are not impacted and access for schools and businesses is maintained.

This web page will be updated prior to planned closures, or sign up for email updates by emailing [email protected]

Safety First

  • The speed limit along frontage roads has been reduced to 45 mph. During flagging operations, it will be 40 mph.
  • Please pay attention.
  • If you are not local traffic, please stay the course on I-25 Remember: both frontage roads are striped with double-yellow lines, so passing is legally prohibited.

Keep in Touch with the Project

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