Whenever I go to Arizona and I'm in a dual left turn bay, I often see "Left turn only" signs mounted near the left turn protected signal overhead. Sometimes there's a no-U-Turn sign and sometimes there isn't. In California, the dual left turn signs will either show the inside turn lane with or without a U turn arrow as a spur off the left turn arrow. If there isn't one, the sign will show the text "NO U TURN" and a no U turn symbol will be mounted on the far left hand corner of the intersection.
Other states should use the California signage, otherwise it's vague whether a U-turn is allowed if there is not a sign specifically ruling it out.
Quote from: blawp on April 26, 2012, 11:57:02 PM
Other states should use the California signage, otherwise it's vague whether a U-turn is allowed if there is not a sign specifically ruling it out.
Wisconsin used to have the law, (the last in the nation I believe), where U-turns were illegal at
any signalized intersection, signed or not (very confusing to tourists). Since January 1, 2010, when the state statute was changed, U-turns are now permitted anywhere, unless there is a sign prohibiting it http://www.dot.wisconsin.gov/drivers/drivers/apply/types/law-changes-2010.htm (http://www.dot.wisconsin.gov/drivers/drivers/apply/types/law-changes-2010.htm). As the law states, the U-turn is only permitted from the left-most lane, so dual and triple left turn lanes are covered. I believe many other states have this or a similarly stated law as well, so I don't think additional signage is really needed in most cases.
Practice in Nevada at dual left turn lanes tends to be to have the sign show a LT/UT and LT arrow for the respective lanes. If no U-turn is allowed, then it is just 2 LT arrows on the sign which is accompanied by a symbolic No U-turn sign on the mast arm.
Nevada law is similar to Wisconsin in that U-turns are allowed at any intersection (as long as the turn can be done safely) unless a sign specifically prohibits it.
U turns are typically permitted either anywhere or only at controlled intersections under state law.
Illinois has some California-style left turn signage along North Avenue (IL-64), but usually it's just for the two left turn lanes, no U-Turn included or prohibited.
Quote from: kphoger on April 27, 2012, 02:19:46 PM
U turns are typically permitted either anywhere or only at controlled intersections under state law.
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
Quote from: empirestate on April 28, 2012, 12:41:03 AM
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
It's a law lots of people break, but in New York City it's illegal to make a U-turn anywhere on a divided highway. You can get a ticket for it.
Though, apparently, upon looking into it, this doesn't extend to the entire state as I had previously had the impression.
Quote from: Duke87 on April 28, 2012, 10:08:20 AM
Quote from: empirestate on April 28, 2012, 12:41:03 AM
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
It's a law lots of people break, but in New York City it's illegal to make a U-turn anywhere on a divided highway. You can get a ticket for it.
Though, apparently, upon looking into it, this doesn't extend to the entire state as I had previously had the impression.
Yes, only on divided highways and in business districts, and those only in NYC. You had me worried for a second, having made a lifetime's worth of U-turns all over the state!
(And also, by state law, on curves, hills and so forth where you can't see far enough away and where it would be stupid to bang a U-ey anyhow.)
I have an example of this type of sign as it is apparently common only in California:
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Ffarm9.staticflickr.com%2F8142%2F6956666336_2995181a57_c.jpg&hash=62ed61420eb6907e50faf173ea37b4d8500d46ef)
Please note the faded "NO U TURN" at the bottom of the sign.
Quote from: empirestate on April 28, 2012, 12:41:03 AM
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
I believe Chicago has this law as well; hence this sign on the Canal Street exit off the Ike:
http://g.co/maps/x5ama (http://g.co/maps/x5ama)
Quote from: kphoger on April 28, 2012, 12:54:49 PM
Quote from: empirestate on April 28, 2012, 12:41:03 AM
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
I believe Chicago has this law as well; hence this sign on the Canal Street exit off the Ike:
http://g.co/maps/x5ama (http://g.co/maps/x5ama)
Not so sure about that. U-Turns, IIRC, are permitted on boulevards and LSD (boulevard section). That's a special case where you have another two lanes to the left of the lane that can U-Turn.
