I think the 4-level stack at Interstate 20 and US 175 in Balch Springs, TX is probably overkill.
Post Merge: July 03, 2012, 01:59:15 PM
It probably gets as many VPD as Texas Toll 49.
The US 322/522/22 interchange in Lewistown, PA, is debatably overkill. It's out in the middle of nowhere.
Then there's I-95 at PA 413 (Exit 40, the one south of the Turnpike.) However, this was meant to go somewhere, so it's understandable.
SR 23 and SR 118 in Moorpark.
It's a simple curve. Nah.
Quote from: NE2 on July 03, 2012, 03:16:58 PM
SR 23 and SR 118 in Moorpark.
High-Five interchange in Dallas. Should've been a roundabout.
Over/under how many more threads blawp starts that troll the state of Texas?
I-8/CA-163. one of the most direct paths is a u-turn from CA-163 south to CA-163 north. who uses that??
also I-5/I-8/CA-209. too many strangely located exit choices and mainline lane drops, just to accommodate an arterial.
I-83, I-283, US 322, Swatara, PA (near Harrisburg):
http://goo.gl/maps/khXT
101 at Cesar Chavez (Army)/Potrero (featuring Bayshore Boulevard) in SF
US 61/I-310 in Louisiana. A stack interchange in the middle of the damn swamp. US 61 has been bypassed by I-10, I-310 is used from US 90 to I-10. I've NEVER seen anyone using the offramps.
Quote from: Roadsguy on July 03, 2012, 03:08:25 PM
The US 322/522/22 interchange in Lewistown, PA, is debatably overkill. It's out in the middle of nowhere.
Then there's I-95 at PA 413 (Exit 40, the one south of the Turnpike.) However, this was meant to go somewhere, so it's understandable.
Actually, I learned that it wasn't meant to go anywhere, but rather I-895 would have headed due south from there. The ramps that did get built would have looked a lot saner in context.
Quote from: Steve on July 03, 2012, 07:35:54 PM
Quote from: Roadsguy on July 03, 2012, 03:08:25 PM
The US 322/522/22 interchange in Lewistown, PA, is debatably overkill. It's out in the middle of nowhere.
Then there's I-95 at PA 413 (Exit 40, the one south of the Turnpike.) However, this was meant to go somewhere, so it's understandable.
Actually, I learned that it wasn't meant to go anywhere, but rather I-895 would have headed due south from there. The ramps that did get built would have looked a lot saner in context.
The spur at one point was planned to continue east to US 13, I've seen it marked as proposed on an early-80s Gousha maps.
For several years it looked like the I-270 interchange at Easton Way was pointlessly overbuilt. It made a bit more sense over the years as OH 161 was upgraded between Columbus and Granville.
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
I
hate love hate love you .
Quote from: elsmere241 on July 03, 2012, 06:22:35 PM
I-83, I-283, US 322, Swatara, PA (near Harrisburg):
http://goo.gl/maps/khXT
For all that, the freeways through there still only have 2 mainline lanes each way.
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
No, it should have been an at-grade intersection. :-)
I-80/US 46/NJ 94, Columbia, NJ.
'nuff said!
:spin:
Mike
The Alemany Maze at the junction of US 101/I-280.
The I-710/I-10 interchange at South Pasadena
The East LA interchange.
The ramp from I-80 into the Transbay Terminal.
Quote from: mcdonaat on July 03, 2012, 06:34:02 PM
US 61/I-310 in Louisiana. A stack interchange in the middle of the damn swamp. US 61 has been bypassed by I-10, I-310 is used from US 90 to I-10. I've NEVER seen anyone using the offramps.
You haven't been around there during shift change from the Norco refinery. Also provides access to the freight portion of Armstrong Airport.
Mind you, when that interchange was built, Louisiana was still intending for I-310 to be I-410.
Quote from: vtk on July 03, 2012, 07:58:16 PM
For several years it looked like the I-270 interchange at Easton Way was pointlessly overbuilt. It made a bit more sense over the years as OH 161 was upgraded between Columbus and Granville.
Blame Les Wexner (for the overbuild).
