I notice that the entrance/exit to the express lanes are “protected” (when you’re not supposed to enter) by a fence that’s strung across the lanes and there are some mechanical “arms” that deploy into the lanes.
My question is how do they deploy the system? I presume that cars will try to enter the express lanes as long as they can, so having the arms just pop out would potentially damage someone’s car. Likewise, it seems like it would be dangerous to have a guy drive his car into the “intersection,” stop and haul the fence across manually.
For about a minute before the arms and gates are deployed, they flash a sign (which is on the median and which just appears to be a black box during the rest of the day) stating that the gates will be closing. Then, the gates start closing very slowly. As far as I know, this process has never resulted in an accident. In addition, I believe they have a camera system to check that the lanes are empty before opening the lanes in the reverse direction.
You should also know that the express lanes are only reversible on the Kennedy. The Dan Ryan has full-time express lanes in each direction.