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I-25 South Gap Project: Monument To Castle Rock

Transportation

Closing the Gap on Colorado's busiest interstate.

For years, the 18-mile stretch of I-25 between Monument and Castle Rock was the only four-lane section left between Denver and Colorado Springs — a congested, crash-prone bottleneck known simply as “the Gap.” CDOT’s $350 million I-25 South Gap Project, delivered through the CM/GC method with Kraemer North America, widened the interstate to three lanes in each direction with a new express lane, reconstructed five bridges, extended ramps, built five wildlife crossings to reduce animal-vehicle collisions, and placed a new pavement overlay along the full length of the corridor. Construction ran from 2018 through 2022.

Partnering with Rocksol Consulting Group, Vivid Engineering provided owner’s acceptance inspection and materials testing for CDOT on the project. Vivid inspectors and technicians covered drainage features, retaining walls, bridge structures — including caisson and bedrock observations at the new bridge foundations — and pavements, along with test pits and DCP testing to confirm subgrade conditions, verifying that the work met CDOT’s standards on one of the most heavily traveled corridors in the state.

Project Details

  • Client

    Rocksol Consulting Group

  • Location

    I-25, Monument to Castle Rock – Douglas & El Paso Counties, CO

  • Project Value

    $350 million

  • Timeline

    Construction 2018 – 2022

  • Sector

    Transportation

  • Services

    Construction Inspection & Testing

Project Location

I-25, Monument to Castle Rock, CO (18 miles)

Nearest City: Monument and Castle Rock

County: El Paso and Douglas

State: Colorado

Highway route

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