Can TOTSOs involve highway concurrencies?

[Techknow]

In California, there are well known TOTSOs, all of which involve exits to routes that begin if one chooses to stay on the road:

• Intersection of I-5 N and I-580 W
• Intersection of I-80 N and US 50 E at West Sacramento
• Intersection of I-5 N and CA 99 N at Wheeler Ridge

Is it possible that this applies to concurrent routes or signed concurrencies as well or does this convention only apply to intersections of two highways (whether one highway starts or comes from another direction to intersect)?

I think it makes sense because if you're on a highway with a signed concurrency and you have to exit in order to stay on the second highway, then that's TOTSO

[ran4sh]

There's an engineering difference between an exit and a mainline split, I would say that a properly engineered split shouldn't really count as TOTSO, but exits certainly count regardless of any concurrencies present.

I-5 and I-580 is not a TOTSO. I-5 and CA-99 could be considered a TOTSO but I would say it is not.

[SkyPesos]

I forgot interstate-interstate concurrencies are rare in California...

But yes, it can apply to concurrencies as well, most notably when an interstate number enters or leaves a turnpike, like I-70 and PA Turnpike at New Stanton and Breezewood.

[pderocco]

Is I-215 in Riverside, CA a TOTSO? Sure feels like you're taking an exit, in either direction. One leg is multiplexed with CA-60.

Then there's I-210 in Pasadena.

And I-10 northeast of downtown LA, where one leg is shared with I-5.

Another concurrency TOTSO occurs between CA-2 and I-210 in La Canada Flintridge.

Back where I grew up, I-95 has two TOTSOs where it enters and leaves MA-128.

Also US-3 and MA-128/I-95 in Burlington.

[Dirt Roads]

The new interchange of the US-70 Freeway in East Durham with I-885 certainly qualifies as a TOTSO.  I-885 then runs concurrently with US-70 up to I-85, where I-885 ends and I-70 continues.  Which also might be considered a TOTSO for US-70, which is all freeway for more than 11 miles (now almost entirely concurrent with I-85 and I-885).

[Techknow]

There's an engineering difference between an exit and a mainline split, I would say that a properly engineered split shouldn't really count as TOTSO, but exits certainly count regardless of any concurrencies present.

Thanks for bringing this up. I'm not looking to stretch the term in a literal sense. Freeway/highway splits happen a lot in 2-dimensionial space. I agree the I-5/I-580 interchange shouldn't be considered a TOTSO now because the mainline splits in such a way that I-5 doesn't require an overpass/underpass to continue north.

Moreover as pderocco mentioned, I-215 feels like exiting the freeway. Here I don't think it feels like that at all. I forgot about the interchange with CA 99 and 152 because I never thought of it as a TOTSO. GSV linked for convenience The mainline here splits the same way as I-5 does with I-580 because both splits involve left freeway exits.

I forgot interstate-interstate concurrencies are rare in California...

Yep there's just one in CA, I-80 and I-580 in Berkeley and it's a wrong way concurrency too! TOTSOs are most common with freeways but it could happen with any type of route.

Is I-215 in Riverside, CA a TOTSO? Sure feels like you're taking an exit, in either direction. One leg is multiplexed with CA-60.

Then there's I-210 in Pasadena.

And I-10 northeast of downtown LA, where one leg is shared with I-5.

Another concurrency TOTSO occurs between CA-2 and I-210 in La Canada Flintridge.

Back where I grew up, I-95 has two TOTSOs where it enters and leaves MA-128.

Also US-3 and MA-128/I-95 in Burlington.

Yeah those are great examples of roads that feel like exiting one road to get to another but staying in the same route. The routing of I-215 in Riverside is interesting to say the least. Actually I once clinched I-215 as a passenger on a road trip from SF to San Diego but it was 6 years ago and I forgot about it. The other examples are complex highway intersections.

I was thinking of right hand exits where a concurrent highway of a mainline exits and continues on, sometimes involving an underpass of the mainline. Yeah you have to get off the mainline to stay on it, so it could be called a TOTSO. But a right hand exit (in countries with right-hand traffic) seems like very typical highway design. So I feel there's a better term to describe this: a highway split, or concurrency split!

[ran4sh]

I-5 and I-10 may not be officially defined as a concurrency, but functionally it is one, as otherwise I-10 would be discontinuous. There may be other CA examples that I'm forgetting right now.

[Ned Weasel]

Both of I-70's TOTSOs on the Pennsylvania Turnpike happen where it is concurrent with I-76, so yeah.

Also, I-80's TOTSO on the Indiana Toll Road happens where it is concurrent with I-90, and I-90's TOTSO on the Ohio Turnpike happens where it is concurrent with I-80.

[skluth]

Is I-215 in Riverside, CA a TOTSO? Sure feels like you're taking an exit, in either direction. One leg is multiplexed with CA-60.

Then there's I-210 in Pasadena.

And I-10 northeast of downtown LA, where one leg is shared with I-5.

Another concurrency TOTSO occurs between CA-2 and I-210 in La Canada Flintridge.

Back where I grew up, I-95 has two TOTSOs where it enters and leaves MA-128.