Quote from: Hot Rod Hootenanny on July 04, 2012, 12:24:30 AM
Quote from: mcdonaat on July 03, 2012, 06:34:02 PM
US 61/I-310 in Louisiana. A stack interchange in the middle of the damn swamp. US 61 has been bypassed by I-10, I-310 is used from US 90 to I-10. I've NEVER seen anyone using the offramps.
You haven't been around there during shift change from the Norco refinery. Also provides access to the freight portion of Armstrong Airport.
Mind you, when that interchange was built, Louisiana was still intending for I-310 to be I-410.
Still seems silly to have it built the way it is. Seems very out of place in the middle of the swamp! I haven't been down Airline in forever, electing to take the River Road (LA 48) instead. However... is a stack of that size really needed in the swamp, especially when a fly ramp system could do better purpose?
Quote from: mcdonaat on July 04, 2012, 12:32:38 AM
Quote from: Hot Rod Hootenanny on July 04, 2012, 12:24:30 AM
Quote from: mcdonaat on July 03, 2012, 06:34:02 PM
US 61/I-310 in Louisiana. A stack interchange in the middle of the damn swamp. US 61 has been bypassed by I-10, I-310 is used from US 90 to I-10. I've NEVER seen anyone using the offramps.
You haven't been around there during shift change from the Norco refinery. Also provides access to the freight portion of Armstrong Airport.
Mind you, when that interchange was built, Louisiana was still intending for I-310 to be I-410.
Still seems silly to have it built the way it is. Seems very out of place in the middle of the swamp! I haven't been down Airline in forever, electing to take the River Road (LA 48) instead. However... is a stack of that size really needed in the swamp, especially when a fly ramp system could do better purpose?
Not sure what other options Huey Long had in routing Airline Highway back in the 1930s other than through the swamp.
Otherwise, I don't see what geology has to do with the interchange design, I-310 is 4 lanes, US 61 is 4 lanes. So, to keep all directions free flowing, without traffic lights, the state decided to build a stack instead of a cloverleaf.
Quote from: Hot Rod Hootenanny on July 04, 2012, 12:25:29 AM
Quote from: vtk on July 03, 2012, 07:58:16 PM
For several years it looked like the I-270 interchange at Easton Way was pointlessly overbuilt. It made a bit more sense over the years as OH 161 was upgraded between Columbus and Granville.
Blame Les Wexner (for the overbuild).
Sure he caused the problem, but he put the solution in place before the problem existed. I have no beef with that.
The I-95 and FL 528 interchange near Cocoa, FL. It has pointless ramps from EB to NB and SB to WB as FL 407 covers those movements quite well. It originally did not have them until either the mid or late 90's, but it was done to make it a complete interchange as it was missing some movements. The NB to EB and WB to SB were added to it in addition as you previously had to do a Breezewood via FL 524. This part was understandable, but the previous was always a shortcut and still to this day used as primary connection for the once missing movements.
Quote from: Beltway on July 03, 2012, 09:57:23 PM
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
No, it should have been an at-grade intersection. :-)
:spin: :spin: A roundabout
IS an at-grade intersection. :spin: :spin:
Quote from: kphoger on July 04, 2012, 10:29:45 AM
Quote from: Beltway on July 03, 2012, 09:57:23 PM
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
No, it should have been an at-grade intersection. :-)
:spin: :spin: A roundabout IS an at-grade intersection. :spin: :spin:
At-grade, 4-way, signalized intersection ... :-)
Quote from: Beltway on July 04, 2012, 01:53:08 PM
Quote from: kphoger on July 04, 2012, 10:29:45 AM
Quote from: Beltway on July 03, 2012, 09:57:23 PM
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
No, it should have been an at-grade intersection. :-)
:spin: :spin: A roundabout IS an at-grade intersection. :spin: :spin:
At-grade, 4-way, signalized intersection ... :-)
Nah a 4-way stop would be sufficient...
Quote from: on_wisconsin on July 04, 2012, 02:07:33 PM
Quote from: Beltway on July 04, 2012, 01:53:08 PM
Quote from: kphoger on July 04, 2012, 10:29:45 AM
Quote from: Beltway on July 03, 2012, 09:57:23 PM
Quote from: Chris on July 03, 2012, 03:31:23 PM
High-Five interchange in Dallas. Should've been a roundabout.
