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C470

History

CDOT is expanding the travel lanes along the South corridor of C470 to add toll lanes to the existing interstate from the I-25 interchange to Wadsworth Blvd.  Flatiron/AECOM joint venture was the general contractor on the project.  This is a multiyear project that began in 2016 and is scheduled to be completed in 2019.  BTrenchless was a subcontractor on the project, tasked to complete the TBM's and Sliplines of the new RCP storm sewer system. 

Challenges

The TBM's ranged in size from 42" RCP to 72" RCP.  The drives ranged in length from 324 LF to 387 LF.  The total length of the five drives was 1695 LF.  During one of the drives, we encountered two abandoned waterlines under the interstate.  One of which was a 48" steel waterline and the other was a 12" AC waterline that were in direct conflict with the TBM and had to be removed to continue the drive.  The sliplines ranged in size from 36" RCP to 72" RCP.  The pulls ranged in length from 267LF to 434 LF.  The total length of the pulls was 1378 LF.  The biggest challenge during the sliplines was dealing with the deteriorated Corrugated Metal Pipe (CMP), while trying to pull the RCP through them. 

Solutions

The diversity of this project allowed BTrenchless to utilize two different types of trenchless technology and capitalize on the vast resources of both people and equipment to successfully complete this complex and high profile project, all while maintaining traffic flow along the C470 corridor.