Quote from: Brandon on April 28, 2012, 01:01:28 PM
Quote from: kphoger on April 28, 2012, 12:54:49 PM
Quote from: empirestate on April 28, 2012, 12:41:03 AM
Quote from: Duke87 on April 27, 2012, 10:15:27 PM
And then you have New York, where U-turns are prohibited except where signage indicates otherwise (which is rare).
Wait, huh?
I believe Chicago has this law as well; hence this sign on the Canal Street exit off the Ike:
http://g.co/maps/x5ama (http://g.co/maps/x5ama)
Not so sure about that. U-Turns, IIRC, are permitted on boulevards and LSD (boulevard section). That's a special case where you have another two lanes to the left of the lane that can U-Turn.
OK, so I looked it up. Apparently, the restriction only applies between and including Wacker Drive, Michigan Avenue, and Congress Parkway. Learn something new every day!
Quote from: CentralCAroadgeek on April 28, 2012, 11:31:52 AM
I have an example of this type of sign as it is apparently common only in California
That's an awesome mast arm.
Quote from: PennDOTFan on April 28, 2012, 01:48:04 PM
Quote from: CentralCAroadgeek on April 28, 2012, 11:31:52 AM
I have an example of this type of sign as it is apparently common only in California
That's an awesome mast arm.
Yea, it looks like it's wilting.
:spin:
Mike
Quote from: PennDOTFan on April 28, 2012, 01:48:04 PM
That's an awesome mast arm.
There are several of these mast arms here in Salinas. I don't know about elsewhere.
The mast arm looks like it's trying to do it's own U-turn :cool:
Shrug...that's a fairly common mast arm type in NorCal.
Quote from: empirestate on April 28, 2012, 10:52:34 AM
Quote from: Duke87 on April 28, 2012, 10:08:20 AM
It's a law lots of people break, but in New York City it's illegal to make a U-turn anywhere on a divided highway. You can get a ticket for it.
Though, apparently, upon looking into it, this doesn't extend to the entire state as I had previously had the impression.
Yes, only on divided highways and in business districts, and those only in NYC. You had me worried for a second, having made a lifetime's worth of U-turns all over the state!
Heh. My father learned to drive in NYC and to this day believes that U-turns like that on divided highways are illegal
everywhere in the entire country (hasty generalization), and he taught me such when he was teaching me how to drive. If I weren't interested in this sort of thing and looking it up, I wouldn't know better!
Quote from: blawp on April 29, 2012, 03:26:32 AM
Shrug...that's a fairly common mast arm type in NorCal.
Don't mean to thread-jack or anything, but does anyone know the rationale or thought process behind this mast-arm design? :confused: It looks like it would be a target for taller vehicles, especially with how far that left turn signal is below the other signal. Or, does it "droop" over a median island that the photo doesn't go low enough to show?
Quote from: DaBigE on April 29, 2012, 05:50:09 PM
Don't mean to thread-jack or anything, but does anyone know the rationale or thought process behind this mast-arm design? :confused: It looks like it would be a target for taller vehicles, especially with how far that left turn signal is below the other signal. Or, does it "droop" over a median island that the photo doesn't go low enough to show?
I've seen that it does "droop" over the median.
It usually hangs over a left turn only lane so nothing passes under it. Left turns are low speed approaches so you want the signal as close and as visible to the car in front as possible and less visible to thru traffic (hence the 3M signal).
Other states don't care about the intricacies of traffic signal design like California.
Quote from: blawp on April 29, 2012, 07:45:31 PM
It usually hangs over a left turn only lane so nothing passes under it.
Huh? It hangs over a lane of traffic, but
nothing passes under it? You have me confused...are these invisible vehicles?
Quote from: blawp on April 29, 2012, 07:45:31 PM
Other states don't care about the intricacies of traffic signal design like California.
Unless you mean that sarcastically, them fightin' words...:fight:
On the far side of the intersection it hangs. Wisconsin is a fairly good actor in signal design. I'm calling out states like Texas or Florida.
Quote from: blawp on April 29, 2012, 07:45:31 PM
Other states don't care about the intricacies of traffic signal design like California.
I beg to differ. They have different strategies for dealing with signal design, and how they use signals.
Worse strategies, generally. Such as...how can I save the most money while complying with the bare minimum requirements of the MUTCD.
