Idaho to deploy variable speed limit signs in I-84 work zone

Aug. 11, 2021

Crews will be able to change the speed limit on digital signs to actively manage conditions in the work zone

The Idaho Transportation Department (ITD) this week will deploy variable speed limit signs within the I-84 construction zone in Canyon County in order to enhance safety for workers and travelers.

Currently, speeds in the work zone are often reduced to 55 mph or 45 mph depending on construction activities, ITD said in a press release. When construction crews are not in the work zone or when safety barricades are in place, the speed limits may be raised to 65 mph, in order to promote mobility without sacrificing safety on the interstate.

Upon approval, crews can change the speed limit on these digital signs to actively manage conditions in the work zone. A flashing beacon will notify drivers in advance when speed limits are reduced from 65 mph.

“This project is complex and requires several phases of work,” ITD Design Construction Engineer Shawna King said in a statement. “There are numerous crews completing specialized work and the number and location of crews will vary day to day. Implementing the variable speed limits will allow us to keep crews and motorists safe while work is being done, then bring speeds back to normal when it is safe to do so.”

The work on I-84 between Franklin Road (Exit 29) and Karcher Road (Exit 33) will construct an additional third travel lane in each direction. Traffic is currently diverted to the outside lanes while crews construct the inside portion of the future roadway. When that phase of work is complete, traffic will be diverted onto the newly-constructed inside lanes and work will begin on constructing the outside lanes. Crews will also replace numerous bridge structures along the 5-mile corridor.

ITD says the use of variable speed limits tends to improve driver compliance with posted speed limits, which in turn can reduce crashes and improve safety for road crews and the motoring public. The signs will be removed when construction is complete in summer 2023.


SOURCE: Idaho Transportation Department