traffic signal around a curve - installed on opposing mastarm

[agentsteel53]

I just drove this road the other day, and noticed an excellent solution to the problem of a traffic signal being around a curve: place it on the opposing mastarm, at the front of the intersection.

http://goo.gl/maps/p265x

as you can see, the mastarm has traffic signals for both directions.  this helps because the primary signals for southbound at that intersection are around a curve.

elsewhere, here is an example of an intersection that could use a traffic signal on the opposing mastarm.

http://goo.gl/maps/z9yW6

here, the google car was viewing this approach backwards, and the added parallax shows the red light behind the tree - westbound traffic in the correct lane would not see it until later, almost dangerously so.  this is an intersection that could benefit from another signal being placed on the opposing
mastarm.

[kphoger]

I've often thought that was needed here, at Hillside and 9th in Wichita.  Southbound traffic comes over a small hill on a gradual curve, and the only stoplights are pole-mounted.  There's a perfect spot for one on the opposite mastarm, which would be visible before any of the others.

[jeffandnicole]

Maybe I'm used to the Jersey way of doing things, but more often than not there's at least one signal over the opposing lanes.  In this case ( http://goo.gl/maps/qwCXI ) there's a signal on the far ground-mounted pole for the mastarm due to a curve in the road (exiting out of the street view reveals the curve in the road; the hazy street cam doesn't show the curve or the light very well from a distance)

[Big John]

That is frequently done in Georgia in those situations.

[Ian]

Pennsylvania does it a lot...


And in more extreme cases...

[M3019C LPS20]

I just drove this road the other day, and noticed an excellent solution to the problem of a traffic signal being around a curve: place it on the opposing mastarm, at the front of the intersection.

http://goo.gl/maps/p265x

as you can see, the mastarm has traffic signals for both directions.  this helps because the primary signals for southbound at that intersection are around a curve.

This kind of set-up is common throughout various locations of New Jersey, not to mention the suburbs of New York City.

Though I agree it is a good alternative, a motorist, at first, may confuse that individual traffic signal head as a permissive signal, since it appears to face the left turn lane. Though I am sure that he or she would soon see those protected left turn traffic signals that control the lane. If it were up to me, I would adjust the head, so that it would face the thru lanes. Just to prevent confusion.

[dfnva]

Virginia does this practice in some situations, but not others. 

Here is an interesting situation, both a supplemental protected left and through signal next to each other. Not necessarily the best set up, but better than no supplemental signals at this curve as it was before 2012.

http://goo.gl/maps/7EVN7 (SR-641/Old Bridge Rd at SR-906/Occoquan Rd in Lake Ridge, VA)

I like the practice of supplemental signals (one the left and right far corners; and, in IL, on the close right corner) as is done in many Midwestern and Southwestern states, which mitigates this issue to an extent.

[1995hoo]

Virginia does this practice in some situations, but not others. 

Here is an interesting situation, both a supplemental protected left and through signal next to each other. Not necessarily the best set up, but better than no supplemental signals at this curve as it was before 2012.

http://goo.gl/maps/7EVN7 (SR-641/Old Bridge Rd at SR-906/Occoquan Rd in Lake Ridge, VA)

I like the practice of supplemental signals (one the left and right far corners; and, in IL, on the close right corner) as is done in many Midwestern and Southwestern states, which mitigates this issue to an extent.

I can think of a place where Virginia's done that using span wire: http://goo.gl/maps/VC4IC  (Tysons Boulevard at Galleria Drive near Tysons II–the Google car only has an image from the other side of the road, but you can see the light well enough.) I remember the first time I encountered that left-turn light because I didn't even notice it up there–I was watching the other signals and only realized there was a left-turn light when Ms1995hoo said the light was green.

I've never known why they set it up that way, given that it isn't on a curve.

[Eth]

I never remembered seeing this when growing up in Georgia, but when I moved to Maryland I found that this was a common practice, and it struck me as brilliant. I now see it occasionally in Georgia, but not very often.

[WichitaRoads]

I've often thought that was needed here, at Hillside and 9th in Wichita.  Southbound traffic comes over a small hill on a gradual curve, and the only stoplights are pole-mounted.  There's a perfect spot for one on the opposite mastarm, which would be visible before any of the others.

Agreed. Always hated that light. We have one that kind of fits this category - 13th and North River Blvd. in Riverside... http://goo.gl/maps/osVuI

ICTRds

[kphoger]

I've often thought that was needed here, at Hillside and 9th in Wichita.  Southbound traffic comes over a small hill on a gradual curve, and the only stoplights are pole-mounted.  There's a perfect spot for one on the opposite mastarm, which would be visible before any of the others.

Agreed. Always hated that light. We have one that kind of fits this category - 13th and North River Blvd. in Riverside... http://goo.gl/maps/osVuI

ICTRds

Ah, yes, and just a few blocks from our friends' house.  Thanks for the example.

[deathtopumpkins]

The city of Hampton, VA did that a few years back when reconstructing the intersection of Fox Hill Rd (VA 169) and Woodland Rd:

http://goo.gl/maps/0SI36

[dfnva]

Virginia does this practice in some situations, but not others. 

