Busiest "Wrong Way" Interchange

[michravera]

I drove SB I-880 to SB US-101 today and passed at least two "wrong way" interchanges: NB US-101 to SB I-880 and SB US-101 to NB I-880. These are usually pretty busy, but weren't too bad today. I haven't looked up the traffic counts, but I'm not sure that they are registered for the interchanged.

So, my question for the group: "What 'wrong way' interchange gets the most traffic?" If you can do better by counting an intersection that goes through a traffic control, I'm interested as well. 

[TheCatalyst31]

"EB" I-90/94 to WB I-290 and EB I-290 to "WB" I-90/94 in downtown Chicago have to be up there, though that's cheating a little because I-90/94 run north-south through Chicago. In a similar vein, EB I-894 to WB I-94 and vice versa in Milwaukee are the through route for I-43 despite being "wrong way" interchanges on paper. There are probably a few other busy interchanges on the long north-south stretch of I-94 that qualify.

[Dirt Roads]

Totally cheating here, but I-40 East -to- I-440 West in Raleigh racks up 20,000 AADT [eastbound] and 25,000 AADT [westbound].  The former was once called the Beltline Outer Loop and the latter was the Inner Loop, with I-440 originally being posted around the entire "beltstrap".  Even though that's the mainline routing at that corner of the Beltline, the volumes are a mere fraction of the volumes headed to/from I-40 from Joco [south].

[webny99]

Is it safe to assume you're primarily looking for the busiest wrong-way ramps, rather than their interchanges as a whole?

One that's notable although not spectacular: the SB-to-NB movements at the junction of I-390 and I-590 (NY) combine for around 35k AADT.

[CtrlAltDel]

So, my question for the group: "What 'wrong way' interchange gets the most traffic?" If you can do better by counting an intersection that goes through a traffic control, I'm interested as well. 

What is a wrong-way interchange?

[pderocco]

If I understand the meaning correctly (A NB route becoming a SB route, or an EB route becoming a WB route, or vice versa), I-93 and I-95 in Canton MA have a combined AADT of 160K in the two directions (that is, not including counts for I-95 south of there).

[TheHighwayMan3561]

MN has things like:

WB I-94 to EB I-694 (Brooklyn Center) - 13200
EB US 10 to WB TH 610 - 12000
EB TH 610 to WB US 10 - 11000

[gonealookin]

Nevada's candidates for this are few.

The ramp from northbound I-11/US 93/US 95 to southbound I-15 in the downtown Las Vegas "Spaghetti Bowl" shows AADT of 24,900 in 2024.

[Dirt Roads]

Certainly not the busiest, but here is a pair of "wrong-way" interchanges that work in tandem with each other:

I-85 northbound terminus to/from I-95 southbound in Petersburg, Virginia: 5700 ADT (85-to-95) plus 5500 ADT (95-to-85).
I-95 southbound -to- I-295 northbound in South Prince George, Virginia: 1400 ADT (95-to-295) plus 1400 ADT (295-to-95).

[Dirt Roads]

A fascinating one in Lynchburg, Virginia is this interchange between what's now called the Jerry Falwell Parkway (US-29/US-460) and Candler Mountain Road (US-501 northbound).  This one also feels like cheating, since it is the continuation of US-501 northbound from a wrong-way multiplex with US-29 southbound.  But it wasn't always this way.

The ramp from US-29 southbound -to- US-501 northbound carries an amazing 6200 ADT.  VDOT hasn't published data for its reverse counterpart, but I'm pretty sure that it is close.  Even more amazing is that the "opposite" flow (US-29 northbound -to- US-501 northbound) is even higher at 7600 ADT. 

This section of Candler Mountain Road has served as a shortcut between what Lynchburgers called the Lynchburg Bypass and the Lynchburg Expressway since about 1976.  Back then, the movement described above was US-460 westbound and the Lynchburg Bypass ended there until it was extended to US-29 (and posted as VA-224) in 1980.  Even after US-460 completely bypassed Lynchburg in 1988, this zig-zag continued as a main route through Lynchburg (and US-501 was multiplexed onto Candler Mountain Road shortly after). 

Candler Mountain Road northbound carries a mind-boggling 31,000 ADT (westbound) and 41,000 (eastbound) between the two bypasses.  At the most, US-501 only contributes about a quarter of this traffic (perhaps much less, as there is still quite a bit of traffic that stays on Campbell Avenue).  Rather, this is an example of how locals learned how to zig-zig to get around Lynchburg and keep now doing the same thing to get into Lynchburg.

[bing101]

I was thinking MacArthur Maze in Oakland as having that issue where Highways 580 and Highway 80 get that issue. As in to go south on East Highway 580 and West Highway 80 when one goes from Berkeley to Oakland. 

[pianocello]

The ramp from SR 408 WB to I-4 EB in downtown Orlando has 13000 ADT. I can't pinpoint many of the other ramps because the FDOT map is out of date, but I imagine WB I-4 to EB SR 408 movement is similar.

