Strange Interchanges

[1995hoo]

I don't know if it necessarily qualifies as "strange" so much as "unusual" in that it's unusual in a good way: I-395 and VA-7 (King Street) in Arlington, Virginia, is a modified cloverleaf design where traffic leaving either road in either direction takes a single ramp that then splits–the usual weave area on a cloverleaf with the merge lane connecting the loop-around ramps is eliminated because there are only two loop-around ramps.

http://maps.google.com/?ie=UTF8&ll=38.835111,-77.097577&spn=0.006193,0.016512&t=k&z=17


But of the truly strange ones, I'd put the one outside Short Hills Mall in New Jersey either at or near the top of the list simply because of its stupid design. I've long that New Jersey's basic theory for interchange design is to sketch out the essential part, then just throw in as many random ramps as are needed to complete the full set of movements. Problem at Short Hills is that they didn't do that. If you look at the linked map below, NJ-24 enters from the top center. Route 124 leaves to the left center. Try coming down from the top of the map on NJ-24 and then using the interchange to go west on 124. This is what you have to do: (1) Take the exit on the right. (2) Pass under the overpass and immediately take the loop-around ramp on the right. (3) Cross over the overpass you just went under and then take the next exit on the right for the loop-around ramp that runs between the golf course and that building. (4) Make a right at the bottom of the ramp onto JFK Parkway heading back towards the mall. (5) Pass under the two overpasses (the first of which you've already passed under once and crossed once) and then take the loop-around ramp on the right just to the north of NJ-24; this ramp carries you back towards NJ-24 going back in the direction you started from. (6) Then take the second loop-around ramp on the right to access the ramp to westbound Route 124.

It seems like it would have been very easy for them simply to have stuck in a small ramp at the western corner of this interchange to allow for this maneuver, but they didn't (I do not know whether the presence of that water nearby might have been an issue).

http://maps.google.com/?ie=UTF8&ll=40.739258,-74.368579&spn=0.006024,0.016512&t=k&z=17

[ftballfan]

I-76/I-376 (east)/US-22 in Monroeville, PA

http://maps.google.com/?ie=UTF8&t=k&ll=40.438259,-79.756215&spn=0.006647,0.028067&z=16

[Alps]

But of the truly strange ones, I'd put the one outside Short Hills Mall in New Jersey either at or near the top of the list simply because of its stupid design. I've long that New Jersey's basic theory for interchange design is to sketch out the essential part, then just throw in as many random ramps as are needed to complete the full set of movements. Problem at Short Hills is that they didn't do that. If you look at the linked map below, NJ-24 enters from the top center. Route 124 leaves to the left center. Try coming down from the top of the map on NJ-24 and then using the interchange to go west on 124. This is what you have to do: (1) Take the exit on the right. (2) Pass under the overpass and immediately take the loop-around ramp on the right. (3) Cross over the overpass you just went under and then take the next exit on the right for the loop-around ramp that runs between the golf course and that building. (4) Make a right at the bottom of the ramp onto JFK Parkway heading back towards the mall. (5) Pass under the two overpasses (the first of which you've already passed under once and crossed once) and then take the loop-around ramp on the right just to the north of NJ-24; this ramp carries you back towards NJ-24 going back in the direction you started from. (6) Then take the second loop-around ramp on the right to access the ramp to westbound Route 124.

It seems like it would have been very easy for them simply to have stuck in a small ramp at the western corner of this interchange to allow for this maneuver, but they didn't (I do not know whether the presence of that water nearby might have been an issue).

http://maps.google.com/?ie=UTF8&ll=40.739258,-74.368579&spn=0.006024,0.016512&t=k&z=17

This was omission by design. Interchange 5, with the ghost ramps to the west, was intended to serve the missing movement you speak of by having traffic use 5A and head south to NJ 124 in Chatham. But now with 5 miles between exits, it could make more sense (given enough movements) to go to Chatham via 24 E-124W than to use the 510W exit and take Park Ave. to 124 E. (Though Park has been fairly well upgraded to try to help, you get stuck in Madison.)

[mightyace]

I-76/I-376 (east)/US-22 in Monroeville, PA

http://maps.google.com/?ie=UTF8&t=k&ll=40.438259,-79.756215&spn=0.006647,0.028067&z=16

The main reason for this design was to reuse most of the existing Turnpike interchange as possible.  It looks like only the ramp from Bus US 22 East to the Turnpike was altered from the original design.  (Of course, you Pittsburgh resident feel free to correct me if I'm wrong.)

