"Duplicate" Ramps

[GaryA]

Camarillo, CA - Carmen Dr to US-101 South. There's an entry ramp off Carmen and an entry ramp off Ventura Blvd just west of the In-N-Out. If you make a mistake of turning left onto Carmen from Ventura and meant to get on the freeway, you have a second chance:
https://www.google.com/maps/@34.2171279,-11
9.0512296,1074m/data=!3m1!1e3?entry=ttu

Ventura, CA - Victoria Ave to US-101 South. Entry ramp off Valentine Rd (serving southbound Victoria Ave traffic) and entry ramp off Victoria Ave (serving northbound Victoria Ave traffic). There's a median separating NB/SB traffic at the Victoria ramp, and there is typically a lot of traffic on this street, so I assume that's why there are two entries.
https://www.google.com/maps/@34.2516827,-119.2123562,1082m/data=!3m1!1e3?entry=ttu

The US-101/Seaward Ave interchange in Ventura is set up very similarly to the Carmen Dr. one -- if you're on Harbor Blvd (which parallels the freeway), you can turn directly into one onramp, or turn onto Seaward and then onto another onramp.
https://maps.app.goo.gl/GWtUEmUbTHzjwX577

[1995hoo]

Southern end of Ontario 416 at ON-401. My sat-nav sent me around the longer route shown on the map via ON-16 and I followed it just to see if I could discern any reason why it sent me that way (I could not).

[SectorZ]

I-95 S/B in Newton MA at MA 16. There are directional east/west A/B ramps, but you can go east or west from both. The reason being is that both ramps merge into roadways that bring you to a full intersection, so you can make both maneuvers but it is certainly optimized to follow the signed directional ramp since you can use a small slip ramp that is subject to a yield sign and not the traffic signal.

Map of area, https://maps.app.goo.gl/axt2WtzbwhKcJfRWA
GSV of intersection, https://maps.app.goo.gl/q84qcKLbXfBwXyQi9

[Dirt Roads]

Northbound US 119 to eastbound I-64 just prior to the Kanawha River crossing in Charleston, WV. There's a flyover that exits to the right as well as a left turn. Both merge on the ramp.

https://maps.app.goo.gl/6FEYPRq5qV94RGYw6

My mind originally thought of the two US-119 onramps to I-64 westbound on the other side of the Fort Hill Bridge, but they didn't seem to qualify.  After second thought (and many other posts), I'm adding this to the list.  Of course, the main reason for two separate exits is to connect the two major one-way pairs (Virginia Street/Randolph Street and US-60 Lee Street/Washington Street).  [Note that Quarrier Street in Downtown becomes Randolph Street on the West Side].

Similarly, there are two corresponding [northbound] offramps here, but only one of them is actually signed for US-119 (Exit 58B).  Pennsylvania Avenue northbound is posted as US-119 north of Exit 58B, but locals headed for US-119 northbound (which Bigley Avenue, a short bypass of "Penna") actually take Exit 58C to avoid the extra traffic signals at Virginia and Randolph. 

[webny99]

Southern end of Ontario 416 at ON-401. My sat-nav sent me around the longer route shown on the map via ON-16 and I followed it just to see if I could discern any reason why it sent me that way (I could not).

I would have thought sticking to ON 416 would have given you a greater likelihood of finding out why the GPS disliked that route (accident, constrution, etc).

[1995hoo]

Southern end of Ontario 416 at ON-401. My sat-nav sent me around the longer route shown on the map via ON-16 and I followed it just to see if I could discern any reason why it sent me that way (I could not).

I would have thought sticking to ON 416 would have given you a greater likelihood of finding out why the GPS disliked that route (accident, constrution, etc).

Mine would not have been able to account for accident, construction, etc., because that feature didn't exist at the time. (Actually, it still can't account for that stuff, as I still drive the same car and Acura stopped offering software updates for the navigation system. They'd rather I buy a new car.)

[MikeTheActuary]

MS302 eastbound used to have two options to go northbound on I-55/I-69, but it looks like updates in 2018-2019 have since eliminated one option.

2014 Streetview: https://www.google.com/maps/@34.9624917,-89.9985923,3a,49.4y,85.45h,84.42t/data=!3m7!1e1!3m5!1slv3Fzugfk8W0rfSn1Zbs9A!2e0!5s20140501T000000!7i13312!8i6656?entry=ttu

2022 Streetview:
https://www.google.com/maps/@34.9624408,-89.9985692,3a,75y,85.45h,84.42t/data=!3m7!1e1!3m5!1sursEx_TRPtBL4IrYCKtkRg!2e0!5s20220601T000000!7i16384!8i8192?entry=ttu


Also in the Memphis area, traffic going westbound on US78 has two signed options to go westbound on I-240 at the eastern interchange:
https://www.google.com/maps/@35.0813718,-89.9568011,1240m/data=!3m1!1e3?entry=ttu

There are two options for traffic on eastbound US78 to access I-240 in either direction at that interchange, but only one set of those options is signed.

