Span Wire Vs Mast Arm

[kphoger]

My apologies to anyone who was offended.

I'm doing better already, and I only have three more sessions of therapy to go.

[SkyPesos]

Why choose between span wire and mast arms when you can have both in an intersection, like this one in Cincinnati's downtown : p

[SignBridge]

My apologies to anyone who was offended.

I'm doing better already, and I only have three more sessions of therapy to go.

LOL Good to hear you're doing so well. I hope Jakeroot is making as good or better recovery. LOL

[jakeroot]

I've recovered

[democratic nole]

However, in any sort of urban core environment, you really need mast arms.

That was my main point about the Seattle signals. It is maybe the only large city I am aware of where span wire seems to be the prevalent installation mode for signals in a downtown area. I don't know how they could ever allow https://goo.gl/maps/bRdnHPo8v6diWsZd9

There are definitely more examples than just Seattle. Vancouver, BC has an extensive amount of span wire in their downtown. Both Seattle and Vancouver have plenty of mast arms as well. The use of span wire is by no means close to a universal practice in either city. Where I live, in Tacoma, another large PNW city, span wire is also very prevalent throughout the downtown core.

There are many reasons why span wire is preferred in urban areas:

(1) easier to modify later if lane layouts change
(2) easier to work into trolley wire setups (esp. important in Vancouver and Seattle)
(3) mast arms are bulky and can be inappropriate in tighter urban areas. Small mast arms, like in Spokane, WA, are a good compromise.
(4) mast arms do nothing to improve signal visibility, which is better achieved through backplates (which Seattle makes extensive use of).

In downtown Seattle and downtown Vancouver, span wire likely became popular early on because overhead signals showed up pretty quickly over a short period of time, mostly in the 70s and 80s, and the cost to implement overhead signals with mast arms would have far exceeded most budgets given the sheer number of signalized intersections. Few modifications have taken place since then, so span wire remains common. This is especially true in Vancouver, where most signals are post-mounted and where the span wire signals were mostly added only to aid in signal visibility.

It should be noted that both cities have plenty of mast arms. Both old and new examples of both can be found throughout each city. In Downtown Seattle, a large number of intersections use only post mounted signals. Many signals that are not post mounted, such as those along 2nd Ave and 5th Ave, are mast arms. Never mind the huge number of mast arms outside of the downtown area.

Basically: don't rag on Seattle because (A) they're not unique in using span wire, (B) they have good reasons to use it, and (C) many intersections don't use span wire anyway.

Couple other things, too: new span wire is hard to come by in WA no matter where you are. Many cities have never used it. Additionally, in that above photo quote (original quote from me), the only intersection in that picture with span wire is from Missouri, and the other two pictures are not from Seattle. What in the hell made you bring up Seattle?

As to the comments above about politics: get the f*** out of here with that shit. It has nothing to do with traffic lights.

This is a good post and appreciate the detail. A couple of points:
-- When I was speaking of major cities with span wire signals downtown, I was speaking of North America. Seattle is unique among big cities that I have been by having prevalent span wire use in a downtown core. You will not see span wire in downtown Chicago, Los Angeles, Phoenix, etc. You do not see them used in most other countries, even developing ones. Pedestal mounts or overhead mastarms are pretty universal outside of North America elsewhere that I have seen.
-- Cities like Boston and San Francisco seem to have no issue using overhead mastarms where streetcar wires are present.

I have long been reading about municipalities make up interesting excuses for why they do not use mastarm signals. This 1988 article from the Washington Post is always one I have enjoyed: https://www.washingtonpost.com/archive/local/1988/06/10/in-california-easy-to-see-traffic-signals-and-street-signs-are-no-dream/5578117f-5420-4d07-a71b-28afd27c39dc/. To quote:
Most of Northern Virginia's signals are controlled by the state, which has long preferred span wires. Anne Didden, the state's area engineer on this subject, says they are about $20,000 cheaper and easier to install. Mast arms require undergound wiring and that can get complicated and expensive because underground utilities sometimes have to be worked around, she said. Asked how California, with 25 million people, seems to surmount this problem and put mast arm signals all over the state, Didden said, "Interesting question."

Many municipalities were using the guy-wire mastarms as early as the 50's. Here's footage driving down Sunset Blvd. in Los Angeles in 1963 where overhead guy-wire signals are standard:. About the 1:20 mark forward, you can see what appears to be maybe one of the first left-turn signals at Doheny Drive. Modern mastarms came into use sometime in the 1970's I believe. You can see some in Las Vegas in the 70's at about the 1:15 mark: https://www.youtube.com/watch?v=9Xt7j3BKUpI.

