Signs that previously limited travel to 55 miles per hour on the long grade into Lewiston were replaced, reflecting an Idaho Transportation Department decision to increase the speed limit to 60 mph to improve safety and traffic flow.
The decision to change the speed limit on the grade was based on a recent ITD traffic study that indicated approximately 85% of motorists on that segment of U.S. 95 already travel at 60 mph. According to research, setting a speed limit according to that 85th percentile produces the fewest crashes.
The new speed limit is effective from the junction of U.S. 95 and Idaho 195 north of Lewiston (near milepost 318) to the bottom of the grade north Lewiston city limit (milepost 311).
Northbound, uphill traffic on the six-mile grade can continue to travel at the posted speed of 65 mph.
ITD encourages motorists to drive safely on their descent into Lewiston.The Idaho Transportation Department is responsible for all highways on the State Highway System – interstates, state highways and U.S. routes. All other roads are under the jurisdiction of the local, city or county entity.