No, it should have been an at-grade intersection. :-)
:spin: :spin: A roundabout IS an at-grade intersection. :spin: :spin:
At-grade, 4-way, signalized intersection ... :-)
Nah a 4-way stop would be sufficient...
4-way.
(no stop. no yield). Have fun guys.
My only gripe with the High Five is how the flyovers taper down to one lane when they merge. It causes a huge backup at peak hours. Hopefully they can fix this problem as they rebuild LBJ.
http://goo.gl/maps/KrDf - M74 and A723 south of Glasgow, Scotland.
I'd argue there might have been some way to simplify the interchange between I-10 and I-45 on Houston. It seems to work, but for a driver from out of state there is a real "WTF?!" type response with I-45 running between the 10 EB and WB lanes with a left hand short ramp onto 45....Aggggh. A little too elaborate, especially in a city that has beautifully designed stacks at nearly every other freeway interchange. Didn't like that one, and that's coming from southern Califorina!
Quote from: ftballfan on July 05, 2012, 07:43:38 PM
http://goo.gl/maps/KrDf - M74 and A723 south of Glasgow, Scotland.
Not so much pointlessly elaborate but just a really twisted looking turbine interchange (and turning left + right is separated). Has probably something to do with having enough space to properly grade things, and remove the need to have more than two-levels of roads.
Actually that 'octopus' is due to two motorway projects not happening (one north from that interchange to Cumbernauld, one SW from that interchange round the bottom of East Kilbride and ending on the M8 at Paisley).
It might look fairly normal for your North American eyes, where these things are common, but I can assure you that this is very over-elaborate for a British Motorway interchanging with an A road (IIRC it's the only fully freeflow full-access Motorway-A road junction in the country). That would be a standard roundabout interchange anywhere else, especially given that the road just peters out very soon after in each direction as it hits Motherwell and Hamilton town centres.
Even the A282/M25 interchange with the (6-8-lanes) A2 is a 3-level roundabout with two directional ramps linking North and East. Other junctions, including interchanges between motorways, aren't even lucky enough to have directional ramps.
When I drove on US 175 in Dallas, it had quite a bit of traffic on it, and it was a Saturday afternoon. It wasn't choked but it wasn't empty either. I can imagine it gets bad around the 175/310 interchange during rush hour.
If you're unfamiliar with the Texas High Five, here's a video: http://www.youtube.com/watch?v=kN2qSe9V-1w
The I 696 Mound Road interchange in Warren is a bit Elaborate. However when it was being built, Mound Road was planed to be built as a freeway. https://maps.google.com/maps?q=warren+mi&ll=42.487669,-83.041964&spn=0.038293,0.104628&oe=utf-8&client=firefox-a&hnear=Warren,+Macomb,+Michigan&gl=us&t=m&z=14
I-476, I-81 and US 6/11 in Pennsylvania
I-65, I-90 and US 12/20 in Gary, IN
Quote from: mcdonaat on July 03, 2012, 06:34:02 PM
US 61/I-310 in Louisiana. A stack interchange in the middle of the damn swamp. US 61 has been bypassed by I-10, I-310 is used from US 90 to I-10. I've NEVER seen anyone using the offramps.
Two words: Industrial access.
I'll just say any freeway to freeway interchange in Los Angeles, California.
Quote from: NE2 on July 03, 2012, 03:16:58 PM
SR 23 and SR 118 in Moorpark.
I live in California and still had to google this. OK, it's a joke (?), but map links are always appreciated.
I-10 at I-20.
Quote from: national highway 1 on July 06, 2012, 10:10:02 PMI-476, I-81 and US 6/11 in Pennsylvania
That's not really
elaborate, but just a goofball design. If you want elaborate, go a few exits down 81, though that's all-freeway.
Quote from: Roadsguy on July 07, 2012, 09:16:29 AM
Quote from: national highway 1 on July 06, 2012, 10:10:02 PMI-476, I-81 and US 6/11 in Pennsylvania
That's not really elaborate, but just a goofball design. If you want elaborate, go a few exits down 81, though that's all-freeway.