[Mr_Northside]

I-76/I-376 (east)/US-22 in Monroeville, PA

I-76/I-376 (east)/US-22 in Monroeville, PA

http://maps.google.com/?ie=UTF8&t=k&ll=40.438259,-79.756215&spn=0.006647,0.028067&z=16

The main reason for this design was to reuse most of the existing Turnpike interchange as possible.  It looks like only the ramp from Bus US 22 East to the Turnpike was altered from the original design.  (Of course, you Pittsburgh resident feel free to correct me if I'm wrong.)

Sounds about right.
As I said in this tread, or a similar one, most all of the interchanges on the original I-376 Parkway East segment (and, hell, even out the Parkway West to I-79) are pretty strange when you look at them.

[ftballfan]

Sounds about right.
As I said in this tread, or a similar one, most all of the interchanges on the original I-376 Parkway East segment (and, hell, even out the Parkway West to I-79) are pretty strange when you look at them.

From looking at Google Maps, most of the interchanges along all of I-376 (even all the way to I-80) are strange. There are a few normal diamonds thrown in northwest of the airport and a cloverleaf at I-80. The western I-76/I-376 junction is also strange. It's a modified double trumpet to allow for access to PA-351. It also exits off itself heading SB near New Castle.

[PAHighways]

I-76/I-376 (east)/US-22 in Monroeville, PA

http://maps.google.com/?ie=UTF8&t=k&ll=40.438259,-79.756215&spn=0.006647,0.028067&z=16

The main reason for this design was to reuse most of the existing Turnpike interchange as possible.  It looks like only the ramp from Bus US 22 East to the Turnpike was altered from the original design.  (Of course, you Pittsburgh resident feel free to correct me if I'm wrong.)

That is the exact reason.  The original trumpet with William Penn Highway before the Monroeville bypass was built can be seen, and yes, the original ramp from then eastbound US 22 was reconfigured to allow space for the connection of then I-70.

[PAHighways]

From looking at Google Maps, most of the interchanges along all of I-376 (even all the way to I-80) are strange. There are a few normal diamonds thrown in northwest of the airport and a cloverleaf at I-80. The western I-76/I-376 junction is also strange. It's a modified double trumpet to allow for access to PA-351. It also exits off itself heading SB near New Castle.

The interchange at US 224 was recently reconfigured and eastbound I-376 was widened to two lanes at the southern US 422 interchange.  Diamonds are the standard interchanges for PTC extensions:  one half is off/on for free and the other half you pay tolls, which explains the numerous ones through Beaver and Lawrence Counties.

The 76/376 (New Castle Interchange) also had a toll plaza until 2003, whose building can still be seen, between 76 and then Turnpike 60.

[mightyace]

^^^

Having a toll plaza between two toll roads seems funny in one way.  But, back then, that part of the mainline was still ticket system and PA 60 (now I-376) was and is a barrier system.

[NE2]

There's also local access at the I-376 end of the interchange.

[PAHighways]

It may seem strange on paper, but considering it was a connection between a barrier system toll road and a ticket system toll road, it isn't that strange.  For those leaving 76, they had to surrender their ticket and those coming from 60 had to pick one up.

[roadman65]

How about the Woodbridge Tangle in New Jersey?  It was once simple, but adding the NJ 440 Freeway changed it to being most complicated.  If you look at old arieal photographs you will see that US 9 was originally in the median of the GSP.  Now its reveresed!  US 9 is the service road for the Parkway.  Only the New Brunswick Avenue ramps to and from US 9 are the same except pre-tangle days they were Exit 127 of the Parkway.  Back then you could go directly between those two roads and now from New Brunswick Avenue to the GSP you have to travel a distance on US 9 either way to get on the roadway you once had direct on ramps to.

[roadman65]

There is another in Bridgewater, NJ between US 22 and US 202 & 206.  There is no EB to SB movement anymore.  Originally there was  an exit from US 22 EB to US 202-206 SB ONLY!  When the interchange was re-configured back in 87, the project manager eliminated that ramp for a cloverleaf so that SB to EB can move due to the re-alignment of the NB US 202-206 carrigeway.  Originally there was a u-turn ramp so that EB could go NB and SB could go EB.  Also, a EB to NB ramp as well as connection to Mountain Avenue from US 22 EB was added.

Bottom line is one movement that once was is now no longer.

