American Fork, Utah (Dec. 15, 2012) — The Utah Department of Transportation announced today the Utah County I-15 Corridor Expansion (I-15 CORE) is now complete. Construction on the project was finished in an unprecedented 35 months, making it the fastest billion-dollar public highway project ever built in the United States.

“We worked closely with Provo River Constructors to employ innovation at an unprecedented level to ensure we delivered this project in record breaking time and under budget,” said Todd Jensen, I-15 CORE project director. “We used the same innovative techniques to minimize the usual delays associated with construction projects.

“We want to thank the public and local businesses for their cooperation during construction,” Jensen said. “We couldn’t have completed this project as quickly or as effectively without their help.”

I-15 CORE reconstructed 24 miles of freeway from Lehi to Spanish Fork. The project widened the freeway by two lanes in each direction; replaced the original asphalt with new 40-year concrete pavement; extended the Express Lane from Lehi Main Street to Spanish Fork; and rebuilt or replaced 63 bridges and 10 freeway interchanges.

The project came in $260 million under budget.

One of the most significant achievements of the I-15 CORE project was the innovative methods employed to keep traffic moving throughout construction. Work activities were scheduled around the clock in order to meet the aggressive schedule, but the majority of lane and exit closures – more than 90 percent – were scheduled during overnight hours to reduce traffic delays. Innovative traffic patterns including lane shifts and splits were used to keep as many lanes open as possible while maintaining safety for construction workers and allowing the work to continue.

During construction, the I-15 CORE project achieved several notable milestones:

  • Moved the Sam White Bridge — the longest two-span bridge to be moved by self-propelled modular transporters (SPMTs) in the Western Hemisphere — into place over I-15 in one night
  • Constructed a new continuous flow intersection (CFI) — the first of its kind in Utah County — at University Parkway and Sandhill Road to reduce congestion at one of the busiest intersections in the county
  • Constructed a new diverging diamond interchange (DDI) at 500 East in American Fork — the third DDI completed in Utah County
  • Completed more than 90 percent of I-15 closures and restrictions during overnight hours to reduce inconvenience to the public
  • Implemented lane splits to keep existing travel lanes open as much as possible while paving continued in the middle of the freeway
  • Installed advanced traffic management system (ATMS) devices including 93 sensors, 36 cameras, 22 ramp meters and four permanent variable message signs to help UDOT engineers monitor traffic, respond to incidents and ensure the transportation system functions as efficiently as possible to keep traffic moving.

I-15 CORE was built by Provo River Constructors (PRC), a consortium headed by Fluor Corporation, with Ames Construction Company, Inc., Ralph L. Wadsworth Construction Company, Inc. and Wadsworth Brothers Construction Company, Inc. The consortium includes more than 30 subcontractors.