I was never on the 81/84/380/6 interchange until it was rebuilt, but it looks like drastic steps were taken to keep I-81 as the through route. I wonder what the traffic counts are here, and if most traffic heading north on I-81 continues east on I-84?
I-70, I-76 and US 30. :-D
Quote from: Bickendan on July 07, 2012, 04:44:51 AM
I-10 at I-20.
What's wrong with that? It's just a simple Y interchange with a sharp 90
o ramp and a u-turn bay for the low traffic movements. Similar to the junction of the Hume Hwy (NH31) and the Federal Hwy (NH23) south of Goulburn (http://goo.gl/maps/YPUZ) which the traffic from Sydney to Canberra uses. Also this interchange between the Hume Hwy (NH31) and the Snowy Mountains Hwy (NR18) south of Gundagai (http://goo.gl/maps/CB3H).
I think he's arguing that traffic counts are so low that those movements aren't even needed.
I-76 Schuylkill Expy, Oregon Ave, Passyunk Ave, and 26th St. in South Philly. You know it's special when the Interstate has the fewest number of through lanes passing through the center of the interchange.
I-295/NJ42/I76/I676 in NJ, yes 676 ends outside of the main interchange, but is a contributing factor.
And the mess of I-78 and US1/NJTP at the newark NJ airport.
How about near Paxtang, PA. You have that I-83,I-283, and US 322 interchange that everyone has complained about at one time or another, but there are two southbound exits for Paxton Street on I-83. If you exit at Eisehower Boulevard exit that is signed as US 322 East in addition to Derry Street and also has Paxton Street on its sign. The thing is its not another exit for the same, but if you take the US 322 exit to Paxton Street it will lead you back on to I-83 to exit at the other ramp that is for Paxton Street proper. It has no purpose as you are getting back on the same road in what you can do if you simply stay on it in the first place Furthermore, there is no entrance ramp either from Paxton to Northbound I-83, the opposite way of this travel.
Then in Mahwah, NJ there is no Northbound Exit to NJ 17 Southbound at least directly. The NJ 17 South exit is a U Turn ramp that actually merges with the very long Northbound NJ 17 to Southbound I-287 on ramp where it later merges with its southbound counterpart. There you exit at the I-287 Southbound NJ 17 Southbound exit on the left side, where you must weave creating a safety concern as you merge from the right side of I-287 Southbound just south of the NY State Line.
Quote from: national highway 1 on July 08, 2012, 07:10:28 AM
Quote from: Bickendan on July 07, 2012, 04:44:51 AM
I-10 at I-20.
What's wrong with that? It's just a simple Y interchange with a sharp 90o ramp and a u-turn bay for the low traffic movements. Similar to the junction of the Hume Hwy (NH31) and the Federal Hwy (NH23) south of Goulburn (http://goo.gl/maps/YPUZ) which the traffic from Sydney to Canberra uses. Also this interchange between the Hume Hwy (NH31) and the Snowy Mountains Hwy (NR18) south of Gundagai (http://goo.gl/maps/CB3H).
It was a smart-ass post because I-10 and 20 is about as simple of a full directional limited-access interchange as you can get, though it's interesting to see two Australian examples brought up. I'm left wondering, though: The first interchange near Yarra is missing the EB 31 to SB 23 movement, and the second is missing the NB 18 to EB 31 movement...
Quote from: roadman65 on July 10, 2012, 10:28:57 PM
...there is no entrance ramp either from Paxton to Northbound I-83, the opposite way of this travel.
None direct, but if you go over Paxton EB to Eisenhower Blvd. and turn north (where it debatably turns into a freeway), you feed right into 83 NB.
The 'bump' between I-76 and I-80 near Youngstown, OH.
Quote from: national highway 1 on July 11, 2012, 08:30:49 PM
The 'bump' between I-76 and I-80 near Youngstown, OH.
A double trumpet interchange between a toll road and a freeway is pointlessly elaborate?
Quote from: Hot Rod Hootenanny on July 11, 2012, 10:28:20 PM
Quote from: national highway 1 on July 11, 2012, 08:30:49 PM
The 'bump' between I-76 and I-80 near Youngstown, OH.
A double trumpet interchange between a toll road and a freeway is pointlessly elaborate?
