Crews wrapping up final stage of I-84 corridor construction

Months earlier than originally expected, all lanes are open on Interstate 84 between the Franklin and Garrity interchanges in Nampa as work wraps up on the construction project that widened two miles of interstate.

Work began in July 2010, and is reaching completion nearly three months ahead of schedule.

Minor construction activity continues as crews complete roadside sign installation, cleanup tasks and utility work along the shoulder. Short-term lane reductions might be required.

In these instances, the speed limit will be reduced to 55 mph as a safety precaution for motorists and for crews working next to moving traffic.

This spring, crews will return to paint final lane markings on I-84 and reconfigure the traffic signal and lane markings at the westbound Franklin off-ramp.

The project included:

  • Widening two miles of I-84 from two to three lanes in both directions;
  • Adding an auxiliary lane for eastbound traffic; the auxiliary lane allows motorists to enter I-84 at the Franklin Boulevard on-ramp, remain in the same lane, and exit at Garrity without ever merging with interstate through traffic;
  • Constructing two new bridges to accommodate interstate widening: one over the Phyllis Canal and the other over the Union Pacific Railroad; and
  • Reconfiguring on- and off-ramps to improve driver safety. Longer ramps and more gradual alignments promote safer merges with interstate traffic when exiting from the interstate.

ITD worked closely with businesses along the corridor, providing advance notification and detour maps, and scheduling ramp closures to avoid peak traffic times and high-traffic events such as those scheduled at the Idaho Center.

The widening project improves the highway surface, adds capacity and will safely accommodate projected traffic volumes through 2032, when the area is expected to see 40 percent more traffic.

I-84 provides a vital link between Canyon and Ada counties for both commuters and freight, and carries the highest volume of traffic in the region. The corridor from west of Caldwell to east of Meridian experienced pressure over the last decade from rapid growth west of Boise.

The widening project is one of several interstate improvement projects in an 18-mile stretch of I-84 funded by the GARVEE Transportation Program. The program uses proceeds from Grant Anticipation Revenue Vehicle (GARVEE) bonds to accelerate highway improvements in key Idaho corridors.

Concrete Placing Company, of Boise, is the contractor on this $22.2 million project.

Published 2-10-2012