What's the biggest interchange in your state? Is it the best designed?

[OCGuy81]

I'm not sure what the biggest interchange in Oregon is, maybe where 405 meets 5 in Portland (the south junction) but it's far from the best designed. Left exit for 405 from 5 SB, a ramp to OR 43 that's narrow and comes up quick.

Best designed one I might have seen in this state is I-5 at OR-569 near Eugene. Nice flyovers and seems to manage flow well.

[SkyPesos]

I-71/75 in Cincinnati for Ohio, and no, it's not well designed. There's a reason why this interchange made top 10 for worst truck bottlenecks for the past few years. It will most likely get rebuilt if the Brent Spence Bridge gets replaced

[silverback1065]

  Maybe the north split in indiana? (65/70) it's being rebuilt this year though.

[US 89]

For Utah the answer is by far the Spaghetti Bowl (I-15/I-80/SR 201/various local streets). Nothing else comes close.

It was entirely rebuilt in 2001 for the Olympics the next year, so it flows pretty well. I only have a couple minor issues with it:

1) It lacks a direct connection from the SR 201 freeway to 2100 South - that movement involves detouring through the 900 West interchange on 201.
2) It lacks a ramp from 2100 South to I-80 east, instead requiring travelers to spend an extra mile on surface streets to reach the I-80 interchange on State Street (US 89).

[cwf1701]

For Michigan, there is 2 large ones within a few miles:

(1) the I-96/I-275/I-696/M-5 interchange. This interchange was more ad hock over the years.

(2) The I-696/M-10/US-24 interchange.

[Big John]

There are 2 big interchanges by Milwaukee -- Marquette (I-43/94/794) and Zoo (I-41/94/894, US 45).  The Marquette was reconstructed 10 years ago and the Zoo is in its reconstruction, s they are good to ride on.

[coldshoulder]

I-71/75 in Cincinnati for Ohio, and no, it's not well designed. There's a reason why this interchange made top 10 for worst truck bottlenecks for the past few years. It will most likely get rebuilt if the Brent Spence Bridge gets replaced

I recall reading once that the I-70 / I-77 interchange near Cambridge in southeastern Ohio was the largest in the state, as far as total acreage consumed by the interchange footprint.  It's a relatively simple and symmetrical layout with two loop ramps from I-70 and two offsetting left exit ramps from I-77:

https://goo.gl/maps/CYhf7y8iXKGWEggW9

[thspfc]

The biggest in terms of ramps is the Marquette. The biggest in terms of traffic volume is the Zoo (supposedly; either way it's very close). WISDOT loves big interchanges. The vast majority of them have been built within the last decade, including several along the I-41 corridor: Zoo in Milwaukee, US-45 in Oshkosh, US-10/WI-441 in Appleton, WI-29/Shawano Ave in Green Bay, and I-41/I-43 in Green Bay. As for best designed, both the Zoo and Marquette are very impressive, but I have to give it to the Marquette because of the space constraints, with it being in downtown while the Zoo is further out. Hopefully the Stadium Interchange (I-94 and Miller Park Way) gets a makeover soon.

[thspfc]

Maybe the north split in indiana? (65/70) it's being rebuilt this year though.

I think it's one of the I-70/I-465 interchanges.

[TheHighwayMan3561]

Minnesota's is probably 35W/94/MN 55 which involves a winding mess of ramps between the three highways plus on-ramps and off-ramps to and from city streets. Other than there's no SB 35W-EB 94 direct movement (that's handled by Washington Ave and Cedar Ave), I've never found anything wrong with it.

[thspfc]

There are 2 big interchanges by Milwaukee -- Marquette (I-43/94/794) and Zoo (I-41/94/894, US 45).  The Marquette was reconstructed 10 years ago and the Zoo is in its reconstruction, s they are good to ride on.

Have you been down to Milwaukee recently? Zoo has been finished for about 3 years now. It's really nice. One of the best in the country for sure.

[tdindy88]

Maybe the north split in indiana? (65/70) it's being rebuilt this year though.

I think it's one of the I-70/I-465 interchanges.

The eastside one perhaps. They're both about the same size. Actually the current construction plans for the North Split might make it a tad smaller. One of the ideas of its redesign is to make it a little more simpler and efficient. It's large size was partially due to uneeded ramps that were never utilized. I would also wager that the upcoming redesign of the northeast side I-465/I-69 interchange might be among the biggest when completed.