[jp the roadgeek]

A couple in the Hartford, CT area

I-84 West to I-384 East:  Direct is Exit 59.  Can also be accessed from the Exit 62-60 c/d road.

US 5/CT 15 South to I-91 South:  Direct is exit 86, but it can also be accessed from the Exit 87 (Airport Rd/Brainard Rd) offramp. 

And then there's the whole NY 120A duplication at the CT/NY state line where the Hutch becomes the Merritt.   Each DOT built an exit ramp to its side of the border.  Before NYSDOT renumbered the exits on the HRP, the exits used to jump from 30 back to 27 when crossing the border; now they jump from 19 to 27. 

[Occidental Tourist]

Little Rock has a couple at one interchange.  At the I-430/I-630 interchange in West Little Rock, a full cloverleaf interchange had flyover ramps added for several of the movements, but they kept the cloverleaf ramps as well, mostly for access to and from local roads immediately adjacent to the interchange.  But there's no barrier preventing a motorist from skipping the flyover and using the cloverleaf to change freeways if they wish.

[Occidental Tourist]

Camarillo, CA - Carmen Dr to US-101 South. There's an entry ramp off Carmen and an entry ramp off Ventura Blvd just west of the In-N-Out. If you make a mistake of turning left onto Carmen from Ventura and meant to get on the freeway, you have a second chance:
https://www.google.com/maps/@34.2171279,-11
9.0512296,1074m/data=!3m1!1e3?entry=ttu

Ventura, CA - Victoria Ave to US-101 South. Entry ramp off Valentine Rd (serving southbound Victoria Ave traffic) and entry ramp off Victoria Ave (serving northbound Victoria Ave traffic). There's a median separating NB/SB traffic at the Victoria ramp, and there is typically a lot of traffic on this street, so I assume that's why there are two entries.
https://www.google.com/maps/@34.2516827,-119.2123562,1082m/data=!3m1!1e3?entry=ttu

The US-101/Seaward Ave interchange in Ventura is set up very similarly to the Carmen Dr. one -- if you're on Harbor Blvd (which parallels the freeway), you can turn directly into one onramp, or turn onto Seaward and then onto another onramp.
https://maps.app.goo.gl/GWtUEmUbTHzjwX577

The Chapman Avenue eastbound exit off the 55 Freeway in Orange sort of has duplicate ramps.  When they widened the freeway about three decades ago, they added a bypass exit ramp south of the 22 to 55 north ramp to allow cars exiting to Chapman Avenue east to avoid traffic transitioning from the 22 Freeway by going to the right of the transition ramp.  However, there are no barriers to prevent you from skipping the bypass exit and moving over from the mainline to exit at Chapman once you pass the 22 transition ramp.

A few years ago they installed a similar setup for 91 westbound traffic at the 55 exiting to Tustin Avenue.  There's a bypass exit before the transition ramp from the 55 north to the 91 west, but you can also wait until after the transition ramp merges onto the 91 to move over and exit at Tustin.

[bzakharin]

I-295 North in New Jersey has two consecutive exits to I-76 (26 and 27). This dates back to before the ongoing construction of the I-295/I-76/NJ 42 interchange, when I-76 had express and local lanes, and there will only be one exit once construction is done. US 22 West has two exits to I-287 North, one direct and one via US 202/206. Likewise, I-287 South has a direct exit to US 22 East, and one via US 202/206. The reason, I would assume, is to give better access to businesses on US 22 to traffic on I-287

[roadman65]

I-295 North in New Jersey has two consecutive exits to I-76 (26 and 27). This dates back to before the ongoing construction of the I-295/I-76/NJ 42 interchange, when I-76 had express and local lanes, and there will only be one exit once construction is done. US 22 West has two exits to I-287 North, one direct and one via US 202/206. Likewise, I-287 South has a direct exit to US 22 East, and one via US 202/206. The reason, I would assume, is to give better access to businesses on US 22 to traffic on I-287

Originally the two ramps had purpose. There used to be an express/ local set up on I-76. So one was the express and the other was to the local.

In Newark, US 1 & 9 SB have two consecutive exits for I-78 EB. Don't know why, but it does help those patrons of the Couryard by Marriot as the hotel is between the two exits as they can access I-78 EB without having to double back. However I don't think NJDOT had the hotel guests in mind when creating those ramps.

[bzakharin]

I-295 North in New Jersey has two consecutive exits to I-76 (26 and 27). This dates back to before the ongoing construction of the I-295/I-76/NJ 42 interchange, when I-76 had express and local lanes, and there will only be one exit once construction is done. US 22 West has two exits to I-287 North, one direct and one via US 202/206. Likewise, I-287 South has a direct exit to US 22 East, and one via US 202/206. The reason, I would assume, is to give better access to businesses on US 22 to traffic on I-287

Originally the two ramps had purpose. There used to be an express/ local set up on I-76. So one was the express and the other was to the local.

It's right there in my comment

[bzakharin]

Another example in NJ is where the Atlantic City Expressway Westbound terminates at NJ 42. Right before the merge, which is from the left, there is an exit which merges onto NJ 42 from the right, whose only purpose is to allow access from the Atlantic City Expressway to Exit 7 on NJ 42 without weaving.