Here is an interesting situation, both a supplemental protected left and through signal next to each other. Not necessarily the best set up, but better than no supplemental signals at this curve as it was before 2012.

http://goo.gl/maps/7EVN7 (SR-641/Old Bridge Rd at SR-906/Occoquan Rd in Lake Ridge, VA)

I like the practice of supplemental signals (one the left and right far corners; and, in IL, on the close right corner) as is done in many Midwestern and Southwestern states, which mitigates this issue to an extent.

I can think of a place where Virginia's done that using span wire: http://goo.gl/maps/VC4IC  (Tysons Boulevard at Galleria Drive near Tysons II–the Google car only has an image from the other side of the road, but you can see the light well enough.) I remember the first time I encountered that left-turn light because I didn't even notice it up there–I was watching the other signals and only realized there was a left-turn light when Ms1995hoo said the light was green.

I've never known why they set it up that way, given that it isn't on a curve.

I know I'm getting off topic, but that's the problem I see with the set up with some newer VDOT signal installations - protected left turn signal exclusively on the close side of the intersection and through signals on the far side. I don't like it, a redundant far side protected left turn signal (on a mast arm or pedestal) should be used as well.

Examples (which include, but are not limited to):
http://goo.gl/maps/06f1L  -- VA-253/Port Republic Rd and SR-726/Stone Spring Rd, Harrisonburg (Rockingham County)
http://goo.gl/maps/TkGHo  -- SR-650/Gallows Rd and I-495, Merrifield
http://goo.gl/maps/ot1Z3 --- SR-620/Braddock Rd and I-495, Springfield

At one time, such a situation existed here http://goo.gl/maps/zq8D1 (Old Lee Hwy and Layton Hall Dr, Fairfax) until about 1990. A protected left signal was on the close mast arm, a unique situation at the time. It was replaced by a doghouse signal installed on the far side mast arm (like the Google Streetview, though, these are second generation signals/mast arms).

-Dan

[KEK Inc.]

Washington does this all the time, but it's more common to be placed on the parent mast, rather than the mast arm.

Signal on mast-arm: 
http://goo.gl/maps/H5tFU

Signal on main mast: 
http://goo.gl/maps/43oec
http://goo.gl/maps/vfJ3C

Both!:
http://goo.gl/maps/OfSR4

[Brandon]

I've seen a few of these in Illinois, although not always mounted on the mastarms.

Pekin, IL, with flashing yellow arrows

[ET21]

I've seen a few of these in Illinois, although not always mounted on the mastarms.

Pekin, IL, with flashing yellow arrows

It seems there used alot when they redo major intersections. Great example would be US 6 (159th street) and US 45 (LaGrange Road), where is used to be only one mastarm. Now they have a double oncoming there and building another one up the road at 143rd and 141st

[roadman65]

Kissimmee, FL and Orlando, FL are starting to adopt this practice.

New Jersey always had done this and PA is starting to do it in certain places.

What is needed is flashing signal ahead warnings before curves in many places.  Sometimes even a left side head is not even visible until you are half way or more around the curve.  Considering that most people nowadays do not drive safely and road rage is a norm a lot of the times, it would be a safe practice to impliment.

[1995hoo]

Kissimmee, FL and Orlando, FL are starting to adopt this practice.

New Jersey always had done this and PA is starting to do it in certain places.

What is needed is flashing signal ahead warnings before curves in many places.  Sometimes even a left side head is not even visible until you are half way or more around the curve.  Considering that most people nowadays do not drive safely and road rage is a norm a lot of the times, it would be a safe practice to impliment.

I think what I would like more than just "signal ahead" is one that does "red light ahead when flashing." That way if the light is around a blind curve you know to expect stopped traffic. A mere "signal head" doesn't tell you whether the light's red or green.

[agentsteel53]

the worst is that some states have the flashing yellow lights at the sign mean "signal about to turn yellow - prepare to stop", while others have it mean "yep, that's a traffic signal all right".

[KEK Inc.]

You could have Prepare to Stop warning signs. 

California:




Alaska:


British Columbia:




Australia:

[deathtopumpkins]

I personally am fond of Maryland's signs:

[jeffandnicole]

A typical design in NJ, which 'RED' would flash in the box (alternating with the always visible 'Signal Ahead') when the light is about to turn red, or is red.

http://goo.gl/maps/JEiB7

I never cared for this one (the image is poor, I know) on Rt. 4/7 in the Newport, DE area.  http://goo.gl/maps/59SgW .  The lights would flash only when the actual traffic light turned yellow (and then red) rather than in advance of the yellow, so quite frequently drivers will pass under the unlit sign, only to find the light turning red as they rounded the curve.

[Roadsguy]

I personally am fond of Maryland's signs:

That, but usually on a mast arm, is exactly what PennDOT does.

[kphoger]

Most of the advance warning signs like that I've seen are due to the high speed of traffic, not due to the curvature of the road.

At any rate, with or without advance warning sign, the point remains that a stoplight is often more visible to the approach when it's attached to the opposite mastarm.

[pctech]

I've seen a signal mounted on the vertical support of traffic signal on the opposite side of the street here, but not on the horizontal mast. We has yellow diamonds signs that read prepare to stop when flashing at "blind spots" for signals.

Mark