Why does Maryland sign non-Interstate freeways at 55 MPH max?

[NE2]

There's a very fine (non-existent?) line between a RIRO and an at-grade. Presumably he's talking about this one: http://maps.google.com/maps?hl=en&ll=39.016462,-76.485502&spn=0.003718,0.008256&gl=us&t=m&z=18&layer=c&cbll=39.016414,-76.486632&panoid=uER7aS3pCkUujfkAgHj3bg&cbp=12,43.23,,0,10.13

I would never consider that to be an at-grade intersection.

It's an intersection between a local road (actually a segment of MD 648) and westbound US 50, and it's at-grade. Therefore it's an at-grade intersection.

[deathtopumpkins]

Vermont, NH, and Maine do the same thing: 50 on most roads that would be at least 55 anywhere else.

False. I think you meant to say Connecticut, RI, and Mass.
Vermont and New Hampshire both post 2-lane high-quality roads at 55 (generally mostly expressways), but don't have very many roads that could handle speeds that high to begin with. If you want to drive 55 in NH, drive NH 9 or NH 125, both have numerous 55 mph stretches. Maine posts almost every rural state highway at 55. I travel to Maine every weekend and have noticed very few 50 mph zones - the vast majority being 55, which is a welcome change from southern New England.

On the other hand, I cannot think of a single 2-lane road off the top of my head in either CT or RI that's posted above 50, not even in the far corners of the state, and I can name some in Massachusetts, but only two that aren't super-2 freeways (US 1 from Rowley to Newburyport and a brief stretch near Attleboro)



Regarding RIROs v. at-grades, I consider it to be a RIRO if there is some semblance of a median separating entering and exiting traffic (even just a painted taper), if it has some semblance of acceleration/deceleration lanes, and if it is treated as an exit rather than an intersection (i.e. exit sign instead of street blade).

[Beltway]

He's correct about the exits on Kent Island, though. Some of those are not at all suitable for high-speed traffic. The Merritt Parkway interchanges with the stop signs are better than some of the Kent Island exits.

Actually given the -extremely- long accell and decel lanes on US-50, there is no reason why it couldn't be 65 mph on the mainline.

I didn't say it couldn't be. I said they're unsuitable for high-speed traffic.

So what are you saying, that the ramps should be able to handle 65 mph traffic?

What I am saying is that the accell and decel lanes are plenty long enough to transition gradually to and from 65 mph on the mainline, and pass through the 25 mph curves of the ramp.

[Beltway]

There's a very fine (non-existent?) line between a RIRO and an at-grade. Presumably he's talking about this one: http://maps.google.com/maps?hl=en&ll=39.016462,-76.485502&spn=0.003718,0.008256&gl=us&t=m&z=18&layer=c&cbll=39.016414,-76.486632&panoid=uER7aS3pCkUujfkAgHj3bg&cbp=12,43.23,,0,10.13

I would never consider that to be an at-grade intersection.

It's an intersection between a local road (actually a segment of MD 648) and westbound US 50, and it's at-grade. Therefore it's an at-grade intersection.

It is not an intersection, because the local traffic does not cross active mainline lanes.

[vdeane]

Vermont, NH, and Maine do the same thing: 50 on most roads that would be at least 55 anywhere else.

False. I think you meant to say Connecticut, RI, and Mass.
Vermont and New Hampshire both post 2-lane high-quality roads at 55 (generally mostly expressways), but don't have very many roads that could handle speeds that high to begin with. If you want to drive 55 in NH, drive NH 9 or NH 125, both have numerous 55 mph stretches. Maine posts almost every rural state highway at 55. I travel to Maine every weekend and have noticed very few 50 mph zones - the vast majority being 55, which is a welcome change from southern New England.

On the other hand, I cannot think of a single 2-lane road off the top of my head in either CT or RI that's posted above 50, not even in the far corners of the state, and I can name some in Massachusetts, but only two that aren't super-2 freeways (US 1 from Rowley to Newburyport and a brief stretch near Attleboro)



Regarding RIROs v. at-grades, I consider it to be a RIRO if there is some semblance of a median separating entering and exiting traffic (even just a painted taper), if it has some semblance of acceleration/deceleration lanes, and if it is treated as an exit rather than an intersection (i.e. exit sign instead of street blade).

