Rethink those roundabouts
Your piece on roundabouts caught my interest. [News, "Going in circles," January 30, 2003] (http://www.readthehook.com/93012/news-going-circles-roundabouts-come-rou...). As a UK citizen, I am very familiar with traffic roundabouts, as we have thousands of them in Europe. When I first arrived here in Charlottesville, I thought that you were missing out on a sensible traffic control device at intersections.
Now, however, I think that your light control system may have advantages, especially with the filter "right on red"– something we are not allowed to do in the UK.
Roundabouts are a big disadvantage when there is a heavy traffic flow along one of the roads. You can wait for ages before a safe gap opens in the traffic to allow you to enter the roundabout. The line waiting to enter can get long enough to block intersections before the roundabout.
Roundabouts also send a continual flow of traffic leading away from them which can make it difficult to enter the highway from a side road, especially turning left.
A light-controlled intersection does allow traffic flow to be regulated and leaves blocks of free space, giving vehicles a chance to join the main highway. Leaving a roundabout requires careful positioning, and often you have vehicles on the right blocking a turn. Getting on and off a busy roundabout certainly slows traffic, but it's hazardous, and usually the bully wins.
Roundabouts take up a lot of space, especially if semi trucks are to negotiate them. It's essential that drivers can see over them to be prepared for the vehicles coming round. They must not become a landscaping opportunity. Charlottesville does seem to have a lot of thoughtless decorative planting which grows up to obscure useful signs and sight lines.
I would agree that roundabouts are good on minor routes and in residential areas, but I would advise the planners to think carefully about them on major routes and remember to look beyond the immediate intersection. One of the best solutions is light controlled roundabouts. These are probably the safest method of negotiating an intersection, but not the fastest.