Quote from: blawp on April 29, 2012, 08:28:02 PM
Worse strategies, generally. Such as...how can I save the most money while complying with the bare minimum requirements of the MUTCD.
No, different strategies. Illinois, for example, uses two left turn signals minimum regardless of number of turn lanes. There is always a side mounted signal, and a minimum of three signals per direction.
Personally, I thought the number of protected only left turns in California was nuts. We used a lot of protected/permitted lefts here in Illinois, which, IMHO, is superior to what CalTrans uses. And, personally, I think the clearing left turns used by MDOT (Michigan) are even better than that for traffic flow. But, of course, you don't need to worry about left turn signals when you don't have them on the biggest of roads such as Telegraph and Eight Mile. :sombrero:
Quote from: blawp on April 29, 2012, 07:56:08 PM
On the far side of the intersection it hangs.
Unless it's a T-intersection, you still have oncoming traffic that will pass under it (the opposing left turn or thru movement), and potentially the sloppy left turn movement from the cross-street. If you're going to mount the signal that low, you might as well go with a pedestal mount. If mounting the signal ~4-ft lower, why not simplify the arm and mount them all at the same level? IMO, this just looks sloppy.
Pedestal mounts in the median tend to get clobbered by cars.
Quote from: Brandon on April 29, 2012, 09:26:41 PM
Quote from: blawp on April 29, 2012, 08:28:02 PM
Worse strategies, generally. Such as...how can I save the most money while complying with the bare minimum requirements of the MUTCD.
No, different strategies. Illinois, for example, uses two left turn signals minimum regardless of number of turn lanes. There is always a side mounted signal, and a minimum of three signals per direction.
Personally, I thought the number of protected only left turns in California was nuts. We used a lot of protected/permitted lefts here in Illinois, which, IMHO, is superior to what CalTrans uses. And, personally, I think the clearing left turns used by MDOT (Michigan) are even better than that for traffic flow. But, of course, you don't need to worry about left turn signals when you don't have them on the biggest of roads such as Telegraph and Eight Mile. :sombrero:
Caltrans' statewide standard loop detection setup ensures motorists never wait too long for the arrow to change.
Quote from: blawp on April 29, 2012, 10:39:57 PM
Pedestal mounts in the median tend to get clobbered by cars.
Okay and so do mailboxes, and that is what insurance companies are for. It still does not answer my height clearance question. Nor does it give rationale for not mounting them all in the same relative level.
Quote from: CentralCAroadgeek on April 28, 2012, 02:37:28 PM
There are several of these mast arms here in Salinas. I don't know about elsewhere.
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Ffarm9.staticflickr.com%2F8142%2F6956666336_2995181a57_c.jpg&hash=62ed61420eb6907e50faf173ea37b4d8500d46ef)
I remember seeing these types of mast arms in the Sacramento area but not so much in the greater San Francisco Bay Area. I think these types of mast arms were developed to avoid having to mount a left turn signal in the middle of the street on an island and/or median. I don't know of any newer installations of this type of mast arm as the cities have gone to using a longer spanning mast arm and eliminating the island-mount signal (presumably because they tend to get knocked over and have to be replaced).
EDIT: Found some photos (actually GSV images) of some of the same type of mast arms both from the Sacramento area...
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.markyville.com%2Faaroads%2FSacramento.jpg&hash=7b59aa86d98026d03ea4c02034f0aa88ebc94869)
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.markyville.com%2Faaroads%2FSacramento2.jpg&hash=f56f0aeae8c4dc7d37962665550e22746efeece0)
Quote from: blawp on April 29, 2012, 10:41:18 PM
Quote from: Brandon on April 29, 2012, 09:26:41 PM
Quote from: blawp on April 29, 2012, 08:28:02 PM
Worse strategies, generally. Such as...how can I save the most money while complying with the bare minimum requirements of the MUTCD.
No, different strategies. Illinois, for example, uses two left turn signals minimum regardless of number of turn lanes. There is always a side mounted signal, and a minimum of three signals per direction.
Personally, I thought the number of protected only left turns in California was nuts. We used a lot of protected/permitted lefts here in Illinois, which, IMHO, is superior to what CalTrans uses. And, personally, I think the clearing left turns used by MDOT (Michigan) are even better than that for traffic flow. But, of course, you don't need to worry about left turn signals when you don't have them on the biggest of roads such as Telegraph and Eight Mile. :sombrero:
Caltrans' statewide standard loop detection setup ensures motorists never wait too long for the arrow to change.