[SteveG1988]

http://maps.google.com/maps?q=08060&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Mt+Holly,+New+Jersey+08060&gl=us&ll=40.260534,-74.844167&spn=0.004077,0.010504&t=h&z=17

I think this interchange is strange, and the new design with roundabouts will keep it that way. I-95 north of trenton with NJ 29

[kurumi]

http://maps.google.com/maps?q=08060&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Mt+Holly,+New+Jersey+08060&gl=us&ll=40.260534,-74.844167&spn=0.004077,0.010504&t=h&z=17

I think this interchange is strange, and the new design with roundabouts will keep it that way. I-95 north of trenton with NJ 29

I pronounced that one the "thread winner" in a channelization thread in MTR back in the day

[SteveG1988]

http://maps.google.com/maps?q=08060&oe=utf-8&client=firefox-a&ie=UTF8&hq=&hnear=Mt+Holly,+New+Jersey+08060&gl=us&t=h&ll=39.872331,-75.099578&spn=0.016402,0.042014&z=15

Runner up. 35mph interstate where you have to practicaly exit the mainline to stay on it

[Stephane Dumas]

The current Decarie interchange in Montreal is a real pain for some users, left exits for A-40 west to A-15 south and A-15 north to A-40 west as well as commuters from the north service road had to take a detour to continue their route
http://www.mtq.gouv.qc.ca/portal/page/portal/Librairie/Publications/fr/regions/montreal/DIM_Decarie_exist.pdf

The MTQ will reconfigure the northern part of this interchange as phase 1 of a bigger plan for the reconfiguration of the interchange http://www.mtq.gouv.qc.ca/portal/page/portal/Librairie/Publications/fr/regions/montreal/DIM_Decarie_projet%20.pdf

[roadman65]

I have seen one recently in Metarie, LA where there is now a flyover from NB Causeway Blvd to I-10 WB that becomes the original cloverleaf ramp that was there making you do a complete figure 8 to make that movement.  I have never seen anything like it, but I must admit it is original.  Most of all it does what it is supposed to do and prevent weaving between I-10 EB to NB Causeway and NB Causeway to I-10 WB.

[brownpelican]

From Georgia: I-75/I-85/I-20 in downtown Atlanta: http://maps.google.com/maps?hl=en&ie=UTF8&ll=33.744468,-84.389999&spn=0.007262,0.028067&t=k&z=16

What's so strange about it? Looks like a decent (although very congested) urban interchange...considering it's in downtown Atlanta.

[agentsteel53]

What's so strange about it? Looks like a decent (although very congested) urban interchange...considering it's in downtown Atlanta.

not all that strange, but there is a lot of complexity with the extra ramps to and from the surface.  Hopefully it is signed well, as it could be confusing.  I have driven it several times before, but just stayed on the freeway (20 EB once, 75 SB once) and from that perspective it wasn't bad.

[brownpelican]

I have seen one recently in Metarie, LA where there is now a flyover from NB Causeway Blvd to I-10 WB that becomes the original cloverleaf ramp that was there making you do a complete figure 8 to make that movement.  I have never seen anything like it, but I must admit it is original.  Most of all it does what it is supposed to do and prevent weaving between I-10 EB to NB Causeway and NB Causeway to I-10 WB.

Before the project began, those going from I-10 West to North Causeway had to share an auxillary lane with those going from North Causeway to Veterans Blvd. The auxillary lane was very short and cause HUGE backups on I-10 West and North Causeway...directly affecting those going from North Causeway to I-10 West. They chose the design because of the limited right of way available. Here's how the finished product is supposed to work (you may have to reload a few times):



http://blog.nola.com/news_impact/2009/04/CAUSEWAY040509.swf

[WolfGuy100]

I have seen one recently in Metarie, LA where there is now a flyover from NB Causeway Blvd to I-10 WB that becomes the original cloverleaf ramp that was there making you do a complete figure 8 to make that movement.  I have never seen anything like it, but I must admit it is original.  Most of all it does what it is supposed to do and prevent weaving between I-10 EB to NB Causeway and NB Causeway to I-10 WB.

Before the project began, those going from I-10 West to North Causeway had to share an auxillary lane with those going from North Causeway to Veterans Blvd. The auxillary lane was very short and cause HUGE backups on I-10 West and North Causeway...directly affecting those going from North Causeway to I-10 West. They chose the design because of the limited right of way available. Here's how the finished product is supposed to work (you may have to reload a few times):



http://blog.nola.com/news_impact/2009/04/CAUSEWAY040509.swf

That look very...confusing.

