I-25 North Reconstruction Berthoud to Johnstown—Colorado Department of Transportation, Region 4

Muller serves as prime consultant for this multi-disciplined project team to provide preliminary and final design for an 11.2-mile segment of I-25 north of Denver from Berthoud (SH 66) to Johnstown (SH 402).

Muller’s work on the $500 million project started in 2012 with development of traffic demand models for using managed lanes in the corridor from SH 7 to Fort Collins. Following that, Muller completed the preliminary design for the entire SH 66 to SH 402 corridor segment. During the preliminary design phase, Muller structural engineers prepared structure selection reports for 22 bridges. To provide an interim remedy to mitigate rear-end accidents from mile post 246 to milepost 250, Muller prepared an early action breakout project for 4 miles of interim safety improvement to be implemented prior to the ultimate improvements. This required widening the south bound lanes and bridge over Valley Road. The project design was completed in four months, with the climbing lane and bridge widening completed in early 2017.

An additional breakout project was for a new bridge over the Little Thompson River for one of the future interchange ramps at the I-25 and SH 56 Interchange. Muller led a value engineering study during the preliminary design phase of the corridor to develop cost-effective and efficient improvements for the 11.2-mile corridor.

Final design was completed under a CM/GC delivery process, for the remainder of the project in two segments. Segment 5 was 6.1 miles long from SH 66 to SH 56 and includes 8 bridges, a parallel frontage road (some may be devolved), 1 interchange, 10 intersections, and ITS improvements (including managed lanes). Segment 6 was 5.1 miles long and included 13 bridges, a parallel frontage road, 3 interchanges (1 diverging diamond with signalization, 1 with I-25 flipped from under to over), 5 intersections, 2 roundabouts, and a park and ride facility. Muller’s 90% plans for Segment 6 include more than 1,500 plan sheets and more than 300 pages of specifications.