We use one of two, either the loop (can get covered by ice and snow) or the infrared detector mounted on the mastarm (can be blocked by weather). The loop may not always detect a motorcycle whereas the detector can.
Quote from: Brandon on April 29, 2012, 11:14:05 PM
We use one of two, either the loop (can get covered by ice and snow) or the infrared detector mounted on the mastarm (can be blocked by weather). The loop may not always detect a motorcycle whereas the detector can.
IIRC, the loop detectors around here can sense a motorcycle and some cities have installed loop detectors in the bike lane to allow cyclists to be able to trigger the signal. Snow and ice isn't a problem in 2/3 of the state (which includes all of the major metropolitan areas).
Always attacking California...
Quote from: DaBigE on April 29, 2012, 11:01:34 PM
Quote from: blawp on April 29, 2012, 10:39:57 PM
Pedestal mounts in the median tend to get clobbered by cars.
Okay and so do mailboxes, and that is what insurance companies are for. It still does not answer my height clearance question. Nor does it give rationale for not mounting them all in the same relative level.
Insurance is costly on a routine event... In any case, I already explained to you that left turns are low-speed approaches, where the signal shall be most visible and closest to the car at the front of the line. Thru traffic is typically a high speed approach where the signal has to be visible to traffic well upstream of the intersection.
Quote from: myosh_tino on April 29, 2012, 11:11:51 PM
(https://www.aaroads.com/forum/proxy.php?request=http%3A%2F%2Fwww.markyville.com%2Faaroads%2FSacramento2.jpg&hash=f56f0aeae8c4dc7d37962665550e22746efeece0)
That left turn signal still doesn't look like it has enough clearance...maybe 12-ft? Does the extra ~4-ft really make that much of a difference in visibility?
Quote from: blawp on April 30, 2012, 12:36:29 AM
Insurance is costly on a routine event... In any case, I already explained to you that left turns are low-speed approaches, where the signal shall be most visible and closest to the car at the front of the line. Thru traffic is typically a high speed approach where the signal has to be visible to traffic well upstream of the intersection.
Speed of the approach has
NOTHING to do with
VERTICAL CLEARANCE. That has been my question/concern all along; tall vehicles being able to pass underneath.
Regardless, upstream visibility shouldn't be that much of a concern as a vehicle should not and cannot be taking the left turn at the posted speed limit anyway. If there is a concern with the first vehicle seeing the signal, you can either a) adjust the vertical angle of the suspended signal, or b) mount a supplementary signal on the far-left side, as many other states (including CA) do already. For the record, I never mentioned a
median-mounted pedestal signal.
Quote from: DaBigE on April 29, 2012, 09:56:55 PM
If you're going to mount the signal that low, you might as well go with a pedestal mount.
revisionist history, folks.
Quote from: DaBigE on April 30, 2012, 01:05:18 AM
That left turn signal still doesn't look like it has enough clearance...maybe 12-ft? Does the extra ~4-ft really make that much of a difference in visibility?
Not wanting to sound like a smart-ass but don't you think if there was a clearance problem, the city maintaining that signal would not install another just like it after the first got whacked by a truck or some other high-clearance vehicle?
Quote from: blawp on April 30, 2012, 12:30:34 AM
Always attacking California...
Only after you decided to attack the rest of the US and claim that California is somehow exceptional. Knock it off.
CalTrans has pluses and minuses, same as any other DOT.
Quote from: myosh_tino on April 30, 2012, 02:49:03 AM
Quote from: DaBigE on April 30, 2012, 01:05:18 AM
That left turn signal still doesn't look like it has enough clearance...maybe 12-ft? Does the extra ~4-ft really make that much of a difference in visibility?
Not wanting to sound like a smart-ass but don't you think if there was a clearance problem, the city maintaining that signal would not install another just like it after the first got whacked by a truck or some other high-clearance vehicle?
That thought crossed my mind as well. However, I know of a few municipalities that have signs and signals routinely knocked out and they keep replacing them in the same spot. Just drove past one of those spots on the way in this morning...knocked down yet again.
