Following a speed study of I-84 in the urbanized parts of the Treasure Valley, the Idaho Transportation Department (ITD) is reducing the speed limit on the western side of Caldwell to 65 MPH.
The current speed limit on I-84 traveling west goes from 65 MPH to 80 MPH after the Notus/Parma Exit (Exit 26). Due to the high number of vehicles using Middleton Exit (Exit 25) both east- and westbound coupled with varying speeds of thru traffic and merging vehicles, the Department determined a speed reduction was warranted. The 65 MPH speed zone will now extend west of Exit 25. Crews will place new speed limit signs today.
“We observed significant variations in speeds, with entering traffic speeding up to merge with I-84 traffic, which was slowing for the speed limit change,” said ITD Traffic Technical Engineer Erika Bowen. “This resulted in a number of near misses between cars on the Interstate and those looking to enter. Given the high demand at the Middleton Exit, we believe the change will improve the driving conditions in this area.”
ITD routinely studies sections of the State Highways System to ensure the safety, mobility, and economic opportunity of the traveling public is best served. Staff looks at the pavement condition, crash history, geometry, signage, and observed driver behavior when considering changes to the highway.
Over the last five years, growth near the Middleton Exit has seen an increase of 5,000 vehicles per day added to this section of I-84. During the evening commute, congestion often occurs at Exit 25 causing backups on the westbound off-ramps. ITD is looking at solutions for this separate situation to improve the efficiency of the interchange.