Office of Operations
photos of traffic merging onto congested highway, congestion in snowstorm, variable message sign, cargo, variable speed limit sign in a work zone, and a freeway at night
21st Century Operations Using 21st Century Technologies

Traffic Bottlenecks

Combating Bottlenecks


Dualizing a former one-lane off ramp will remove backups onto the mainline, and will help address a high crash section of highway that suffers from poor weaving in advance of the off-ramp.

A high concentration of primarily rear end and sideswipe-passing crashes was occurring on WB I-480 between the I-71 SB on-ramp and the Grayton Road off-ramp, a distance of approximately 3000 feet. Much of the problem was attributed to the long queues on the Grayton Road off-ramp due to heavy LT volumes, in one lane, backing up onto the mainline, and exasperating the weaving conditions approaching the off-ramp. The proposed solution was to make off-ramp modifications that would dualize the left turns. Even with this modification, the now three-lane off-ramp was still 150' short of desired queue storage based on 20-year modeling. The $600K project would have to be tripled in order to add the short length, due to need to acquire expensive right of way and essentially relocate the off-ramp intersection. It was agreed that the public would get a 14+ year benefit from the "interim" upgrade and the project went forth. The location will be monitored to determine if the future, modeled, constraints come to bear.