The rural roads in VT and NH that are posted 50 would be posted 55 in NY (indeed, 50 is almost never posted in NY).

I believe a good chunk of US 2 in Maine west of I-95 is posted 50 as well.

[deathtopumpkins]

Vermont, NH, and Maine do the same thing: 50 on most roads that would be at least 55 anywhere else.

False. I think you meant to say Connecticut, RI, and Mass.
Vermont and New Hampshire both post 2-lane high-quality roads at 55 (generally mostly expressways), but don't have very many roads that could handle speeds that high to begin with. If you want to drive 55 in NH, drive NH 9 or NH 125, both have numerous 55 mph stretches. Maine posts almost every rural state highway at 55. I travel to Maine every weekend and have noticed very few 50 mph zones - the vast majority being 55, which is a welcome change from southern New England.

On the other hand, I cannot think of a single 2-lane road off the top of my head in either CT or RI that's posted above 50, not even in the far corners of the state, and I can name some in Massachusetts, but only two that aren't super-2 freeways (US 1 from Rowley to Newburyport and a brief stretch near Attleboro)



Regarding RIROs v. at-grades, I consider it to be a RIRO if there is some semblance of a median separating entering and exiting traffic (even just a painted taper), if it has some semblance of acceleration/deceleration lanes, and if it is treated as an exit rather than an intersection (i.e. exit sign instead of street blade).

The rural roads in VT and NH that are posted 50 would be posted 55 in NY (indeed, 50 is almost never posted in NY).

I believe a good chunk of US 2 in Maine west of I-95 is posted 50 as well.

That may well be, but I can only vouch for southern and coastal Maine. Off the top of my head, US 1, US 202, ME 9, ME 236, ME 4, and ME 11 are all posted at least partially at 55. And that's just from my trip up there last weekend, which didn't even go farther up than Kennebunk. The only state highways that were not at least partially posted up to 55 were ME 91 (narrow and twisty), ME 103 (old alignment of ME 236 and narrow, twisty road though Kittery), ME 9A (mostly settled area), and US 1A (mostly settled area).

I still insist that you mix up northern and southern New England when it comes to speed limits.
Like I said in my previous post, nowhere do CT or RI post 2-lane undivided roads above 50, Mass. does it occasionally, VT does it sometimes, NH does it fairly often, and Maine does it more often than not.

[NE2]

It is not an intersection, because the local traffic does not cross active mainline lanes.

It's not a four-way intersection. But it's certainly a T intersection.

[Beltway]

It is not an intersection, because the local traffic does not cross active mainline lanes.

It's not a four-way intersection. But it's certainly a T intersection.

It is -not- an intersection. 

A "T intersection" allows left turns to and from the main road.  US-50 does not.

[NE2]

It is not an intersection, because the local traffic does not cross active mainline lanes.

It's not a four-way intersection. But it's certainly a T intersection.

It is -not- an intersection. 

A "T intersection" allows left turns to and from the main road.  US-50 does not.

Nope. An intersection is a place where two roads intersect - here the MD 648 segment and westbound US 50. http://itd.idaho.gov/projects/d3/ID55Corridor/Caldwell_2009/spacingUrbanSuburban.pdf "RIRO = Intersection that limits vehicle access
to right-in/right-out movements"

[cpzilliacus]

It is not an intersection, because the local traffic does not cross active mainline lanes.

It's not a four-way intersection. But it's certainly a T intersection.

It is -not- an intersection. 

A "T intersection" allows left turns to and from the main road.  US-50 does not.

I am not going to argue the semantics of this.  But the point where Md. 648 meets the westbound side of U.S. 50/U.S. 301 is left over from the days when the U.S. 50/U.S. 301 was an arterial highway, not the (mostly) limited-access road that exists today.   Md. 648 used to be connected to U.S. 50/U.S. 301 on the south side as well, but access there has been blocked-off for quite a few years.

