What is a Super-2, really?

[vdeane]

IMO those who design highways don't need a term for what they call super-2.  Everything else is substandard and IMO needs to be upgraded.  Just tell it like it is: those are modern two-lane roads and everything else is deficient and obsolete.

That definition of super-4 sounds functionally identical to an expressway to me.

Now, as roadgeeks, we actually differentiate types of freeways that the DOT definitions have no terms for.  That would seem to me to be the better system.  I imagine the DOT definition of super-2 evolved out of political motivations of not wanting to admit that so many roads don't meet the standards.

[hotdogPi]

IMO those who design highways don't need a term for what they call super-2.  Everything else is substandard and IMO needs to be upgraded.  Just tell it like it is: those are modern two-lane roads and everything else is deficient and obsolete.

Every road that isn't limited access is deficient and obsolete?

[vdeane]

That would be a two-lane expressway, but I would consider a road without full shoulders and a high-speed geometry to be obsolete.  The definition J N Winkler gave did not imply full access control, or at least my reading of it didn't (I was picturing this).  In any case, it would seem that a roadgeek super-2 would be a subset of the DOT super-2, and I would say the roadgeek differentiation is the more important one.

I'm not aware of many undivided two lane roads with at-grades and full access control.  The only ones I can think of are the Round Lake Bypass, part of NY 104 (maybe), and Autoroutes 30, 55, and 955.

[jakeroot]

What's the difference between a standard two lane highway with passing lanes, and a Super-2?

None really, except that Super Two implies full shoulders with geometry, roadside development, and access control to generally higher standards.

So basically every modern two lane highway is a Super-2?

If "modern" implies provision of passing lanes, full shoulders, limitation of access, and high-standard geometry--yes.

So what's the point of the term anymore? I can imagine a time when a Super-2 highway was important. Old standards often resulted in roads that were narrow, lacked shoulders, and had curves that were far too sharp. But modern standards basically dictate that any new two lane highway be of Super-2 quality.

By the way, what exactly is limited access? I keep seeing this term thrown around, but I can't quite seem to nail down exactly what it means. I would have thought "limited access" meant RIROs, over or underpasses, etc. Is it meant to imply that most junctions are RIRO except for very important ones?

[J N Winkler]

IMO those who design highways don't need a term for what they call super-2.  Everything else is substandard and IMO needs to be upgraded.  Just tell it like it is: those are modern two-lane roads and everything else is deficient and obsolete.

So what's the point of the term anymore? I can imagine a time when a Super-2 highway was important. Old standards often resulted in roads that were narrow, lacked shoulders, and had curves that were far too sharp. But modern standards basically dictate that any new two lane highway be of Super-2 quality.

I don't think a state DOT would agree that the Super Two term is unnecessary.  It might be if we were still building two-lane roads de novo, but by and large we aren't--the vast majority of two-lane rural primary state highway construction that occurs now is modernization of routes that already exist.  Labelling such an improvement as a Super Two tells the public that the scope of the improvement is not expansion to four-lane divided, or to some other cross section that has succeeded the 1930's three-lane road as an intermediate stage between unmodernized two-lane and divided highway.  (Others that have been tried include the poor-boy and various flavors of S2+1 such as the "alternating four-lane" segments of SR 5 in Missouri.)

The paved-shoulders element of the Super Two definition is also important because the current (2011) edition of the Green Book still allows partially surfaced shoulders and the surfacing is not necessarily pavement.  Shoulders are also still allowed to be as narrow as 2 ft (on low-volume roads).

The distinction between ordinary two-lane and Super Two in the US is comparable to that between S2 (single carriageway, two lanes) and WS2 (wide single carriageway) in Britain.

By the way, what exactly is limited access? I keep seeing this term thrown around, but I can't quite seem to nail down exactly what it means. I would have thought "limited access" meant RIROs, over or underpasses, etc. Is it meant to imply that most junctions are RIRO except for very important ones?

Limited access is an elastic term that implies some degree of access control that is inferior to full control; the phrase by itself does not guarantee that any particular type of access point will be used.  The degree of control in effect should be separately evident from the context.

[jakeroot]

I don't think a state DOT would agree that the Super Two term is unnecessary.

Which states use this term, exactly? NE2 posted links to TxDOT, M(I)DOT, and NDOR websites. Buts that's three of 50. I believe the FHWA recognizes the term, but they don't publicise road works. WSDOT doesn't seem to have this term posted on their website, and I don't think Oregon nor Idaho use the term either.

