Why are most turnpike interchanges are trumpets?

[Strider]

I don't know if there is a thread about this in the forum (if there is, I need to know).

I watched a video on YouTube about a streamer driving down Florida's Turnpike, but I can't help but wondering about one specific thing:

Almost all Turnpikes' interchanges are trumpet (I am aware of a few exceptions, but that isn't the point of my question). But my question is: Why is trumpet interchange chosen for most of the roads' interchange with the turnpikes? I don't know the history so maybe some of you who is older than me knows?

[JoePCool14]

If you're referring to interchanges like this one on the Indiana Toll Road, I always assumed it was to make building and running the tolling infrastructure easier. You only have one plaza for two directions to worry about instead of potentially 4 separate plazas, one for each ramp.

It does add costs usually in the short term to build like this, needing to build an additional bridge or two, but likely it was the better choice in the long run. They can also get more complicated, like the ITR interchange with US-31.

[I-55]

Allows toll roads using the ticket system to have a single toll barrier at an interchange rather than 4 on a diamond. Most turnpikes you get a ticket when you enter and pay a fare for your distance traveled when you get off. Trumpets put all traffic through one barrier. Trumpets also don't take up as much space and some turnpikes predate interstate standards and have less ROW acquired.

[SkyPesos]

toll booths

[hbelkins]

It allows for a closed system, where you pay to enter and exit at every interchange. This is opposed to Kentucky's system, where not every exit was tolled and it was possible for some traffic to use sections of the toll road without paying a toll.

[Ned Weasel]

An interesting thing about double trumpets (trumpet on both the turnpike and the connecting road, with a toll booth in the middle) is, if you design them right, you can keep most of the traffic to the same side going through the trumpet, rather than requiring most traffic to cross to the other side before or after the toll plaza.  That's why I actually like the New Stanton interchange on the Pennsylvania Turnpike (https://goo.gl/maps/B7c3YcpBtYbKQSKA9).  Eastbound-to-eastbound Interstate traffic stays to the left through the interchange, and westbound-to-westbound Interstate traffic stays to the right through the interchange.

[Strider]

If you're referring to interchanges like this one on the Indiana Toll Road, I always assumed it was to make building and running the tolling infrastructure easier. You only have one plaza for two directions to worry about instead of potentially 4 separate plazas, one for each ramp.

It does add costs usually in the short term to build like this, needing to build an additional bridge or two, but likely it was the better choice in the long run. They can also get more complicated, like the ITR interchange with US-31.

Yeah, my question is referring to interchange links you posted. It includes single and double trumpet interchanges 

[SkyPesos]

An interesting thing about double trumpets (trumpet on both the turnpike and the connecting road, with a toll booth in the middle) is, if you design them right, you can keep most of the traffic to the same side going through the trumpet, rather than requiring most traffic to cross to the other side before or after the toll plaza.  That's why I actually like the New Stanton interchange on the Pennsylvania Turnpike (https://goo.gl/maps/B7c3YcpBtYbKQSKA9).  Eastbound-to-eastbound Interstate traffic stays to the left through the interchange, and westbound-to-westbound Interstate traffic stays to the right through the interchange.

As long as there's E-ZPass lanes on both sides. I've seen toll booths where you could stay on one side, but that would require waiting in a cash line, or you can switch to the opposite side in the E-ZPass lane, then switch back to your side.
The New Stanton exit out of the turnpike have two E-ZPass lanes on the far left, which are best for I-76 EB to PA 66/US 119 NB, but only one for the I-70 WB traffic on the right. Though this isn't an issue anymore as the PA turnpike using open road tolling now.

[roadman65]

This thread reminds me of a former user on here named agentsteel.  If he was the first to respond, he would have responded with a sarcastic and snarky answer.

[SkyPesos]

This thread reminds me of a former user on here named agentsteel.  If he was the first to respond, he would have responded with a sarcastic and snarky answer.

NE2 would respond with a Google redirect link if he was the first.

[JoePCool14]

This thread reminds me of a former user on here named agentsteel.  If he was the first to respond, he would have responded with a sarcastic and snarky answer.

NE2 would respond with a Google redirect link if he was the first.

I should edit my first post with a Let Me Google That For You link just to really get that authentic snark.

[1995hoo]

An interesting thing about double trumpets (trumpet on both the turnpike and the connecting road, with a toll booth in the middle) is, if you design them right, you can keep most of the traffic to the same side going through the trumpet, rather than requiring most traffic to cross to the other side before or after the toll plaza.  That's why I actually like the New Stanton interchange on the Pennsylvania Turnpike (https://goo.gl/maps/B7c3YcpBtYbKQSKA9).  Eastbound-to-eastbound Interstate traffic stays to the left through the interchange, and westbound-to-westbound Interstate traffic stays to the right through the interchange.