I believe that access to Md. 648 remains only because the other access point to this segment of Md. 648 is from an intersection with Md. 2 (Ritchie Highway), north of the Md. 2/U.S. 50/U.S. 301/Md. 450 interchange (Google Maps here (Md. 648 is Baltimore-Annapolis Boulevard)).  That intersection has difficult geometrics (especially for trucks trying to reach the lumberyard located on Md. 648 between Md. 2 and U.S. 50/U.S. 301).

[Beltway]

Long accell and decell lanes could be built within existing right-of-way, that would make that exit similar to the situation on Kent Island. 

Even currently I would not consider that segment of US-50/US-301 to be not a freeway.

[1995hoo]

To return to the original topic:

If it weren't for the statute imposing a maximum 55-mph limit, one road in Maryland that could easily accommodate a 60- or 65-mph speed limit is most of US-15 from north of Frederick to the Pennsylvania line. Not necessarily the portion through Frederick, which has a lot of traffic, but the portion north of there is generally wide-open and traffic entering from the at-grade intersections can see the road well enough that there wouldn't be many problems with someone cresting a hill at high speed to find someone turning out into the road. I seem to recall the road having a slightly twistier and narrower feel to it around Thurmont, so perhaps maintaining the 55-mph limit through there might be appropriate as well.

I usually set my cruise control at around 65 mph on that part of US-15 and I've never had any problems. I'm a lot more wary on the 65-mph portion in Pennsylvania if I'm coming back late at night (and I've come back from Hershey Bears games quite late on occasion) because that road seems like it ought to have a higher likelihood of deer crossing the road.

[vdeane]

I still insist that you mix up northern and southern New England when it comes to speed limits.
Like I said in my previous post, nowhere do CT or RI post 2-lane undivided roads above 50, Mass. does it occasionally, VT does it sometimes, NH does it fairly often, and Maine does it more often than not.

Most of my New England driving has been in Vermont; very little in southern New England.  Almost all roads VT posts at 50 (which is almost everything in rural areas that isn't an interstate) would be 55 in NY.  Plus VT drivers typically go 45 on these roads.  Not fun.

It is not an intersection, because the local traffic does not cross active mainline lanes.

It's not a four-way intersection. But it's certainly a T intersection.

It is -not- an intersection. 

A "T intersection" allows left turns to and from the main road.  US-50 does not.

One way streets are now freeways in between traffic lights?

[Beltway]

<<< One way streets are now freeways in between traffic lights? >>>

Oh please.  We are not talking about a street, we are talking about the US-50 freeway, which is over 50 miles long, and you are questioning the design of -one- exit.

[cpzilliacus]

To return to the original topic:

If it weren't for the statute imposing a maximum 55-mph limit, one road in Maryland that could easily accommodate a 60- or 65-mph speed limit is most of US-15 from north of Frederick to the Pennsylvania line. Not necessarily the portion through Frederick, which has a lot of traffic, but the portion north of there is generally wide-open and traffic entering from the at-grade intersections can see the road well enough that there wouldn't be many problems with someone cresting a hill at high speed to find someone turning out into the road. I seem to recall the road having a slightly twistier and narrower feel to it around Thurmont, so perhaps maintaining the 55-mph limit through there might be appropriate as well.

Hoo, I strongly agree.  U.S. 15 from Md. 26 north to the Pennsylvania border could be posted 65 MPH - even passing Thurmont.

I usually set my cruise control at around 65 mph on that part of US-15 and I've never had any problems. I'm a lot more wary on the 65-mph portion in Pennsylvania if I'm coming back late at night (and I've come back from Hershey Bears games quite late on occasion) because that road seems like it ought to have a higher likelihood of deer crossing the road.

Another Maryland rural arterial that could have a 65 limit is U.S. 301 from Queenstown to the Delaware border.  The land is very nearly flat, and the sight distances are long.