A simple roundabout would do.
Quote from: Steve on July 11, 2012, 10:45:45 PM
Quote from: Hot Rod Hootenanny on July 11, 2012, 10:28:20 PM
Quote from: national highway 1 on July 11, 2012, 08:30:49 PM
The 'bump' between I-76 and I-80 near Youngstown, OH.
A double trumpet interchange between a toll road and a freeway is pointlessly elaborate?
A simple roundabout would do.
Or a stack.
Wouldn't toll booth placement on a stack be pointlessly elaborate?
This thread is getting pointlessly elaborate :P
Quote from: Hot Rod Hootenanny on July 11, 2012, 10:28:20 PM
Quote from: national highway 1 on July 11, 2012, 08:30:49 PM
The 'bump' between I-76 and I-80 near Youngstown, OH.
A double trumpet interchange between a toll road and a freeway is pointlessly elaborate?
Actually, that interchange now has (and has had for years) a connection to a nearby county route as well (To/From the Turnpike only), which makes the interchange a good bit more elaborate. How "pointless" it is is completely up to one's opinion.
Quote from: Hot Rod Hootenanny on July 11, 2012, 10:28:20 PM
Quote from: national highway 1 on July 11, 2012, 08:30:49 PM
The 'bump' between I-76 and I-80 near Youngstown, OH.
A double trumpet interchange between a toll road and a freeway is pointlessly elaborate?
Maybe he meant my version of it in the Redesigning Interchanges thread.
Any interchange along 101 or 280 in the city of SF, with the exception of maybe the 1/280 split in Daly City.
Quote from: flowmotion on July 07, 2012, 02:58:04 AM
Quote from: NE2 on July 03, 2012, 03:16:58 PM
SR 23 and SR 118 in Moorpark.
I live in California and still had to google this. OK, it's a joke (?), but map links are always appreciated.
According to the map, each exits on/off the freeway. So if someone were not paying attention, he or she would be driving along on one SR and suddenly find himself/herself on the other. Not a problem for road geeks of course, but the average driver - who would probably only be looking for an exit if he expected to change routes - must have fits...
Quote from: US81 on July 13, 2012, 03:37:47 PM
Quote from: flowmotion on July 07, 2012, 02:58:04 AM
Quote from: NE2 on July 03, 2012, 03:16:58 PM
SR 23 and SR 118 in Moorpark.
I live in California and still had to google this. OK, it's a joke (?), but map links are always appreciated.
According to the map, each exits on/off the freeway. So if someone were not paying attention, he or she would be driving along on one SR and suddenly find himself/herself on the other. Not a problem for road geeks of course, but the average driver - who would probably only be looking for an exit if he expected to change routes - must have fits...
But you can't get lost if you follow the signs (http://www.flickr.com/photos/therealkurumi/3154326855/in/set-72157623657705448) :)
Quote from: hbelkins on July 07, 2012, 01:16:32 PM
Quote from: Roadsguy on July 07, 2012, 09:16:29 AM
Quote from: national highway 1 on July 06, 2012, 10:10:02 PMI-476, I-81 and US 6/11 in Pennsylvania
That's not really elaborate, but just a goofball design. If you want elaborate, go a few exits down 81, though that's all-freeway.
I was never on the 81/84/380/6 interchange until it was rebuilt, but it looks like drastic steps were taken to keep I-81 as the through route. I wonder what the traffic counts are here, and if most traffic heading north on I-81 continues east on I-84?
It would be hard to say without traffic counts what the overall numbers are. All I can say is personally, I've only done I-81 North to I-84 east once in my life and the same for I-81 north to US 6 east once, the other umpteen-hundred times I've been through on 81 north, I've been staying on 81 north.
To be fair, even when living in PA, I never traveled much to the north or east through Scranton, it was always a destination city.
As for I-476, I-81 and US 6/11, most of us know that's an artifact of 81 going to New York state instead of the Turnpike as originally planned.
Quote from: ibagli on July 12, 2012, 02:26:31 AM
Wouldn't toll booth placement on a stack be pointlessly elaborate?
Or do what they're doing at 95 in (the other side of) PA, as well as to give a connection to 79: put a high-speed toll booth west of the interchange, and make the bump a stack.