[ski12616]

A couple examples on the Missouri side of the Kansas City area (2024 AADT):
18167 I-35 SB to I-29 NB / 16194 I-29 SB to I-35 NB
13986 I-635 NB to I-29 SB / 13500 I-29 NB to I-635 SB

On the other side of the state, if you want to count I-44 EB becoming I-70 WB in downtown St. Louis and vice versa, that appears to be somewhere in the 25000-35000 range. St. Charles County examples are much lower (around 1,000 or fewer).

[DTComposer]

I would guess the 4-level interchange in Los Angeles would be a contender, since both US-101 and CA-110 are signed north/south.

[Molandfreak]

MN has things like:

WB I-94 to EB I-694 (Brooklyn Center) - 13200
EB US 10 to WB TH 610 - 12000
EB TH 610 to WB US 10 - 11000

How much on I-535 north to I-35 south or vice-versa?

[kphoger]

I'm confused by the OP.  Isn't each of the examples given (NB US-101 → SB I-880 / SB US-101 → NB I-880) handled by a single-lane loop ramp?  Hardly seems either one would be a candidate for busiest.

[michravera]

I'm confused by the OP.  Isn't each of the examples given (NB US-101 → SB I-880 / SB US-101 → NB I-880) handled by a single-lane loop ramp?  Hardly seems either one would be a candidate for busiest.

... but you should see what they do to the traffic trying to use the "natural" movements...

[webny99]

However, most congested ≠ busiest

[jay8g]

South end of I-405 (WA) in Tukwila:

• SB I-405 to NB I-5: 22,000 AADT
• SB I-5 to NB I-405: 30,000 AADT

versus:

• SB I-405 to SB I-5: 20,000 AADT
• NB I-5 to NB I-405: 20,000 AADT

Interesting since it's the end of a loop interstate.

Other locations:
SB US 101 to NB I-5 (Olympia): 33,000
SB I-5 to NB US 101: 32,000
NB I-405 to SB SR 167: 25,000
NB SR 167 to SB I-405: 23,000
SB I-705 to NB I-5: 21,000

[zzcarp]

CDOT doesn't seem like they provide pure ramp volumes, but I'd say the SB I-25 to NB I-225 (and vice-versa) movements may fit the category in Denver. I-25 is 242k AADT north of the interchange and 238k south of the interchange with I-225 having 162k just north of the interchange. One can infer that that traffic is nearly evenly split between the "right-way" and "wrong-way" portions of the interchange with a slight preference to the "wrong-way" movements.

[JayhawkCO]

CDOT doesn't seem like they provide pure ramp volumes, but I'd say the SB I-25 to NB I-225 (and vice-versa) movements may fit the category in Denver. I-25 is 242k AADT north of the interchange and 238k south of the interchange with I-225 having 162k just north of the interchange. One can infer that that traffic is nearly evenly split between the "right-way" and "wrong-way" portions of the interchange with a slight preference to the "wrong-way" movements.

I was just trying to think of the best way to calculate the data for this exact interchange. Nearby, I would also think NB CO83->SB I-225 and vice versa has to be up there too.

[Dirt Roads]

South end of I-405 (WA) in Tukwila:

• SB I-405 to NB I-5: 22,000 AADT
• SB I-5 to NB I-405: 30,000 AADT

versus:

• SB I-405 to SB I-5: 20,000 AADT
• NB I-5 to NB I-405: 20,000 AADT

Interesting since it's the end of a loop interstate.

CDOT doesn't seem like they provide pure ramp volumes, but I'd say the SB I-25 to NB I-225 (and vice-versa) movements may fit the category in Denver. I-25 is 242k AADT north of the interchange and 238k south of the interchange with I-225 having 162k just north of the interchange. One can infer that that traffic is nearly evenly split between the "right-way" and "wrong-way" portions of the interchange with a slight preference to the "wrong-way" movements.

Just looking at these two posts makes me wonder if suburbia in many cities has reached a density level whereby more folks are driving around an "outer loop" of a city to get into the city, than the number of vehicles (often trucks) using that same "outer loop" to bypass the city.  If so, we ought to have a lot more high volume "wrong way" interchanges (not discounting that the same dynamic *also* increases the volume of "right way" interchanges on the same "outer loop".  Stay tuned.

[webny99]

Just looking at these two posts makes me wonder if suburbia in many cities has reached a density level whereby more folks are driving around an "outer loop" of a city to get into the city, than the number of vehicles (often trucks) using that same "outer loop" to bypass the city. 

Frankly I wouldn't be surprised if this has always been the case for most beltways.

[zzcarp]

CDOT doesn't seem like they provide pure ramp volumes, but I'd say the SB I-25 to NB I-225 (and vice-versa) movements may fit the category in Denver. I-25 is 242k AADT north of the interchange and 238k south of the interchange with I-225 having 162k just north of the interchange. One can infer that that traffic is nearly evenly split between the "right-way" and "wrong-way" portions of the interchange with a slight preference to the "wrong-way" movements.

I was just trying to think of the best way to calculate the data for this exact interchange. Nearby, I would also think NB CO83->SB I-225 and vice versa has to be up there too.