[cpzilliacus]

My list of suggested speed limit increases in Maryland (not supported by any engineering study):

Arterials and expressways:

U.S. 301 from (but not including) the Nice Bridge to Bowie - 60 MPH
U.S. 301 from Queenstown to the Delaware border - 65 MPH
U.S. 50/U.S. 301 from Md. 450 (West Street) to Queenstown (not including the WPL Bridge) - 60 MPH
U.S. 50 from Queenstown to the Salisbury Bypass - 60 MPH (except passing built-up areas of Easton and Cambridge)
U.S. 15 from Md. 26 to the Pennsylvania line - 65 MPH
U.S. 29 from Md. 650 (New Hampshire Avenue) to I-70 - 60 MPH
Md. 4 (Pennsylvania Avenue) from I-95 to Md. 258 (Bay Front Road) - 60 MPH (maybe higher if the signals at Westphalia Road, Suitland Parkway and Dower House Road ever get replaced by grade-separated interchanges)
Md. 5 (Branch Avenue) from I-95 to south of Md. 223 (Woodyard Road) - 60 MPH

Interstates and freeways:

Md. 200 - 65 MPH (great candidate for N.J. Turnpike-style variable speed limits)
Md. 100 between U.S. 29 and I-97 - 65 MPH
Md. 10 between I-695 and Md. 100 - 65 MPH
Md. 32 between Md. 108 and I-97 (except between B-W Parkway and Md. 198) - 65 MPH
I-95 "Between the Beltways" - 70 MPH
I-795 - 70 MPH
I-95 (JFK Highway) - 75 MPH
I-70 between Md. 144 east of Frederick and U.S. 29 - 75 MPH
I-270 - 65 MPH
I-70 between Md. 144 east of Hancock and Md. 66 (Mapleville Road) - 75 MPH
I-68 between the West Virginia border and Md. 546 (Finzel Road) - 75 MPH
U.S. 50 between Md. 410 (East West Highway) and Md. 450 (West Street) - 75 MPH
I-695 (except at the approaches to and crossing the F. S. Key Bridge) - 65 MPH
I-95/I-495 from the Wilson Bridge to the I-95 interchange in College Park - 65 MPH
I-97 - 70 MPH

[1995hoo]

I might add MD-210 to that list–at least the part between MD-228 in Accokeek and the Beltway. (I am not familiar enough with the part beyond MD-228 to comment. I've only been down to the end of the road one time, as there is very little reason to go that way unless you live there or have business at the Navy base.) As it is the speed limits on that road are pretty much universally ignored. It would probably be a fine candidate for variable speed limits if drivers could be convinced to take such limits seriously, as I recognize that the road does become very congested at certain times of day and that at those times it is desirable to try to keep the traffic going slower. But I can think of any number of weekday afternoons when I've been on that road and I've been one of the slowest people on the road at 65 mph.

I wouldn't argue with the idea of NOT raising the speed limit on US-301 through Waldorf, though. That area feels busy and visually cluttered to me every time I pass through.

Regarding I-270, you mentioned earlier in this thread how the 55-mph speed limit is universally ignored. You're not kidding there. If I try to set the cruise control between 65 and 70 I find I'm still one of the slowest people on the road. For a revised speed limit, though, I kind of like the idea of a split speed limit for the local and express lanes whereby the express lanes would have a higher limit than the local lanes would. The local carriageways are two lanes and have a lot of traffic merging from both directions (people entering I-270 on the right; people moving from express to local lanes on the left). I find it hard to quibble with the idea of a lower speed limit for those lanes under that particular set of circumstances.

[cpzilliacus]

I might add MD-210 to that list–at least the part between MD-228 in Accokeek and the Beltway. (I am not familiar enough with the part beyond MD-228 to comment. I've only been down to the end of the road one time, as there is very little reason to go that way unless you live there or have business at the Navy base.) As it is the speed limits on that road are pretty much universally ignored. It would probably be a fine candidate for variable speed limits if drivers could be convinced to take such limits seriously, as I recognize that the road does become very congested at certain times of day and that at those times it is desirable to try to keep the traffic going slower. But I can think of any number of weekday afternoons when I've been on that road and I've been one of the slowest people on the road at 65 mph.