How about New Jersey... The state of NO LEFT TURNS... and therefore U turns... sometimes you see someone from out from out of state trying a U-Turn on a road with jughandles.
Quote from: jwolfer on May 09, 2012, 11:33:56 AM
How about New Jersey... The state of NO LEFT TURNS... and therefore U turns... sometimes you see someone from out from out of state trying a U-Turn on a road with jughandles.
You heard it here first! No left turns in New Jersey! :-D
Quote from: kphoger on May 09, 2012, 04:43:43 PM
Quote from: jwolfer on May 09, 2012, 11:33:56 AM
How about New Jersey... The state of NO LEFT TURNS... and therefore U turns... sometimes you see someone from out from out of state trying a U-Turn on a road with jughandles.
You heard it here first! No left turns in New Jersey! :-D
That would seriously complicate my commute
The Tucson area has pretty consistent signage when it comes to intersections with dual left turn lanes. Probably better than anywhere else in Arizona.
Speaking of dual left turns, are there a lot of places where there are permissive-protected dual left turns allowed? These signals are everywhere in the Tucson city limits. I supposed it works because the majority of signals in Tucson are lagging left. Most places outside the city limits would have permissive-protected dual left turns as an exception rather than the standard.
Quote from: swbrotha100 on June 25, 2012, 03:29:54 PM
Speaking of dual left turns, are there a lot of places where there are permissive-protected dual left turns allowed?
I can't think of any dual LT lanes in PA that aren't protected only. Of course that doesn't mean that some might not be found, but I'd bet it's rare.
Quote from: Mr_Northside on June 26, 2012, 03:32:57 PM
Quote from: swbrotha100 on June 25, 2012, 03:29:54 PM
Speaking of dual left turns, are there a lot of places where there are permissive-protected dual left turns allowed?
I can't think of any dual LT lanes in PA that aren't protected only. Of course that doesn't mean that some might not be found, but I'd bet it's rare.
There is one that I know of near the Auto Mall at the intersection of Bartram and Essington Avenues (http://goo.gl/maps/qb5x) in Philadelphia. This is actually the only permissive-protected dual left turn intersection that I'm aware of anywhere.
Quote from: PennDOTFan on June 26, 2012, 04:35:25 PM
Quote from: Mr_Northside on June 26, 2012, 03:32:57 PM
Quote from: swbrotha100 on June 25, 2012, 03:29:54 PM
Speaking of dual left turns, are there a lot of places where there are permissive-protected dual left turns allowed?
I can't think of any dual LT lanes in PA that aren't protected only. Of course that doesn't mean that some might not be found, but I'd bet it's rare.
There is one that I know of near the Auto Mall at the intersection of Bartram and Essington Avenues (http://goo.gl/maps/qb5x) in Philadelphia. This is actually the only permissive-protected dual left turn intersection that I'm aware of anywhere.
Anywhere in PA? I might buy that. But that's all I'll buy.
South Carolina has some on 278 near Hilton Head Island
Clark County, WA, uses ONLY signs for left turn indicating that a U-Turn is not permitted. They generally only use them if there's a green protected right for the orthogonal trafficflow.
Quote from: swbrotha100 on June 25, 2012, 03:29:54 PM
Speaking of dual left turns, are there a lot of places where there are permissive-protected dual left turns allowed? These signals are everywhere in the Tucson city limits. I supposed it works because the majority of signals in Tucson are lagging left. Most places outside the city limits would have permissive-protected dual left turns as an exception rather than the standard.
The only ones I know of in Minnesota are at the I-94/W Broadway interchange (1 for WB lefts onto SB ramp; 1 for NB ramp lefts onto Washington Ave) and at Valley View Rd and Prairie Center Dr (a new flashing yellow arrow signal with bimodal LED in the doghouse signals; the signal is permissive in the off-peak hours and split-phase in the peak hours).
MnDOT generally has forbidden protected-permissive dual lefts but apparently is warming to the idea. I heard from a guy at work that MnDOT is looking to install flashing yellow arrows at almost all new installations, even those with dual lefts.
As for the dual left signage, this sign (with the larger rightmost left arrow) is very common and is in the MN version of the MUTCD: http://goo.gl/maps/ywgE