As long as there's E-ZPass lanes on both sides. I've seen toll booths where you could stay on one side, but that would require waiting in a cash line, or you can switch to the opposite side in the E-ZPass lane, then switch back to your side.
The New Stanton exit out of the turnpike have two E-ZPass lanes on the far left, which are best for I-76 EB to PA 66/US 119 NB, but only one for the I-70 WB traffic on the right. Though this isn't an issue anymore as the PA turnpike using open road tolling now.

I recall a trip home from Pittsburgh where the overwhelming majority of traffic exiting at Breezewood was coming from Pittsburgh, thus entering the toll plaza from the left, but the only two E-ZPass Only lanes were set up on the far right. I think they did that on purpose just to annoy the majority of drivers: The date was January 2, 2011, and the overwhelming majority of the traffic consisted of Washington Capitals fans heading home from the Winter Classic in Pittsburgh the night before, in which the Caps beat Pittsburgh 3—1. I've always suspected the toll plaza personnel were disgruntled Pittsburgh fans who wanted to stick it to the victors. Most of us wound up having fun with the backup, though; the symphony of horns honking out "Let's Go Caps" and the like probably annoyed the toll plaza personnel quite a bit more than the backup annoyed us. (I normally avoid Breezewood but went that way that day solely because joining the Caps fan traffic seemed more fun. I did feel mildly sorry for the Pittsburgh fan who got a flat tire in the middle of the Allegheny Mountain Tunnel, though.)

One thing about trumpets: In theory, even with all-electronic tolling a trumpet has a mild advantage in reducing the amount of ETC equipment the agency has to install, though whether that would outweigh the added cost of an overpass in a new interchange is a separate question. I suspect it would not.

[roadman65]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

[kphoger]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

Yep.  I use the one at Haysville with some frequency.

[Avalanchez71]

Florida's Turnpike was built with trumpet interchanges to control the ticketing.  Back in the day you would get a paper ticket.  You would then present said ticket at a booth and pay the toll.

[DandyDan]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

It should be noted, though, that the exit for Tonganoxie and Eudora was a recent addition to the system, so maybe they had no good options otherwise.

[kphoger]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

It should be noted, though, that the exit for Tonganoxie and Eudora was a recent addition to the system, so maybe they had no good options otherwise.

That exit doesn't have "one toll booth still positioned to collect in all directions", though, does it?  It has four.

|roadman65| was referring to interchanges like this.

[roadman65]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

It should be noted, though, that the exit for Tonganoxie and Eudora was a recent addition to the system, so maybe they had no good options otherwise.

That exit doesn't have "one toll booth still positioned to collect in all directions", though, does it?  It has four.

|roadman65| was referring to interchanges like this.

Exactly. The Cassaday exchange to K-177.

[Ned Weasel]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

What's weirder is it has two former trumpets that were converted to roundabout interchanges, for who knows what reason.  Exits 202 and 204.  https://goo.gl/maps/bA6Ucaci6ebJBkGJ8

[Strider]

Thank you for answering my question. Much appreciated!

[roadman65]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

What's weirder is it has two former trumpets that were converted to roundabout interchanges, for who knows what reason.  Exits 202 and 204.  https://goo.gl/maps/bA6Ucaci6ebJBkGJ8

The casino south of Wichita is got roundabouts at its KTA interchange also.

[XamotCGC]

It allows for a closed system, where you pay to enter and exit at every interchange. This is opposed to Kentucky's system, where not every exit was tolled and it was possible for some traffic to use sections of the toll road without paying a toll.

Wasn't most of Kentucky's toll interchanges a bowtie?

[Ned Weasel]

The KTA in Kansas has some diamond interchanges, but one toll booth still positioned to collect in all directions.

What's weirder is it has two former trumpets that were converted to roundabout interchanges, for who knows what reason.  Exits 202 and 204.  https://goo.gl/maps/bA6Ucaci6ebJBkGJ8

The casino south of Wichita is got roundabouts at its KTA interchange also.

Yeah, but that one actually makes sense, because they needed a way to connect the interchange to the new casino.  As for Exits 202 and 204, I don't see any reason whatsoever for making that change.

[cpzilliacus]

As toll roads (including ticket-toll roads that charge by the mile) become all-electronic and cashless toll collection, there will be no need for trumpet interchanges, as gantries can be placed between interchanges (as in MD-200) or over the entrance and exit ramps (as in Highway 407 ETR in Ontario).

[roadman65]

Yes, but many will still leave them in place rather then spend millions to replace.  The newer ones will be diamonds or folded diamonds or even parclos cause they are spending anyway.