
Diverging Diamond Interchange - mojoe
https://en.wikipedia.org/wiki/Diverging_diamond_interchange
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tdupree
We are getting one here in Naperville, IL. They put out a pretty decent video
showing how it will work and what it will look like when they are all done.

[https://www.youtube.com/watch?v=oSWjDbWnRzQ](https://www.youtube.com/watch?v=oSWjDbWnRzQ)

[http://www.naperville.il.us/route59expansion.aspx](http://www.naperville.il.us/route59expansion.aspx)

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nsnick
Utah has one. I think they are more common when the non freeway road has very
high levels of traffic.

An even more efficient interchange is the roundabout interchange
[https://en.wikipedia.org/wiki/Roundabout_interchange](https://en.wikipedia.org/wiki/Roundabout_interchange)

The only problems with the roundabout interchange are that you need two
different bridges spaced a distance apart which can add construction costs and
they require more area than a standard interchange, although about the same as
a clover leaf.

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knz
Minnesota has one near the airport
([http://www.dot.state.mn.us/funding/projects/bloomington.html](http://www.dot.state.mn.us/funding/projects/bloomington.html))
that also has a light rail line running through it. It seems to work well but
is definitely a little alarming the first time you drive through it.

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mojoe
Colorado is putting a diverging diamond interchange in near where I live in
Boulder county. Work will be finishing soon and I was wondering if any HNers
have had experience with these types of interchanges. It looks very promising,
and hopefully drivers will get used to it quickly!

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jpmc
Where I live we have 5-6 and they have worked great. The first time through
can be interesting. Years later they are just a normal part of the the road.
Everything is clearly marked and lanes are painted brightly. The upgraded
intersections are very quick to get through now. In the past you could wait
six or seven light cycles before getting through. Now you might have one short
stop.

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bobm_kite9
In the UK, we have something similar to this for most of our motorway
junctions, except that the traffic lights are replaced by roundabouts and
there's no need for changing sides of the road.

I take it all this extra complexity is just to avoid roundabouts?