If WSDOT pursues work that involves shoulder widening or passing lane additions, they generally advertise the project as a "shoulder widening" or "add passing lanes" project (sometimes grouped together as "road safety improvements").

[froggie]

Though there isn't any documentation online, MnDOT has used the "Super-2" term in reference to upgrades to US 12 between Willmar and Wayzata that began in the early 1990s.  The associated definition was generally along the lines of what J N Winkler described upthread....with wide shoulders, passing and turn lanes, and better geometry, but not necessarily limited-access.

[J N Winkler]

KDOT uses the term Super Two (albeit in scare quotes) in reference to US 400 between Leon and Parsons in this 2008 piece:

http://www.ksdot.org/Assets/wwwksdotorg/PDF_Files/Transportation%20Infrastructure%20Investment%20and%20the%20Kansas%20Economy%20Final%2011-12-08.pdf

SDDOT also uses the term:

http://www.sddot.com/transportation/highways/planning/specialstudies/docs/epdExecutiveSummaryReport.pdf

So does NDDOT (in reference to an upgrade option for US 2):

http://www.dot.nd.gov/projects/us2pdfs/SECTION%207%20(part%202).pdf

[hbelkins]

I have never heard of the term "Super-2" being used in official documentation, or that it's a specific engineering term.

To me, "Super-2" is an abbreviation of sorts for "2-Lane Superhighway." So that begs the question, "What is a superhighway?'

To me, a superhighway is a freeway. The term freeway denotes full access control and grade separations. So I would define "Super-2" as a two-lane freeway.

[MisterSG1]

What I would personally consider a bonafide Super 2 is NL-2 west of the Manuels exit. I assume probably none of you here except for maybe Alps have driven on that road.

For the record, NL-2 is a freeway heading west until you reach the Manuels Access Road, afterwards, NL-2 is:

-Completely Grade Separated, there are ZERO at grade crossings, all crossings are either overpasses or underpasses

-There are no driveways, and all accesses to this road occur only at ramps, thus it's 100% controlled access

ALSO, there are ZERO passing lanes on this road for the record


NL-75, a similar bypass road of NL-70 is at points a Super 2, and a regular 2 lane highway at other points, as it has intersections at the Harbour Grace access road for instead.

[J N Winkler]

I have never heard of the term "Super-2" being used in official documentation, or that it's a specific engineering term.

KyTC uses it.  Google turns up a hit in the 2008 standard specifications.

http://transportation.ky.gov/Highway-Design/Standard%20Drawing%20%20Sepia%20PDFs/SEPIA-SERIES-2008.pdf

That is as engineering-related as it gets.

To me, a superhighway is a freeway. The term freeway denotes full access control and grade separations. So I would define "Super-2" as a two-lane freeway.

That is not how KDOT or any other state DOT I know of defines it.  In pertinent part, the KDOT link I gave above reads:  "A $27 million bypass built in 2004 on a new alignment that re-routes US 400 around Parsons' downtown through formerly agricultural land north of Parsons and completes a fully-upgraded 'Super Two' route between Parsons and Wichita to the west and Missouri to the east."  Now, the Parsons bypass does have one grade-separated interchange at US 59, but the US 400 corridor as a whole is not two-lane freeway and has multiple intersections on the level.

I have done some further casual searching for state DOT documentation that uses the term Super Two.  So far, in addition to KS, SD, ND, and now KY, I have tried MT, WY, CO, WA, MN, and AZ and have struck out only in WY, WA, and AZ.  For all three of these states, I have found FHWA documentation that refers to particular improvements in these states as Super Two facilities.

Bottom line:  existing actual usage of the term Super Two is not restricted to two-lane freeways; and there is no shortage of official documentation (produced by state DOT personnel or contractors and hosted on servers owned or controlled by state DOTs) that uses it.

[plain]

I'm not sure what the true definition is because it's always been a foggy subject.. but I always believed it was a limited access 2 lane road with no driveways and grade separation at most of it's crossings with very few (if any) at-grade intersections at others. Whether or not at-grades is even supposed to exist on the road at all has always been up in the air...

The WV Turnpike was universally considered a Super-2 but had at-grade intersections at all 3 service plazas.

hbelkins mentioned the Mountain Pkwy in Kentucky. While that one at-grade technically disqualifies it from being a "full freeway" for it's entire length, it's still something most would consider a Super-2.

The Hal Rogers (forever Daniel Boone to me) Pkwy, also in Kentucky, has a number of at-grades even more so now than years past, but again because of its overall limited access nature it is also considered a Super-2 by most.

Oklahoma's Chickasaw Tpk has at-grades near its northeastern end but for the most part still a Super-2.