Also US-3 and MA-128/I-95 in Burlington.

I-215 in Riverside may change freeways but that interchange is also between CA 60 and CA 91. Both were originally US highways which predate the interstate system and are important corridors themselves. I-210 in Pasadena is a TOTSO from my understanding of the term. However both are 3DIs and I don't think it's unusual for 3DIs to move from one freeway to another. I believe the I-10 San Bernardino Freeway at I-5 is also a TOTSO.

[ilpt4u]

Both of I-70's TOTSOs on the Pennsylvania Turnpike happen where it is concurrent with I-76, so yeah.

Also, I-80's TOTSO on the Indiana Toll Road happens where it is concurrent with I-90, and I-90's TOTSO on the Ohio Turnpike happens where it is concurrent with I-80.

I-76 and I-80 both TOTSO the Ohio Turnpike near Youngstown

[TheHighwayMan3561]

MN 5 at both ends of the I-494 duplex
MN 55 at the west end of the MN 62 duplex

[TheStranger]

I-5 and I-10 may not be officially defined as a concurrency, but functionally it is one, as otherwise I-10 would be discontinuous. There may be other CA examples that I'm forgetting right now.

For that matter, 5 and 10 each have TOTSO moments through East Los Angeles.  The northern junction is the more obvious one (I-10 leaves the San Bernardino Freeway westbound to follow the Golden State Freeway in order to reach the Santa Monica Freeway, while the short segment of the San Bernardino (former US 60/70/99) leading to the San Bernardino Split interchange with US 101 is part of California's definition of "Route 10" but not I-10).

The main portion of the East Los Angeles Interchange has I-5 performing a TOTSO off the Santa Ana Freeway (which continues northwest as the route's original designation of US 101) to switch over to the Golden State Freeway.

---

Thought of a TOTSO situation that involves a concurrency and also was exacerbated by external situations:

In Daly City, there's a short concurrency of I-280 and Route 1 between John Daly Boulevard (near the SF city limit) and the Serramonte Shopping Center.

The section of 1 between Pacifica and the northern 280/1 junction exists in part due to a 1956 earthquake that damaged a coastline segment along Thornton Beach, which led to the modern freeway routing from Pacifica to Serramonte.  Today, 1 TOTSO's off 280 south.

Meanwhile, prior to 1968, I-280 was planned to continue north along the existing Route 1 freeway (mostly known as Junipero Serra Boulevard) from John Daly to Font Boulevard in San Francisco, then north parallel to 1 via Junipero Serra, 7th Avenue, and then (after cutting through Golden Gate park and interchanging with the planned Western Freeway part of I-80) rejoining today's 1 along Park Presidio.   Due to the freeway revolts, this was shelved past Font permanently.

The 1968 rerouting thus created a TOTSO - 280 now goes off from the Junipero Serra Freeway and onto the Southern Freeway before entering SF, while 1 continues north to head towards Font and then to 19th Avenue.  This has the interesting effect that drivers taking 1 from SF to Pacifica and drivers using 280 from Daly City to SF all have to merge to the other side of the road for their respective TOTSO at some point.

--

A TOTSO saga involving a multi-concurrency in Sacramento:

1968-1982: I-80 east and west had to turn off to stay on at the Oak Park Interchange with US 50, as did Route 99 northbound.

1983-2016: Business I-80 established as a concurrency with an extended US 50.  Along US 50 east in Oak Park, Business 80 turned off to go eastbound with Route 99 turning off to go southbound.

2017-present: Business 80 cut back to end at Route 99 and US 50.

The numbered route 99 (whether US 99E or state Route 99) originally did not have a TOTSO at this spot (as 99E continued along with I-80 all the way to Roseville in the mid-1960s) but with the changeover to state route, 99 has since had to switch in an L-shaped pathway between two other freeways (today's 50 and 5) since then.

50 actually went from having a TOTSO setup in the 1960s (following 99 to today's N Street exit off Business 80) but now continues directly west on the mainline carriageway to West Sacramento (which used to be all I-80).

[Dirt Roads]

Not quite the same, but how about two Interstates approaching each other on the same section of freeway and both of them TOTSO to create a concurrency?  The main north-south spine along the Elk River in Charleston, West Virginia carries I-64 from the west and I-77 from the north, and they both leave the highway to run along the north side of downtown towards the West Virginia Turnpike.  I'm pretty sure that I've seen this situation somewhere else, but I can't remember where.

[Hobart]

Both of I-70's TOTSOs on the Pennsylvania Turnpike happen where it is concurrent with I-76, so yeah.

Also, I-80's TOTSO on the Indiana Toll Road happens where it is concurrent with I-90, and I-90's TOTSO on the Ohio Turnpike happens where it is concurrent with I-80.

To add to the madness, I-80's TOTSO in Northwest Indiana is I-80 shifting from one concurrency (I-90) to another (I-94).

[SkyPesos]

Not quite the same, but how about two Interstates approaching each other on the same section of freeway and both of them TOTSO to create a concurrency?  The main north-south spine along the Elk River in Charleston, West Virginia carries I-64 from the west and I-77 from the north, and they both leave the highway to run along the north side of downtown towards the West Virginia Turnpike.  I'm pretty sure that I've seen this situation somewhere else, but I can't remember where.

