Newest System Interchange in Each State

[Buck87]

I wouldn't consider US 23/OH 823 to be a "system interchange," given that this is a freeway that connects two surface routes at either end. There are at-grades on US 23 within close proximity to the end of the Portsmouth bypass.

What about OH 823/US 52?
52 is a freeway there....though would a partial interchange be big enough to be considered a "system interchange"?

Though at the moment neither of these is open to traffic (that will hopefully change within a week)

For Ohio, I believe it is probably the two interchanges of US-23 and US-30 near Upper Sandusky, at either end of their concurrency.

What year did those get built?  the latest ones I thought of in Ohio were I-77 at the Ohio Turnpike/I-80 in the late 90s or I-80 and SR-711 in Youngstown in 2006.  Both were already opened partial intersections, but in the case of I-77/I-80 they extended the turnpike ramp from SR-21 to I-77.

The one SE of Upper Sandusky was 2004, and the one NW of Upper Sandusky was 2008.

[hbelkins]

If we're considering things like US 23 and the Portsmouth bypass, then Kentucky's entry changes from I-24/Pennyrile to US 23-119/Future US 460 south of Pikeville.

[cl94]

The only new system interchanges built in NY within the past 20 years are:

I-81/781 (newest)
I-86/99
I-84/87

That's it. As mentioned before, I-84/87 was a true Breezewood that would make Pennsylvania proud and was the only real Breezewood in NY. Traffic was required to use NY 300 (and originally, NY 17K as well). That E-ZPass-only ramp coming from the NB exit ramp was the original trumpet stem. Configuration as of 2004 was this. 86/99 was that parclo below the current elevated system interchange, which the freeway south of there tied into. This was the configuration as of the early-mid-2000s. 781 didn't exist until 6 years ago, so that movement was handled by NY 342 (which is basically unaltered).

[triplemultiplex]

If we're considering things like US 23 and the Portsmouth bypass, then Kentucky's entry changes from I-24/Pennyrile to US 23-119/Future US 460 south of Pikeville.

The OP gives his thumb's up to this junction.  Was that 2012 or 2013?
Those look like impressive rock cuts for that trumpet to boot!  Future civilizations will assume the benched hill remaining in the loop ramp is some mysterious 'pyramid'.    Thursday night on the "History" Channel.

[jon daly]

The only new system interchanges built in NY within the past 20 years are:

I-81/781 (newest)
I-86/99
I-84/87

That's it. As mentioned before, I-84/87 was a true Breezewood that would make Pennsylvania proud and was the only real Breezewood in NY. Traffic was required to use NY 300 (and originally, NY 17K as well). That E-ZPass-only ramp coming from the NB exit ramp was the original trumpet stem. Configuration as of 2004 was this. 86/99 was that parclo below the current elevated system interchange, which the freeway south of there tied into. This was the configuration as of the early-mid-2000s. 781 didn't exist until 6 years ago, so that movement was handled by NY 342 (which is basically unaltered).

This makes me wonder if the old I-84 junction with I-91 in Hartford would've been considered a Breezewood. I forget exactly how it went, but Morgan Street was involved.

[hbelkins]

If we're considering things like US 23 and the Portsmouth bypass, then Kentucky's entry changes from I-24/Pennyrile to US 23-119/Future US 460 south of Pikeville.

The OP gives his thumb's up to this junction.  Was that 2012 or 2013?
Those look like impressive rock cuts for that trumpet to boot!  Future civilizations will assume the benched hill remaining in the loop ramp is some mysterious 'pyramid'.    Thursday night on the "History" Channel.

Some of the engineers in that area call those "birthday cakes."

This was part of my 2013 Pike County, Ky. meet.

2013 Various KY pics July-Sept - 180 by H.B. Elkins, on Flickr

2013 Various KY pics July-Sept - 181 by H.B. Elkins, on Flickr

The road opened in late 2014 and I drove it a few months later.

https://www.flickr.com/photos/hbelkins/sets/72157655767545270

2015 Various KY pics Jan-June - 027 by H.B. Elkins, on Flickr

2015 Various KY pics Jan-June - 203 by H.B. Elkins, on Flickr

There are a few of these along the newer sections of US 119 between Pikeville and the state line, as well.

[cl94]

I drove through the Pikeville area (as well as all of Corridor G) after the eclipse last year. The earthwork was quite stunning.

[mrcmc888]

I believe Delaware's is DE-141 to I-95 completed somewhere in the mid-2000s or early 90s.  However, when US-301's new alignment is complete, 301 to I-95 and DE-1 will take over it

[Roadsguy]

I believe Delaware's is DE-141 to I-95 completed somewhere in the mid-2000s or early 90s.  However, when US-301's new alignment is complete, 301 to I-95 and DE-1 will take over it

This DE 141 and I-95? Historic Aerials shows it being original to I-95's construction in mostly its current form, with the Newport Freeway being built to it in the 1970s.

[Mr_Northside]

Some of the engineers in that area call those "birthday cakes."

Just my opinion, but I'd steer more toward a "wedding cake" than birthday.  It looks cool, either way.

[triplemultiplex]

^^ 3MX, did you miss my comment on the first page (regarding Vermont)?

What's the chronology of that junction between US 7 and VT 279?  I thought something was pretty new down there and that double trumpet situation meets my criteria.

[froggie]

Parts of VT 279 are new, but the double-trumpet has existed since the mid-1970s and has been in-use since that time, initially as a connector to VT 67A.

[route56]

I would not consider "KS 10/32nd St" (presumably K-10/23rd Street is meant) to be a system interchange in general, let alone to the specific criteria outlined in the OP that seem to be aimed at excluding phased construction.  It is a three-level wye and all movements are free-flowing, but it does not connect two freeways.  The SLT to the west is a simple extension of the older K-10 freeway and 23rd Street is a surface arterial.

23rd Street between K-10 and Harper is more of an "expressway" than a plain surface arterial. Aside from the relatively new stoplight at O'Connell Road, it hasn't changed much since it was first constructed (which, BTW, pre-dates the K-10 freeway between Lawrence and K-7). I would consider a freeway-to-expressway connection to be within the 'system interchange' criteria.

The interchange itself was constructed as part of the east leg of the South Lawrence Trafficway, and connects the SLT to 23rd Street and the older K-10 freeway. Even though the "through" route was re-aligned (from K-10 -> 23rd Street to K-10 -> SLT) there is a new road involved; therefore, this is a new interchange.

Incidentally, "32nd Street" was the designation of the alignment of the SLT that was chosen and built (surviving a NEPA challenge in both the Circuit and Appeals Courts)