I've always wondered about the driver in the far left lane as I used the on ramp to enter a freeway. Would they change lanes to the right while I was trying to join the flow of fast moving traffic by moving into the same lane from the left? Not everyone bothers to signal their lane changes and having to move out of the lane before it ends adds to my complications.
A solution that I like is in use in the province of Quebec. The leftmost lane on the autoroute is marked with a combination broken and solid white line for the length of the on ramp. The solid line on the left side of the broken line prevents drivers in the fast lane from moving to the right but still allows drivers in the slow lane to move over and make room if they wish to do so.
The system works when drivers follow the rules, removing one complication from the equation of joining the traffic flow for the merging driver.
Of course, a defensive driver would consider the possibility and scan for those who don't follow the rules but the job could be made simpler through the use of a small amount of white paint. This would not be a significant expense in comparison to other highway improvements aimed at reducing conflict and collisions. It would also be simple to implement in the course of repainting the lines each year.
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