Yeah, I pulled that data too, though that's a little more complicated. CO 83 has about 50k AADT just north of the park and ride and I-225 versus 83k AADT south of I-225 (north of the dam road) and drops to 72k at CO 83 and Hampden. I-225 has 172k south of Parker Road and 150k north of Parker Road. That does indicate a significant movement from NB I-225 to SB CO 83 and the reverse, at least 20k more vehicles taking the "wrong-way" movements. It's too many variables for me to drill down any further.

Another one I was thinking of was WB C-470 to EB I-70/ WB I-70 to EB C-470 near Golden. C-470 has 84k AADT east of Alameda (the next exit east of I-70) and 29k west of I-70. I-70 has 123k east of C-470 and 90k west of it. The math again doesn't add up entirely, but it seems like at least 30k cars make the "wrong-way" movements daily.

Just looking at these two posts makes me wonder if suburbia in many cities has reached a density level whereby more folks are driving around an "outer loop" of a city to get into the city, than the number of vehicles (often trucks) using that same "outer loop" to bypass the city.  If so, we ought to have a lot more high volume "wrong way" interchanges (not discounting that the same dynamic *also* increases the volume of "right way" interchanges on the same "outer loop".  Stay tuned.

I think that makes sense, especially when the loops have signed directions that may not exactly reflect their cardinal directions at the interchanges.

[Dirt Roads]

Virginia has a few examples of wrong-way interchanges from the "outer loop" that might meet this criteria.  Two of the big ones that come to mind (Capital Beltway Outer Loop -to- I-395 Shirley northbound, and Capital Beltway Inner Loop -to- I-395 Shirley northbound) don't have any data.

Other interchanges on the Capital Beltway in Virginia that this subthread covers:

• I-495 outer loop (from Maryland) -to- George Washington Parkway eastbound (48,100 ADT calc) and GWP westbound -to- I-495 inner loop (22,000 ADT)
• I-495 inner loop -to- VA-7 Leesburg Pike southbound (5,300 ADT) and VA-7 westbound -to- I-495 outer loop (4,500 ADT)

The other ones are on the so-called Hampton Roads Beltway.  The two which meet the OP criteria don't carry the majority of the "interchange" traffic:

• I-64 eastbound -to- I-564 westbound (8,400 ADT) and I-564 eastbound -to- I-64 westbound (6,800 ADT)
• I-64 "eastbound" -to- I-264 westbound (13,000 ADT) and I-264 eastbound -to- I-64 westbound (12,000 ADT); ergo more traffic exiting to Virginia Beach

Other interchanges on the HRB that this subthread covers:

• I-64 "eastbound" (clockwise) -to- Indian River Road northwestward (5,800 ADT)
• I-64 "eastbound" (clockwise) -to- Greenbrier Parkway northbound (5,700 ADT)
• I-64 "eastbound" (clockwise) -to- I-464 northbound (11,000 ADT) and I-464 southbound -to- I-64 counterclockwise (11,000 ADT)
• I-664 southbound (counterclockwise) -to- I-264 eastbound (11,000 ADT) and I-264 westbound -to- I-664 northbound (11,000 ADT)
• I-664 southbound (counterclockwise) -to- US-58/US-460 eastbound (3,000 ADT)
• I-664 southbound (counterclockwise) -to- VA-337 Portsmouth Blvd. eastbound (4,000 ADT)
• Taylor Road southbound (Pughsville Road westbound) -to- I-664 northbound (clockwise) (4,500 ADT)**

Heading up to Richmond, I found one that meets the OP criteria:

• VA-10 Iron Bridge Road southbound -to- VA-288 northbound (4,300 ADT)***

We also have a few in Richmond that fall into the "other category":

• I-295 "northbound" -to- I-64 eastbound (13,000 ADT) and I-64 westbound -to- I-295 "southbound" (16,000 ADT)
• VA-288 southbound -to- US-360 Hull Street Road eastbound (3,600 ADT) and US-360 westbound -to- VA-288 northbound (4,300 ADT)
• Lopsided??? VA-895 Powhatan Parkway (toll) westbound -to Laburnum Avenue "westbound" (120 ADT), but Laburnum Avenue "eastbound" -to- VA-895 eastbound (4,200 ADT)****
• US-1/US-301 southbound -to- VA-150 Chippenham Parkway northbound (3,500 ADT)***
• US-360 Hull Street Road westbound -to- VA-150 Chippenham Parkway northbound (3,500 ADT)****
• Lopsided, Part Deux:  VA-150 Chippenham Parkway southbound -to- US-60 Midlothian Turnpike (13,000 ADT) and US-60 westbound -to- VA-150 northbound (4,400 ADT)
• VA-150 Chippenham Parkway southbound -to- VA-76 Powhite Parkway (toll) "eastbound" (5,000 ADT) and Powhite Parkway westbound -to- the Chippenham northbound (3,400 ADT)

* The topology of the Bowers Hill interchange overlaps I-664 traffic with US-58/US-460/US-13 traffic in both directions, greatly increasing the ADT on the HRB approaching this interchange.
** The southbound exit is for both directions of Pughsville Road.
*** No data for the opposite movement.
**** This one coulda/shoulda/woulda meet the OP criteria, except for the lopsided opposite traffic.
***** The southbound exit is for both directions of US-360 Hull Street Road.