08-13-2008, 06:29 AM
>>>Just widening the road does very little to improve flow at the major intersections, as you have 2 lanes to jump across now instead of 1.
It doesn't help with left turns, but it helps with turning right. I've experienced many times that if you're waiting to make a right turn it's easier to get out if there are two lanes my direction.
For left turns, there should be signals at crucial points, and a center lane to turn into.
Having two lanes each way means that when the light turns red the traffic waiting is spread out laterally and doesn't back up as far.
Roundabouts may be more efficient when you test flow with the assumption that all drivers know how to drive the intersection, but American drivers get confused by roundabouts as they are not the norm, and confusion is not a good thing.
It doesn't help with left turns, but it helps with turning right. I've experienced many times that if you're waiting to make a right turn it's easier to get out if there are two lanes my direction.
For left turns, there should be signals at crucial points, and a center lane to turn into.
Having two lanes each way means that when the light turns red the traffic waiting is spread out laterally and doesn't back up as far.
Roundabouts may be more efficient when you test flow with the assumption that all drivers know how to drive the intersection, but American drivers get confused by roundabouts as they are not the norm, and confusion is not a good thing.