Comment by dwd
1 day ago
That is a very basic roundabout. I was expecting by "magic" that you would have to go round some part in reverse (clockwise for US left-hand driving). This is nothing compared to the original "magic" roundabout of Swindon, Wiltshire.
This interchange might have been better off using a diverging diamond interchange layout [1]. While not a roundabout they are "magic" and we should use them more often.
They just look confusing because at some point you are effectively driving on the wrong side of the road, but are extremely efficient. My daily commute includes one that cuts a few minutes off what it once took to negotiate the previous traditional interchange.
[1] https://en.wikipedia.org/wiki/Diverging_diamond_interchange
> This is nothing compared to the original "magic" roundabout of Swindon, Wiltshire.
There should be a law (I'd suggest Dougal's Law) describing how any discussion of road design will inevitably lead to a mention of the Magic Roundabout :D
We have one of those diverging diamond ones in the general area too (at the I90/SR18 junction). It's interesting to drive through until you get used to it.
I hit that one a few weeks ago, having apparently not been that way in quite a while. I’m down with some roundabouts, but that intersection definitely kept me in my toes.
it does note that it's satire. a lot of drivers in America have reflexive dislike of roundabouts.
this one probably is not good for a DDI because it is also supposed to be a bus interchange for a BRT project, and the buses will stop at the roundabout level.
The majority of drivers don't know the signaling rules for roundabouts so the end result is no one uses signals on them for anything and this you never know what people are going to do next when they are in one.
All in all they end up being rather unpleasant to use through no fault of their own.
Probably an instance where busses need their own level/ramps.
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