By the strictest of standards I think everyone can definitely agree US 6 in eastern Massachusetts is an excellent example of one.

[wxfree]

I vote for a Super-2 being a two-lane freeway.  I don't like the term "two-lane freeway" because a freeway is, in part, a multi-lane divided highway, so I'd rather have a different label for it and this one works because it suggests a two-lane superhighway.  As for what it actually is, I'm afraid that depends on whom you ask.  If we're voting, I vote for a two-lane highway with repeated passing lanes being called a "two-plus" road.

To get really technical, which I like to do, we'd also need a name for a two-lane not-quite-freeway with partial access control.  Maybe we should also distinguish between divided and undivided two-lane freeways.  I don't know how common divided ones are, but the two-lane southern part of the Chisholm Trail Parkway has a barrier both for safety and because without it some of the ramp tolls could be avoided by use of U-turns.  That road is divided, has full access control, and has passing lanes, so it's a Super-2 by every definition.

[Max Rockatansky]

The actual definition seems to be outdated by most modern road design or vague at best.  In modern terms I always thought of it as a divided two-lane road with limited access.  A good example of what I have in mind is the 18 mile stretch of US 1 between Florida City and Key Largo.

[jeffandnicole]

The actual definition seems to be outdated by most modern road design or vague at best.  In modern terms I always thought of it as a divided two-lane road with limited access.  A good example of what I have in mind is the 18 mile stretch of US 1 between Florida City and Key Largo.

I agree with this except for the divided portion.  I'd simply go with 2 lanes, full on/off access via interchanges, and no other access permitted.

To get really technical, which I like to do, we'd also need a name for a two-lane not-quite-freeway with partial access control. 

Well, one of the local nicknames given to US 322 between I-95 and US 1 in PA is the Killer Conchester Pike, but I don't think that's a term you're going for.

[Max Rockatansky]

The actual definition seems to be outdated by most modern road design or vague at best.  In modern terms I always thought of it as a divided two-lane road with limited access.  A good example of what I have in mind is the 18 mile stretch of US 1 between Florida City and Key Largo.

I agree with this except for the divided portion.  I'd simply go with 2 lanes, full on/off access via interchanges, and no other access permitted.

Actually I'm inclined to agree with that sentiment especially with examples like FL 570 and FL 407 where the access is strictly limited. 

[mapman1071]

Would Bethpage State Parkway on Long Island be a Super 2?

[plain]

Would Bethpage State Parkway on Long Island be a Super 2?

Absolutely. It's pretty tough to argue against that one.

[epzik8]

The following three pictures are from a segment of the Bel Air Bypass, which carries U.S. Route 1 around Bel Air, Maryland to the north of Baltimore. This segment is two lanes and has a freeway-style interchange at which Maryland Route 24 joins, leaving Maryland Route 924 to continue into downtown Bel Air; at that point the Bypass expands into four lanes. Looking at the pictures below, does anyone think it's an example of a Super-2?

[cpzilliacus]

Super-2 highways are somewhat common in the Nordic nations, and I have driven  them more there than I have here in the U.S. (though  the far northern section of I-95, from Bangor to Houlton, was originally built as a Super-2, but it widened out to four lanes divided at most of the interchanges, then back to two lanes undivided, probably the longest Super-2 I have ever experienced), and people we knew in Maine said that there were a lot of head-on fatal crashes on that part of the road (it was converted to a conventional four lane freeway many years ago).

Maryland had Super-2 sections of MD-695 (Baltimore Beltway, sometimes signed as I-695) approaching the F.S. Key Bridge toll crossing (the bridge itself always four lanes divided) on both sides.  The west side from MD-10 was converted to a four lane freeway first, then the east side from MD-151 was rebuilt as four divided lanes in the 1990's.

Sweden has attempted to reduce the crash problem on its Super-2 highways by putting a steel barrier in the middle to prevent drivers from forgetting that they are on a Super-2, also preventing passing for the most part, but providing (in some places) two lanes in one direction so that slower traffic can be  passed.  Sometimes that extra lane is intended to be a truck climbing lane, but not always. These three lane roads are sometimes called "2+1" - here is an  example of a 2+1 road with barrier between opposite directions of traffic.

Legally, such roads are defined as two lane (or sometimes three lane as described above) highways with full access control and where motorway traffic rules and laws apply (unnecessary stopping, pedestrians, bikes and horse-drawn vehicles are prohibited).