One further note, I wonder how the I-65/Borman Expressway (80/94) interchange is size wise?

[SkyPesos]

I-71/75 in Cincinnati for Ohio, and no, it's not well designed. There's a reason why this interchange made top 10 for worst truck bottlenecks for the past few years. It will most likely get rebuilt if the Brent Spence Bridge gets replaced

I recall reading once that the I-70 / I-77 interchange near Cambridge in southeastern Ohio was the largest in the state, as far as total acreage consumed by the interchange footprint.  It's a relatively simple and symmetrical layout with two loop ramps from I-70 and two offsetting left exit ramps from I-77:

https://goo.gl/maps/CYhf7y8iXKGWEggW9

Totally skipped over that one because of its simplicity. I was debating between I-71/75 and I-71/670, eventually went with 71/75. But I like the design of that interchange.

[Big John]

There are 2 big interchanges by Milwaukee -- Marquette (I-43/94/794) and Zoo (I-41/94/894, US 45).  The Marquette was reconstructed 10 years ago and the Zoo is in its reconstruction, s they are good to ride on.

Have you been down to Milwaukee recently? Zoo has been finished for about 3 years now. It's really nice. One of the best in the country for sure.

Sorry about that.  i have its schedule mixed up. 

[jmacswimmer]

Maryland: Once fully built out it'll be the northeast I-95/I-695 interchange (currently a 4-level stack, with direct flyovers to/from the I-95 ETL's to be added later), but for the moment it might be a close contest between the aforementioned interchange, I-70/I-695, I-270/I-370, I-95/I-495 College Park, I-95/I-495/I-595/US 50, & I-95/I-495/I-295/Nat'l Harbor.  If I-270/I-495 was one interchange instead of 3 partial interchanges spread out from each other, it would probably be in the running too.  Also worth noting is the 3 closely-spaced interchanges in Frederick where I-70, I-270, US 15, US 40, & US 340 all meet - none of them are too large on their own, but when viewed as one big interchange system I think it's rather impressive.

All are fairly well designed, with a couple exceptions:

-The ramp from I-495 EB to I-95 NB in College Park has a fairly sharp curve, and the last half-mile on I-495 leading up to the ramp has quite a bit of weaving as everyone tries to squeeze over for the exit.
-The I-70/I-695 stack was well-designed for its intended use had I-70 been completed to I-95, but we all know what happened there and now the ramps leading to/from the west are heavily utilized (none more so than I-70 EB to I-695 NB) while to/from the east is underutilized.
-I-70 WB thru the Frederick interchanges has an unusual lane configuration that likely contributes to the recurring congestion there - enters with 3 lanes + an aux lane from exit 54; this aux lane + the right 2 lanes gradually depart at exits 53 & 52 while 2 lanes add on the left from I-270, the left of which ends.  Which leaves 70 with 2 lanes leaving Frederick.  Got all that?

1995hoo, any thoughts on what the biggest interchange might be across the Potomac in your state?   

There are 2 big interchanges by Milwaukee -- Marquette (I-43/94/794) and Zoo (I-41/94/894, US 45).  The Marquette was reconstructed 10 years ago and the Zoo is in its reconstruction, s they are good to ride on.

Have you been down to Milwaukee recently? Zoo has been finished for about 3 years now. It's really nice. One of the best in the country for sure.

Speaking of the Zoo, I saw that this just happened the other day - the driver survived, fortunately.

https://www.youtube.com/watch?v=VsUw5UZEJ4g

[NWI_Irish96]

Maybe the north split in indiana? (65/70) it's being rebuilt this year though.

I think it's one of the I-70/I-465 interchanges.

The eastside one perhaps. They're both about the same size. Actually the current construction plans for the North Split might make it a tad smaller. One of the ideas of its redesign is to make it a little more simpler and efficient. It's large size was partially due to uneeded ramps that were never utilized. I would also wager that the upcoming redesign of the northeast side I-465/I-69 interchange might be among the biggest when completed.

One further note, I wonder how the I-65/Borman Expressway (80/94) interchange is size wise?

