The Colorado DOT (CDOT) recently announced that reconstruction has begun on the County Line Road bridge over I-25, one of five structures to be replaced as part of the 18-mile I-25 South Gap project between Monument and Castle Rock.
In partnership with contractor Kraemer North America, the County Line Road bridge will be doubled in size to accommodate one through-lane, one turn-lane in each direction, and wider shoulders on each side. The bridge will be built in two separate phases. First, crews will build the outside lanes of the bridge. Once those lanes are built, they will demolish the existing bridge structure and reconstruct the bridge to connect it to the new outside lanes.
According to CDOT, improvements to the County Line Road bridge will fix sight distance issues on the ramps, upgrade aging infrastructure (built in 1964) and improve County Line ramp acceleration and deceleration lanes.
The I-25 South Gap project will achieve other major milestones this year. In addition to the completion of the County Line Road bridge in fall 2021, crews will finish construction of the Upper Lake Gulch Road and Plum Creek bridges near Larkspur. All full-span wildlife underpasses will be complete by the end of 2021. This summer, crews will focus on paving the remaining 13 miles of the project between Sky View Lane/Tomah Road and Monument. Major highway construction of the northern 5 miles of the project between Plum Creek Parkway and Sky View Lane/Tomah Road is complete, with the Express Lanes in this section opening with the rest of the project in 2022.
The original project cost was $350 million. Additional funding was needed to cover the construction of the County Line Road bridge, southbound I-25 Monument Hill truck climbing lane, southbound I-25 truck chain-up station, and to address the issue of unsuitable soil found following the start of construction. In 2019, funding became available for these improvements. The current total budget is $419 million. The project remains on budget, but the overall project cost increased when additional benefits were included, according to CDOT.
Major bridge construction of the County Line Road bridge is expected to be complete by the end of 2021. Construction of the 18-mile I-25 South Gap project, including the surrounding County Line Road bridge area, remains on-time for completion in November 2022.
SOURCE: Colorado DOT