A few more I can think of
- I-65/70 north interchange
- I-35/70 east interchange

Including the one above, I-70 have 3 TOTSOs in downtown KC, and it "bumps"  with an I-64 TOTSO in East St Louis. Could be the interstate with the most TOTSOs, but I counted a lot in I-80 and I-94 as well.

[skluth]

Not quite the same, but how about two Interstates approaching each other on the same section of freeway and both of them TOTSO to create a concurrency?  The main north-south spine along the Elk River in Charleston, West Virginia carries I-64 from the west and I-77 from the north, and they both leave the highway to run along the north side of downtown towards the West Virginia Turnpike.  I'm pretty sure that I've seen this situation somewhere else, but I can't remember where.

A few more I can think of
- I-65/70 north interchange
- I-35/70 east interchange

Including the one above, I-70 have 3 TOTSOs in downtown KC, and it "bumps"  with an I-64 TOTSO in East St Louis. Could be the interstate with the most TOTSOs, but I counted a lot in I-80 and I-94 as well.

The TOTSOs in KC are mostly irrelevant as most drivers use I-670 through downtown KC. I have no idea why I-70 takes its circuitous route through KC.

[NE2]

Of course they can. US 1-9 leaves the Pulaski Skyway with NJ 139 beginning ahead.

[wanderer2575]

Why limit this to freeways?  Isn't any surface route(s)' turning from one road onto another at an intersection also a TOTSO?

For example, the M-66/M-72 concurrency at US-131 south of Kalkaska:  https://goo.gl/maps/DP5ts7osX7ByexHj9

[Bickendan]

I-84/US 30/ORH 2 at NE 102nd Ave, with the unnumbered mainline (which would have been I-80N/84 if the Mt Hood Frwy were built) going west to a three-level T with I-205/ORH 64.

This one is interesting because had the Mt Hood been built, US 30 would have been the TOTSO to the Banfield Frwy, with its ORH xx beginning/ending there, while I-84/ORH 2 going west to 95th Age, and ORH 2 ending there instead of at I-5 (while I-84 would have had a concurrency with I-205/ORH 64, then its own TOTSO at US/ORH 26).

Speaking of US 26, at the eastern end of the Sunset, it exists the mainline to very brief overlap with I-405/ORH 61, while ORH 47 is the mainline ramp onto SW Market St. 47 now terminates at SW 13th instead of following the Market/Clay couplet to SW Naito and Harbor.

US 30 from NW Portland to I-84 might qualify (Fremont Stack; Rose Quarter).

[Ned Weasel]

The TOTSOs in KC are mostly irrelevant as most drivers use I-670 through downtown KC. I have no idea why I-70 takes its circuitous route through KC.

Because that alignment of I-70 was there first, and they never bothered to re-route it.

[skluth]

Why limit this to freeways?  Isn't any surface route(s)' turning from one road onto another at an intersection also a TOTSO?

For example, the M-66/M-72 concurrency at US-131 south of Kalkaska:  https://goo.gl/maps/DP5ts7osX7ByexHj9

Maybe because you can find one in almost every county. Sometimes a highway even does it twice within a short distance like WI 55 through Shawano.

[kirbykart]

Sure they can, both ends of the I-90/OH 2 concurrency in downtown Cleveland definitely count.

[pderocco]

Why limit this to freeways?  Isn't any surface route(s)' turning from one road onto another at an intersection also a TOTSO?

For example, the M-66/M-72 concurrency at US-131 south of Kalkaska:  https://goo.gl/maps/DP5ts7osX7ByexHj9

https://pbase.com/pderocco/image/108888145

This was actually part of US-395 once.

[PurdueBill]

In the vein the OP asked about (TOTSO with staying straight beginning a new route), US 62 is the "victim" of this twice in northeast Ohio, both involving diamond interchanges:

US 62 WB has to exit north of Salem while unsigned OH 14T takes over if you don't exit (OH 45 is also along for the ride with US 62 at this point and also TOTSO)   https://goo.gl/maps/c1ZrSYPX9U3LaEz47
US 62 EB has to exit while unsigned US 62T continues for several more miles around Alliance    https://goo.gl/maps/HEN25z6QnbYXLEE36

(The connection between the two has lingered in plans and possibilities for a while but this year they are demolishing the bridge at the end of 62T, probably eliminating the chances of 14T and 62T being connected north of Beloit to make one US 62 expressway.)

Also in the region, on I-76 EB coming in to Akron, "doing nothing" puts you on I-277 EB while 76 has to TOTSO.  (Just 2 miles north of there, 76 has to take ramps at another trumpet at I-77 but there is not a new route involved as per the OP's original question.  (76 hands its multiplex with US 224 to I-277 at the TOTSO.)

[Bickendan]

Two more in Oregon: ORH 2 at ORH 6 (ORH 2 leaves I-84/US 30 and transitions onto US 730)

ORH 26 at ORH 53 (ORH 26 leaves US 26 and transitions onto OR 35).