The I-65/Borman interchange is pretty expansive as the NB->WB and EB->SB ramps are a good 1/2 mile or so away from the rest of the interchange.

[JayhawkCO]

Largest here is obviously the I-25/I-70 interchange (the Mousetrap).  It's fine, but EB 70 -> SB I-25 always clogs up pretty well on the weekends with people coming back from the mountains.

Chris

[CoreySamson]

I don't even know where to begin in Texas. All the big interchanges are interchangeable stacks. I can say that they are well designed.

[STLmapboy]

For MO, I'd say KC's Alphabet loop. Not really a single interchange, but lots of them contained therein. And no, it's not particularly well designed.

[TheGrassGuy]

Crazy irregular interchanges in NJ:
- US 1-9/Newark Airport/NJ 81 (indirectly), US 1-9/US 22/NJ 21/I-78/Newark Airport Connector, US 1-9/I-78, and I-78/I-95 (Newark Airport spaghetti bowl)
- I-95/US 46 (Ridgefield)
- I-95/US 1-9/US 46/NJ 4/NJ 67 (indirectly)/PIP (indirectly) (Fort Lee)
- I-76/I-676/US 130 (indirectly)/NJ 168 (indirectly) (Camden)
- US 30/US 130/NJ 38/NJ 70 (indirectly) (Pennsauken)

[frankenroad]

I-71/75 in Cincinnati for Ohio, and no, it's not well designed. There's a reason why this interchange made top 10 for worst truck bottlenecks for the past few years. It will most likely get rebuilt if the Brent Spence Bridge gets replaced

I recall reading once that the I-70 / I-77 interchange near Cambridge in southeastern Ohio was the largest in the state, as far as total acreage consumed by the interchange footprint.  It's a relatively simple and symmetrical layout with two loop ramps from I-70 and two offsetting left exit ramps from I-77:

https://goo.gl/maps/CYhf7y8iXKGWEggW9

I remember it being touted as largest in the country.  It was featured on an Ohio State Highway map cover, probably sometime in the 1970s.  I don't know if it still is, but looking at the Google map, I would guess it has been surpassed.

[SkyPesos]

Largest here is obviously the I-25/I-70 interchange (the Mousetrap).  It's fine, but EB 70 -> SB I-25 always clogs up pretty well on the weekends with people coming back from the mountains.

Chris

With the EB 70 to SB 25 movement, is the US 6 freeway also used as an alternative to that movement? I would be surprised if everyone relied on that one ramp movement, but not a lot of people use US 6 to get from EB 70 to SB 25.

[TheStranger]

The East Los Angeles Interchange, both in volume and sheer size.

Looking at it and the San Bernardino Split just north of there, part of me wonders if the simplest thing would have been to have the Golden State Freeway end right at the San Bernardino Split, and have a simpler interchange for the Pomona/Santa Monica with the Santa Ana instead.  A rail yard north of the Split (and west of I-5/Golden State Freeway) is what possibly precluded this.

In many ways the eventual East Los Angeles configuration + the current route designation choices in the area were adaptive towards existing roads (Santa Ana Freeway, San Bernardino Freeway) rather than the most logical, particularly I-10's jog from the Santa Monica to the Golden State and then San Bernardino Freeways.

[JayhawkCO]

Largest here is obviously the I-25/I-70 interchange (the Mousetrap).  It's fine, but EB 70 -> SB I-25 always clogs up pretty well on the weekends with people coming back from the mountains.

Chris

With the EB 70 to SB 25 movement, is the US 6 freeway also used as an alternative to that movement? I would be surprised if everyone relied on that one ramp movement, but not a lot of people use US 6 to get from EB 70 to SB 25.

I always take US6 myself, but I'm sure there is a good segment of the populace that isn't using Google Maps that just know that I-70 and I-25 connect and they need to get onto I-25 south.  (The US6 WB->I-25 SB traffic also sucks on the weekends.)

I've always been amazed by the amount of people who don't know what "shape" the highways take in their city.  I'm sure my wife has no idea why we take US6 west when we're going to the mountains instead of I-70.

Chris

[webny99]

How are we defining "biggest" interchange?

There's a lot of different ways I can think of, from the one that covers the most land area, to the one with the most road miles, to the one with the highest overall traffic volumes.