My beef is not with Seattle. I just don't think they should use span wire signals in the downtown core. My main beef is with span wire signals generally. I don't think they should be used ever and states like California, Nevada, and Illinois reinforce my viewpoint on that. Florida's continued use of span wire given the threat of hurricane winds is embarrassing. However, even the ones they do install are often terrible. Tampa, where I live, has taken to installing diagonal mastarms that are atrocious and have poor visibility for certain approaches to the intersection. https://goo.gl/maps/q4JqALvwBR4frt5A6

[roadman65]

However, in any sort of urban core environment, you really need mast arms.

https://goo.gl/maps/NpzScGRasRfnqtp17

That was my main point about the Seattle signals. It is maybe the only large city I am aware of where span wire seems to be the prevalent installation mode for signals in a downtown area. I don't know how they could ever allow https://goo.gl/maps/bRdnHPo8v6diWsZd9

There are definitely more examples than just Seattle. Vancouver, BC has an extensive amount of span wire in their downtown. Both Seattle and Vancouver have plenty of mast arms as well. The use of span wire is by no means close to a universal practice in either city. Where I live, in Tacoma, another large PNW city, span wire is also very prevalent throughout the downtown core.

There are many reasons why span wire is preferred in urban areas:

(1) easier to modify later if lane layouts change
(2) easier to work into trolley wire setups (esp. important in Vancouver and Seattle)
(3) mast arms are bulky and can be inappropriate in tighter urban areas. Small mast arms, like in Spokane, WA, are a good compromise.
(4) mast arms do nothing to improve signal visibility, which is better achieved through backplates (which Seattle makes extensive use of).

In downtown Seattle and downtown Vancouver, span wire likely became popular early on because overhead signals showed up pretty quickly over a short period of time, mostly in the 70s and 80s, and the cost to implement overhead signals with mast arms would have far exceeded most budgets given the sheer number of signalized intersections. Few modifications have taken place since then, so span wire remains common. This is especially true in Vancouver, where most signals are post-mounted and where the span wire signals were mostly added only to aid in signal visibility.

It should be noted that both cities have plenty of mast arms. Both old and new examples of both can be found throughout each city. In Downtown Seattle, a large number of intersections use only post mounted signals. Many signals that are not post mounted, such as those along 2nd Ave and 5th Ave, are mast arms. Never mind the huge number of mast arms outside of the downtown area.

Basically: don't rag on Seattle because (A) they're not unique in using span wire, (B) they have good reasons to use it, and (C) many intersections don't use span wire anyway.

Couple other things, too: new span wire is hard to come by in WA no matter where you are. Many cities have never used it. Additionally, in that above photo quote (original quote from me), the only intersection in that picture with span wire is from Missouri, and the other two pictures are not from Seattle. What in the hell made you bring up Seattle?

As to the comments above about politics: get the f*** out of here with that shit. It has nothing to do with traffic lights.

This is a good post and appreciate the detail. A couple of points:
-- When I was speaking of major cities with span wire signals downtown, I was speaking of North America. Seattle is unique among big cities that I have been by having prevalent span wire use in a downtown core. You will not see span wire in downtown Chicago, Los Angeles, Phoenix, etc. You do not see them used in most other countries, even developing ones. Pedestal mounts or overhead mastarms are pretty universal outside of North America elsewhere that I have seen.
-- Cities like Boston and San Francisco seem to have no issue using overhead mastarms where streetcar wires are present.

I have long been reading about municipalities make up interesting excuses for why they do not use mastarm signals. This 1988 article from the Washington Post is always one I have enjoyed: https://www.washingtonpost.com/archive/local/1988/06/10/in-california-easy-to-see-traffic-signals-and-street-signs-are-no-dream/5578117f-5420-4d07-a71b-28afd27c39dc/. To quote:
Most of Northern Virginia's signals are controlled by the state, which has long preferred span wires. Anne Didden, the state's area engineer on this subject, says they are about $20,000 cheaper and easier to install. Mast arms require undergound wiring and that can get complicated and expensive because underground utilities sometimes have to be worked around, she said. Asked how California, with 25 million people, seems to surmount this problem and put mast arm signals all over the state, Didden said, "Interesting question."

Many municipalities were using the guy-wire mastarms as early as the 50's. Here's footage driving down Sunset Blvd. in Los Angeles in 1963 where overhead guy-wire signals are standard:. About the 1:20 mark forward, you can see what appears to be maybe one of the first left-turn signals at Doheny Drive. Modern mastarms came into use sometime in the 1970's I believe. You can see some in Las Vegas in the 70's at about the 1:15 mark: https://www.youtube.com/watch?v=9Xt7j3BKUpI.