[machias]

That would be a two-lane expressway, but I would consider a road without full shoulders and a high-speed geometry to be obsolete.  The definition J N Winkler gave did not imply full access control, or at least my reading of it didn't (I was picturing this).  In any case, it would seem that a roadgeek super-2 would be a subset of the DOT super-2, and I would say the roadgeek differentiation is the more important one.

I'm not aware of many undivided two lane roads with at-grades and full access control.  The only ones I can think of are the Round Lake Bypass, part of NY 104 (maybe), and Autoroutes 30, 55, and 955.

NY 104 between Williamson (or so) and the Wayne-Cayuga County line comes to my mind as a Super 2. As does NY 3 between Hannibal and Fulton, NY 30A between the southern and northern city lines of Gloversville. 

Are these not super 2s?

[froggie]

By definitions that include limited-access but not full access control, yes those would generally qualify.  NY 104 would go from from NY 88 (not quite to Williamson) to the Wayne-Cayuga line.  NY 3 more or less fits.  If not for a couple of farm access points near the northern Gloversville line and a couple driveways near CR 154, NY 30A's super-2 section would extend to NY 30 and then another mile up NY 30 towards Mayfield.

[cpzilliacus]

By definitions that include limited-access but not full access control, yes those would generally qualify.  NY 104 would go from from NY 88 (not quite to Williamson) to the Wayne-Cayuga line.  NY 3 more or less fits.  If not for a couple of farm access points near the northern Gloversville line and a couple driveways near CR 154, NY 30A's super-2 section would extend to NY 30 and then another mile up NY 30 towards Mayfield.

Maryland has a few "almost" Super-2 highways, such as these:

Allegany County - U.S. 220 north of I-68 has some segments that are obviously intended to have full access control, but the interchange at I-68 is not a freeway-to-freeway design, and approaching the Pennsylvania border, there are at least two intersections at-grade.

Carroll County - MD-97 in Eldersburg has a section that resembles a Super-2, but has several at-grade intersections.

Frederick County - U.S. 15 from the roundabout at MD-464 to U.S. 340 (but has intersections at-grade).

Howard County - MD-32 from MD-108 at Clarksville in the south to north of Pfefferkorn Road in West Friendship nearly qualifies, but has an at-grade crossing at the SHA and Howard County road maintenance shops.

Worcester County - MD-90 from U.S. 50 to MD-528 in Ocean City even has a steel barrier to prevent passing for much of its length, but has at least one signalized at-grade intersection (I think there were once more).

[Joe The Dragon]

By definitions that include limited-access but not full access control, yes those would generally qualify.  NY 104 would go from from NY 88 (not quite to Williamson) to the Wayne-Cayuga line.  NY 3 more or less fits.  If not for a couple of farm access points near the northern Gloversville line and a couple driveways near CR 154, NY 30A's super-2 section would extend to NY 30 and then another mile up NY 30 towards Mayfield.

Maryland has a few "almost" Super-2 highways, such as these:


Howard County - MD-32 from MD-108 at Clarksville in the south to north of Pfefferkorn Road in West Friendship nearly qualifies, but has an at-grade crossing at the SHA and Howard County road maintenance shops.

That may not count as breakage in the highway as it's maintenance only area.

[froggie]

By definitions that include limited-access but not full access control, yes those would generally qualify.  NY 104 would go from from NY 88 (not quite to Williamson) to the Wayne-Cayuga line.  NY 3 more or less fits.  If not for a couple of farm access points near the northern Gloversville line and a couple driveways near CR 154, NY 30A's super-2 section would extend to NY 30 and then another mile up NY 30 towards Mayfield.

Maryland has a few "almost" Super-2 highways, such as these:

Allegany County - U.S. 220 north of I-68 has some segments that are obviously intended to have full access control, but the interchange at I-68 is not a freeway-to-freeway design, and approaching the Pennsylvania border, there are at least two intersections at-grade.

Carroll County - MD-97 in Eldersburg has a section that resembles a Super-2, but has several at-grade intersections.

Frederick County - U.S. 15 from the roundabout at MD-464 to U.S. 340 (but has intersections at-grade).

Howard County - MD-32 from MD-108 at Clarksville in the south to north of Pfefferkorn Road in West Friendship nearly qualifies, but has an at-grade crossing at the SHA and Howard County road maintenance shops.

Worcester County - MD-90 from U.S. 50 to MD-528 in Ocean City even has a steel barrier to prevent passing for much of its length, but has at least one signalized at-grade intersection (I think there were once more).

"Limited access", by definition in most states (although Virginia for some reason swaps the definitions of limited-access and controlled-access), allows at-grade intersections.  Based on personal experience, most of your mentions would meet the Super-2 definition I described upthread.