When roundabouts don't work.
They are practically everywhere in Sydney. I remember them coming in in a big way a few decades ago.
The vast majority of them are little tiny things; small enough that busses go over them and people treat them as a variant of stop-sign intersections. One of the largest in Sydney, the five-ways at Miranda, was replaced with a traffic-light intersection a few years ago. The reason? Accident reduction.
But there are places where they are counter-productive. That's where two legs have much more traffic than the other two. Near where my parents live, we had an intersection of a side-street and a main road moderated by a roundabout. It was nasty, almost worse than the simple T-intersection beforehand. Those In Charge wouldn't believe a set of traffic lights was what was needed. The roundabout never got finished before they ripped it out and put in lights!
Oh, if you're ever driving in Melbourne, watch out for roundabouts where the tram lines go through the middle. Traffic on the roundabout has to give way to the trams, of course.
Wade.