My beef is not with Seattle. I just don't think they should use span wire signals in the downtown core. My main beef is with span wire signals generally. I don't think they should be used ever and states like California, Nevada, and Illinois reinforce my viewpoint on that. Florida's continued use of span wire given the threat of hurricane winds is embarrassing. However, even the ones they do install are often terrible. Tampa, where I live, has taken to installing diagonal mastarms that are atrocious and have poor visibility for certain approaches to the intersection. https://goo.gl/maps/q4JqALvwBR4frt5A6

Baltimore is another city to use span wires in the Downtown Area. Even with all the other parts of the state going mast arms, the city is not changing with it.

As far as underground wiring goes, NJ has mast arms with overhead wires as power supply. Cranford was one of them before Union County replaced them with their own mono tube arms using underground conduits. I don’t know why it can’t be done like that in VA.
https://goo.gl/maps/NpzScGRasRfnqtp17

[kphoger]

My main beef is with span wire signals generally. I don't think they should be used ever and states like California, Nevada, and Illinois reinforce my viewpoint on that. Florida's continued use of span wire given the threat of hurricane winds is embarrassing.

I think we've had this conversation before, but it was several years ago.  Are span-wire installations more hurricane-resistant?  That's what I told my sons the other day in the car during a conversation prompted by driving through a span-wire intersection.

[democratic nole]

My main beef is with span wire signals generally. I don't think they should be used ever and states like California, Nevada, and Illinois reinforce my viewpoint on that. Florida's continued use of span wire given the threat of hurricane winds is embarrassing.

I think we've had this conversation before, but it was several years ago.  Are span-wire installations more hurricane-resistant?  That's what I told my sons the other day in the car during a conversation prompted by driving through a span-wire intersection.

As far as I have seen, the answer is no. To quote from this 1998 article: https://news.ufl.edu/archive/1998/05/new-dampener-makes-traffic-light-poles-safer-longer-lasting.html
"[Mastarms] are becoming more common in Florida after proving far more reliable than traditional cable-suspended lights during Hurricane Andrew in 1992. State officials said only one was damaged, while more than 2,700 cable-suspended signals broke off and fell, said Ron Cook, a civil engineering professor and co-investigator on the UF project with civil engineering Professor Dave Bloomquist. The DOT now requires the structures at new intersections or intersections where traffic lights are replaced within 10 miles of the coast."

FDOT has changed the installs of mastarms to make them more wind resistant, but I have not seen any data that says they can withstand high winds in the way that mastarm signals can. Here's a picture from the hurricanes in Lafayette, LA this year that is encapsulates why communities should use mastarms:

Notice that the mastarm signals survived essentially without issue, while all of the above ground telephone poles failed.

I find it appalling that FDOT does not have a universal mastarm standard here in Florida. Rather than do things right the first time, they would apparently rather be cheap and be forced to spend more money over the long run by having to replace these trash span wire assemblies when they fail. FDOT can whine about cost all it wants, but plenty of other low tax jurisdictions (Nevada, Arizona, the Dakotas, etc.) have universal mastarm installation without issue.

[RobbieL2415]

The only place I know of around here where span wires are rare is Cape Cod. It's mostly ground-mounted signals with a few mast arms for bigger intersections. I think it has to do with wind resistance.

[ErmineNotyours]

As far as underground wiring goes, NJ has mast arms with overhead wires as power supply. Cranford was one of them before Union County replaced them with their own mono tube arms using underground conduits. I don't know why it can't be done like that in VA.
https://goo.gl/maps/NpzScGRasRfnqtp17

That intersection doesn't have any pedestrian signals, and new installations require it.  You would have to have mast arms wrap three fourths the way around the entire intersection to cover all the posts for above ground wiring for ped signals.  I think I have seen installations like that and they are odd looking.

[jakeroot]

[clipped]

This is a good post and appreciate the detail. A couple of points:
-- When I was speaking of major cities with span wire signals downtown, I was speaking of North America. Seattle is unique among big cities that I have been by having prevalent span wire use in a downtown core. You will not see span wire in downtown Chicago, Los Angeles, Phoenix, etc. You do not see them used in most other countries, even developing ones. Pedestal mounts or overhead mastarms are pretty universal outside of North America elsewhere that I have seen.
-- Cities like Boston and San Francisco seem to have no issue using overhead mastarms where streetcar wires are present.