Md. 210 (Indian Head Highway) is functionally classified as an expressway from the I-95/I-495 interchange on the south edge of Forest Heights south to the Prince George's County/Charles County border, on the way to Indian Head (it is defined as an arterial in Charles County, presumably because it has driveways connecting directly to the highway, and as one approaches the Town of Indian Head (yes, it is a municipality), it resembles a wide urban street). 

But except for the interchange in Forest Heights, all of its intersections are at-grade, and I frequently hear of "serious" and sometimes fatal wrecks.

A colleague has told me that many of those fatal wrecks involve "sport" motorcycles (a/k/a "crotch rockets"), but there are also plenty of "T-bone" crashes involving vehicles with four or more wheels.

So I am not so enthused about raising the speed limit on 210 above the current 55 MPH - unless and until the state finds a large pot of money to replace the  signalized intersections with grade-separated interchanges (and that will be expensive because there are so many intersections).

I wouldn't argue with the idea of NOT raising the speed limit on US-301 through Waldorf, though. That area feels busy and visually cluttered to me every time I pass through.

And the numerous signalized intersections in Waldorf almost assure that  nobody is going to get through  there quickly anyway. So leave that segment at 55 MPH.

Regarding I-270, you mentioned earlier in this thread how the 55-mph speed limit is universally ignored. You're not kidding there. If I try to set the cruise control between 65 and 70 I find I'm still one of the slowest people on the road. For a revised speed limit, though, I kind of like the idea of a split speed limit for the local and express lanes whereby the express lanes would have a higher limit than the local lanes would. The local carriageways are two lanes and have a lot of traffic merging from both directions (people entering I-270 on the right; people moving from express to local lanes on the left). I find it hard to quibble with the idea of a lower speed limit for those lanes under that particular set of circumstances.

That's a good idea.  55 in the "local" lanes, 65 or maybe 70 in the "through" or "main" or "express" lanes.

[mcmc]

I-795 - 70 MPH
I-95 (JFK Highway) - 75 MPH
I-70 between Md. 144 east of Frederick and U.S. 29 - 75 MPH

70 MPH! 75 MPH! Sounds great! But is there a single person associated with the government of Maryland that supports raising the maximum statewide limit above 65 MPH?

[bugo]

Sounds like Maryland's government are a bunch of pussies.  Oklahoma's government is beyond fucked up, but at least they let us drive 75 on the turnpikes.

[cpzilliacus]

I-795 - 70 MPH
I-95 (JFK Highway) - 75 MPH
I-70 between Md. 144 east of Frederick and U.S. 29 - 75 MPH

70 MPH! 75 MPH! Sounds great! But is there a single person associated with the government of Maryland that supports raising the maximum statewide limit above 65 MPH?

Plenty of drivers with  Maryland license plates seem to like it fine, though I don't know if they vote.

[vdeane]

<<< One way streets are now freeways in between traffic lights? >>>

Oh please.  We are not talking about a street, we are talking about the US-50 freeway, which is over 50 miles long, and you are questioning the design of -one- exit.

Freeways sometimes have at-grade intersections.  Just look at NY 17.  Or NY 198 (which has a traffic light!).  US 15 had at-grades north of Williamsport just like this that were recently removed.  Also, take a look at exit 111 on NY 17.  At first glance it looks just like this, but unlike this, it uses guide signs instead of a street blade (!), and is striped as an interchanged; this is striped as an intersection with a right turn lane (otherwise, there would be an "island" painted with white lines).

[NE2]

Freeways sometimes have at-grade intersections.  Just look at NY 17.  Or NY 198 (which has a traffic light!).

These aren't freeways. RIRO intersections are often tolerated on freeways, but cross traffic is completely prohibited.

[vdeane]

NY 198 is a freeway both west and east so I'm not sure how you'd want to classify it, but in any case, both are considered freeways by upstate NY locals (especially since NY 17 now has no traffic lights west of Harriman).

Of course, I'm sure Florida, with it's newer roads, doesn't have to deal with any of these issues.

[deathtopumpkins]

The definition of a freeway does not vary place-to-place. Whether the locals consider something a freeway does not make it a freeway. If it has intersections with cross traffic, it is an expressway or an arterial, not a freeway.