[Rothman]

I-295 North in New Jersey has two consecutive exits to I-76 (26 and 27). This dates back to before the ongoing construction of the I-295/I-76/NJ 42 interchange, when I-76 had express and local lanes, and there will only be one exit once construction is done. US 22 West has two exits to I-287 North, one direct and one via US 202/206. Likewise, I-287 South has a direct exit to US 22 East, and one via US 202/206. The reason, I would assume, is to give better access to businesses on US 22 to traffic on I-287

Originally the two ramps had purpose. There used to be an express/ local set up on I-76. So one was the express and the other was to the local.

It's right there in my comment

Yep, he does that sort of thing.

[cwf1701]

I-696 (east) at I-94 (west) There is a movement from EB I-696 to WB I-94 via the 11 Mile road exit from I-696. From the ramp from I-696, you follow 11 Mile road 1/4 mile to the WB I-94 onramp from 11 Mile road https://www.google.com/maps/search/11+mile+and+i+94+roseville+Mi/@42.4946618,-82.9253376,16.13z?entry=ttu

[sbeaver44]

US 340 has two ways to continue on US 15 North at its northern end in Frederick.  You can take the right-hand loop ramp or the left at the traffic light.

Not sure if this counts but I often do it and have seen others do it.  While on South I-83/East US 322 in Harrisburg, approaching the Eisenhower, you can use US 322 to the exit for Paxton St to merge back onto 83 South without having to stop.  This eliminates the left hand merge with I-283's ramp and then US 322 West's ramp.

[webny99]

Not sure if this counts but I often do it and have seen others do it.  While on South I-83/East US 322 in Harrisburg, approaching the Eisenhower, you can use US 322 to the exit for Paxton St to merge back onto 83 South without having to stop.  This eliminates the left hand merge with I-283's ramp and then US 322 West's ramp.

I would certainly say it fits in spirit, but it's pretty much two different interchanges so it's interesting that it can be done southbound but not northbound.

[lordsutch]

MS302 eastbound used to have two options to go northbound on I-55/I-69, but it looks like updates in 2018-2019 have since eliminated one option.

2014 Streetview: https://www.google.com/maps/@34.9624917,-89.9985923,3a,49.4y,85.45h,84.42t/data=!3m7!1e1!3m5!1slv3Fzugfk8W0rfSn1Zbs9A!2e0!5s20140501T000000!7i13312!8i6656?entry=ttu

2022 Streetview:
https://www.google.com/maps/@34.9624408,-89.9985692,3a,75y,85.45h,84.42t/data=!3m7!1e1!3m5!1sursEx_TRPtBL4IrYCKtkRg!2e0!5s20220601T000000!7i16384!8i8192?entry=ttu

You used to also be able to do the same thing from WB MS 302 to SB I-55/69. It appears MS 302/Goodman Road got a much-needed third through lane in each direction to eliminate those turn options.

The C/D road setup and parallel roadways for I-85 and I-285 in southwest Fulton County give you at least two options for several movements, although only one is signed. For example, you can get on I-85 north from I-285 south either via the signed flyover ramp or via the ramp signed for GA 279/Old National Highway, which puts you on a C/D road that will give you access to I-85 north. You can also use the same C/D road to get from I-85 north to I-285 east, rather than using the direct ramp. You can do similar things westbound from I-285 or southbound from I-85.

[ErmineNotyours]

599 south to south I-5.  Two ramps are provided, a normal right entrance and a left entrance to better access the left I-405 ramp.

I-405 NB to SR 520 EB in Bellevue.  The ramp splits, with the left fork signed for "124th Ave NE."  That actually joins SR 520, in the right lane, just before that right lane becomes an exit for 124th Ave NE.  Then, the right fork - which was signed for "SR 520 East" - joins 520, also in the right lane.

Google recommends joining 520 immediately, though it would be better to take advantage of the expensive new capacity provided by the state.

[Dirt Roads]

US 340 has two ways to continue on US 15 North at its northern end in Frederick.  You can take the right-hand loop ramp or the left at the traffic light.

This reminds me of one of my most bizarre driving moments, when I realized that the two through lanes at the east end of US-340 were backed up heading into Frederick on Jefferson Street.  When there was a gap in traffic in the left through lane, I was able to sneak over to the left turn lane to catch US-15 during the traffic signal cycle.  When somebody tried to follow me, they had to wait for another gap and got caught at the traffic light.

[webny99]

Referred to in another thread, I-10 WB has a duplicate ramp to I-20:

It's in Texas, but not a normal "Texas U-Turn" -- traffic on I-20 that wants to go EB on I-10 must merge into the I-10 WB mainline and take a left exit that U-turns onto I-10 EB before the I-20 split.  (Traffic from I-10 WB to I-20 could also follow this path, but they do have a direct ramp.)  https://maps.app.goo.gl/w7waAcSzSYJb2YJt6

What's interesting here is that they installed a separate ramp for I-10 WB to I-20 EB when that movement could also be made from the U-turn ramp ...