^^^
Of course, that would involve taking the Ohio Turnpike east of the interchange off the ticket system and either free or barrier tolls.
The one upside to all electronic tolling is that you can place the gantries almost anywhere and use more conventional interchanges places like here or in Burns Harbor, IN when I-80 leaves the Indiana toll road and joins I-94.
Quote from: kurumi on July 13, 2012, 09:23:04 PM
Quote from: US81 on July 13, 2012, 03:37:47 PM
Quote from: flowmotion on July 07, 2012, 02:58:04 AM
Quote from: NE2 on July 03, 2012, 03:16:58 PM
SR 23 and SR 118 in Moorpark.
I live in California and still had to google this. OK, it's a joke (?), but map links are always appreciated.
According to the map, each exits on/off the freeway. So if someone were not paying attention, he or she would be driving along on one SR and suddenly find himself/herself on the other. Not a problem for road geeks of course, but the average driver - who would probably only be looking for an exit if he expected to change routes - must have fits...
But you can't get lost if you follow the signs (http://www.flickr.com/photos/therealkurumi/3154326855/in/set-72157623657705448) :)
Now why would I do that? My GPS is never wrong!
I-55/MS 463 at Madison, because it has bricks in the design. The mayor there insists on everything in Madison be built in brick.
MD 32 at Denington Lane. (http://goo.gl/maps/4xCq1) Not so much pointlessly elaborate as just pointless.
Quote from: kj3400 on November 13, 2012, 04:50:05 PM
MD 32 at Denington Lane. (http://goo.gl/maps/4xCq1) Not so much pointlessly elaborate as just pointless.
That's a bizarre one --- never seen anything like that before.
It's an exit for NSA employees only, so maybe they want to give accidental exiters a second chance. Of course the roundabout also prevents an at-grade crossing of the two ramps. And the median was already wide: http://mapper.acme.com/?ll=39.10083,-76.76929&z=17&t=O
(https://www.aaroads.com/mid-atlantic/maryland030/md-032_eb_exit_009_02.jpg)
Quote from: NE2 on November 13, 2012, 08:09:32 PM
Of course the roundabout also prevents an at-grade crossing of the two ramps. And the median was already wide
That's the main thing, IMO. No need to acquire land for a trumpet interchange when that little nugget would suffice.
Quote from: NE2 on November 13, 2012, 08:09:32 PM
It's an exit for NSA employees only, so maybe they want to give accidental exiters a second chance.
I once got off at the exit to Camp Pendleton on I-5. the guard just told me how to turn around most effectively. I would imagine the NSA would be able to hide the Sooper Sekrit stuff well away from the guard shack.
That is an odd-looking sign symbol on the left.
:spin:
Also, from what I could gather from the aerial images of the area, the really juicy parts of the NSA grounds have two more checkpoints to pass after the main guard shack.
:-o
Mike
The College Park Interchange, where I-95 and I-495 meet. It would've made sense had the southward extension of I-95 into Washington been built, but we'll never know now.
Quote from: NE2 on November 13, 2012, 08:09:32 PM
It's an exit for NSA employees only, so maybe they want to give accidental exiters a second chance. Of course the roundabout also prevents an at-grade crossing of the two ramps. And the median was already wide: http://mapper.acme.com/?ll=39.10083,-76.76929&z=17&t=O
-image-
I just think it would be less pointless if there were more than one road or one pair of slips connected to the roundabout.
What the Emporia (KS) interchange used to look like.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fi1092.photobucket.com%2Falbums%2Fi410%2Fkphoger%2Femporia.png&hash=f4985792cc50be1e59e05ab1682ee41fc408b641)
Quote from: kphoger on November 15, 2012, 05:24:44 PM
What the Emporia (KS) interchange used to look like.
Interestingly, from Google Maps, you can still see vestiges of the original configuration today:
https://maps.google.com/maps?q=emporia,+ks&hl=en&ll=38.413332,-96.232445&spn=0.012997,0.019011&sll=37.269174,-119.306607&sspn=13.502373,19.467773&t=h&hnear=Emporia,+Lyon,+Kansas&z=16
The now-removed original trumpet dates back to the 1950s construction of the Kansas Turnpike, with the cul-de-sac to US 50 being part of the old junction:
http://www.historicaerials.com/aerials.php?scale=2.02258649687544E-05&lat=38.4138687491774&lon=-96.2347961128282&year=1959
The configuration from that topographic map above was in place as late as 2006 according to Historic Aerials.