[1995hoo]

I have seen one recently in Metarie, LA where there is now a flyover from NB Causeway Blvd to I-10 WB that becomes the original cloverleaf ramp that was there making you do a complete figure 8 to make that movement.  I have never seen anything like it, but I must admit it is original.  Most of all it does what it is supposed to do and prevent weaving between I-10 EB to NB Causeway and NB Causeway to I-10 WB.

Before the project began, those going from I-10 West to North Causeway had to share an auxillary lane with those going from North Causeway to Veterans Blvd. The auxillary lane was very short and cause HUGE backups on I-10 West and North Causeway...directly affecting those going from North Causeway to I-10 West. They chose the design because of the limited right of way available. Here's how the finished product is supposed to work (you may have to reload a few times):



http://blog.nola.com/news_impact/2009/04/CAUSEWAY040509.swf

That look very...confusing.

I think the reason it looks confusing is that it's not a three-dimensional graphic. I looked at Google Maps' satellite view to confirm what I thought I was seeing and it verified that it's a situation where you have two mainlines (I-10 and Causeway Boulevard) that each have service roads (or frontage roads) as well. What brownpelican is saying is that under the original design, traffic exiting westbound I-10 onto the northbound mainline of Causeway had to cross over with the traffic going from northbound Causeway to Veterans Boulevard, which is accessed only from the service road since Causeway passes over Veterans via an overpass.

The new design will eliminate the crossing over by putting the mainline/service road split on Causeway south of where it was and by providing a flyover ramp so that traffic from westbound I-10 will merge into the Causeway mainline after Veterans-bound traffic has already exited.

The cloverleaf part of it looks similar to. though not quite the same as, the I-395/King Street interchange in Virginia that I linked at the top of Page 3 of this thread. You exit, then you pick which way you want to go. It reduces some of the weaving and merging.

On the whole it looks like a fairly sensible idea. Here in Northern Virginia we had a similar merging problem on I-95 in Springfield just south of the Beltway (the heart of the notorious Springfield Interchange), where prior to the reconstruction all the thru traffic on I-95 (and from the western part of the Beltway bound for I-95) had to choke down to two lanes and shove left just as traffic coming from DC on I-395 bound for Springfield had to shove right. They rebuilt the interchange to separate all the movements and it's worked wonders compared to how it used to be. The one in Metairie seems like one with a similar intent on a much smaller scale. I hope it works as well as ours did and costs them less!


Edited to add: If you look at the satellite view at the following zoom level you can see it how it was. Note the area just to the right of the placemarker. That's the problematic merge area brownpelican mentions.

http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=I-10+and+Causeway+Blvd,+Metairie,+LA&aq=&sll=37.0625,-95.677068&sspn=51.089971,135.263672&ie=UTF8&hq=&hnear=N+Causeway+Blvd+%26+North+Interstate+10+Service+Rd+W,+Metairie,+Jefferson,+Louisiana+70002&ll=30.001005,-90.154109&spn=0.004868,0.008256&t=k&z=18


After you look at that, if you zoom the image out one click, or one turn of your mouse's scrolly ball, you'll see the reconstruction in progress. Looks like a pretty good job of doing it within the existing footprint.

[sandwalk]

Whitman Street Interchange in Rockford, Illinois
....it's a strange configuration of state highways and city streets in the heart of the city, without a freeway or expressway  

http://maps.google.com/maps?q=Longwood+%26+Rural&ie=UTF8&hl=en&hq=&hnear=Rural+St+%26+N+Longwood+St,+Rockford,+Winnebago,+Illinois+61107&ll=42.274165,-89.080861&spn=0.008748,0.021973&z=16

There has been talk of revamping this entire interchange and reconnecting the neighborhoods it split apart; the pavement is literally crumbling and I would not recommend driving in this area, you are 99% guaranteed to hit couple of potholes....

[mightyace]

^^^

The eastern side of the PA 61 bridge in Sunbury, PA has something similar going on.  Though, this one seems more compact and less disrupting of the local neighborhood.

http://maps.google.com/maps?f=q&source=s_q&hl=en&geocode=&q=Sunbury,+pa&aq=&sll=42.275245,-89.081161&sspn=0.007129,0.019076&ie=UTF8&hq=&hnear=Sunbury,+Northumberland,+Pennsylvania&ll=40.851865,-76.801826&spn=0.005421,0.009645&t=h&z=17

Back to yours, it looks like 251 from there north is a semi-freeway from there north with a few exits.  Was this built as a compromise to a proposed expressway that got killed?

Though, I would agree that the exit for the eastern approach to this bridge is a bit overdone.