Yeah, it was only a few years ago that they reconfigured it.
Also, either I misunderstand what road feature you're referring to, or you misunderstand what a cul-de-sac is.
Quote from: kphoger on November 15, 2012, 06:41:40 PM
Also, either I misunderstand what road feature you're referring to, or you misunderstand what a cul-de-sac is.
The road marked in the topographic map heading north from US 50 that has a dead-end. I guess that's a better way of phrasing it
OK, now it all makes sense to me. Thanks!
Looks like it's now a KTA service drive.
On the Emporia example...I wonder why that wasn't originally built as a diamond. Surely they wouldn't make an extra bridge just for the fun of it.
The NSA example is interesting. On the one hand, they reduce bridge width by not allowing the direct south to south on movement (see the interchange to the north for a bigger bridge). But they could have reduced bridge area more by tightening the radius in the median and squaring up the bridge. Obviously the traffic going into a roundabout doesn't need to be moving fast, why keep a bigger radius? And the left exit and entrance probably make it worse than anything else. Assuming there was no space to the west, wonder why they didn't shift the whole SB alignment to the east and put in a tight diamond.
Quote from: johndoe on November 15, 2012, 08:49:28 PM
On the Emporia example...I wonder why that wasn't originally built as a diamond. Surely they wouldn't make an extra bridge just for the fun of it.
Probably to route all the traffic through one toll plaza.
Quote from: Scott5114 on November 15, 2012, 10:30:51 PMQuote from: johndoe on November 15, 2012, 08:49:28 PMOn the Emporia example...I wonder why that wasn't originally built as a diamond. Surely they wouldn't make an extra bridge just for the fun of it.
Probably to route all the traffic through one toll plaza.
I don't think that can have been the reason. Under both the original and current configurations, all traffic interfaces with the Turnpike through a single toll plaza. That is also true of the diamond configurations that have been used elsewhere on the Turnpike, notably at Cassoday and the new Lawrence interchanges.
What I think happened is that the original designers of the Turnpike attached excessive importance to free-flow movement between the Turnpike mainline and the toll plazas, and at Emporia between the toll plaza and the various US 50 links. This is of little benefit to traffic entering or leaving the Turnpike since the toll plaza is in all cases either an obligatory stop or a transit down a K-Tag chute which is speed-limited to 20 MPH. In the particular case of the Emporia interchange, it sterilized a lot of ground (which is now used for KTA maintenance functions) and resulted in the necessity to maintain three superfluous grade separation structures (five were demolished when the interchange was reconfigured and only two were reinstated, both in different locations). Also, perversely, it assigned direct routings to the low-volume movements (such as Emporia city street to Turnpike in either direction) and twisty and convoluted ones to the high-volume or long-distance movements (such as Turnpike NB to free I-35 NB or US 50 EB to Turnpike).
In short, the original design fetishized free flow at the expense of land usage, simplicity in layout, and driver expectancy. In 1956 it would have been justified partly by the expectation that the Turnpike would be made toll-free when the bonds were paid off, since this would have removed obligatory stops at the tollbooths. Now, almost sixty years later, it has become clear that bond renewals will prolong Turnpike tolls and with them live tollbooths for the foreseeable future. When traffic has to stop at a toll plaza anyway, it makes little sense to shave a few seconds of time by substituting trumpet ramps (which can and do cause truck rollovers) for roundabouts or stop control at the ramp terminals.
I don't particularly welcome such a development but I can easily see the Turnpike's existing trumpet interchanges being reconstructed out of existence over the next twenty or thirty years.
Quote from: drummer_evans_aki on July 07, 2012, 12:39:22 AM
I'll just say any freeway to freeway interchange in Los Angeles, California.
Hey, Los Angeles has great interchanges, you can fly over them at up to 60 MPH only to reach the end and do 15 MPH on the freeway.