Couple of things here: mast arms, like those in the US, are a fairly unique American invention. Big mast arms with several signals on them, hanging over the street, isn't really something seen in other countries. Other countries use mast arms to mount overhead signals, but it's usually just one, maybe two; most signals are mounted using posts. The Netherlands and perhaps China are two unique cases, where overhead signals seem very common. Japan only uses overhead signals, but they only use one per mast arm (per direction...usually two are mounted back-to-front), so they're not especially bulky.

Basically: if you're asking for stuff like this (in Seattle, by the way!), you're asking for something not really seen outside the US. Outside the US, this image shows more common practices.

On overhead wires: Here in Seattle, as in Vancouver, many buses are trolleybuses. They rely on overhead catenary to supply electricity, like streetcars, but there are far more lines than most cities with streetcar systems, so overhead wiring is common throughout the city. It's not that it's impossible to use trolleybus catenary (this image clearly shows how it would work), it's just that it wasn't super common to integrate mast arms with overhead trolleybus wire. However, the practice has changed and Seattle does use overhead mast arms now, as I've already said, even at major intersections like this where trolleybuses and streetcars mix.

[SkyPesos]

Couple of things here: mast arms, like those in the US, are a fairly unique American invention. Big mast arms with several signals on them, hanging over the street, isn't really something seen in other countries. Other countries use mast arms to mount overhead signals, but it's usually just one, maybe two; most signals are mounted using posts. The Netherlands and perhaps China are two unique cases, where overhead signals seem very common. Japan only uses overhead signals, but they only use one per mast arm (per direction...usually two are mounted back-to-front), so they're not especially bulky.

There’s a picture I posted on an unrelated topic thread with a mast arm in China on it (https://www.aaroads.com/forum/index.php?topic=28175.0). In that picture, you have one signal for each direction, unlike here in the US, where it’s generally one per lane. But Chinese Cities can get inconsistent about this. Fuzhou (the city in that thread) is all one signal per direction, but I’ve seen roads in Beijing and Shenzhen where one signal set can have one per lane, with a really long mast arm, then the next set on that road is one per direction.

[marleythedog]

Why choose between span wire and mast arms when you can have both in an intersection, like this one in Cincinnati's downtown : p

Those mast arms happened when the streetcar was put in, though I'm curious why they didn't do the usual downtown style. Cost, perhaps, since the streetcar went so far over?

[marleythedog]

I'll be the contrarian that favors span wires.

* I believe someone in an earlier post estimated that mast arms add around $20k to a signal project. When cities convert entire neighborhoods or downtowns to mast arm, that's hundreds of thousands of dollars not going to crumbling roads, bridges, or--since aesthetics do matter--meaningful improvements like plants/trees, sidewalks, lighting, benches, that improve the aesthetics for people (not just cars).
* Span wires are much more subtle than mast arms visually (especially the massive "tree trunks" on modern setups). The signals themselves can still be perfectly visible by adding backplates, and top and bottom wires keep them from whipping around.
* Say a boom truck takes out a signal. With span wire, the harm to passersby is the weight of the signals falling and the risk of getting tangled up in the wires. When that mast arm comes down, that's a lot larger surface area to kill somebody.
* I will admit that mast arms probably hold up better to hurricanes and tornadoes than span wires. They just look freaky as hell flexing up and down in the wind.

Ohio was almost exclusively span wire until the 21st century. Now, jurisdictions are practically tripping over themselves to replace them with mast arms, and I haven't figured out why.

From another thread:

Another reason I prefer mastarms to span wire:

https://www.reddit.com/r/MontgomeryCountyMD/comments/kkqrrd/what_i_encountered_on_my_way_to_work_today_at/

https://i.imgur.com/8hZEuZc.jpg

Span wire signals can be hung right back up in a day or two, though. After a recent tornado nearby, crews got the span wires hung back up in a day and the damaged signal heads replaced a day or two after that. If something takes out a mast arm, you'd have to set up a temporary span wire, potentially set some temporary poles, and wire it all in, while you order a new mast arm to arrive in what, weeks?

Edit: If someone can show that TCO of a mast arm is lower, despite the higher initial cost, I might be more amenable to them. I'm not an engineer, so maybe I'm missing something.

[democratic nole]

[clipped]

This is a good post and appreciate the detail. A couple of points:
-- When I was speaking of major cities with span wire signals downtown, I was speaking of North America. Seattle is unique among big cities that I have been by having prevalent span wire use in a downtown core. You will not see span wire in downtown Chicago, Los Angeles, Phoenix, etc. You do not see them used in most other countries, even developing ones. Pedestal mounts or overhead mastarms are pretty universal outside of North America elsewhere that I have seen.
-- Cities like Boston and San Francisco seem to have no issue using overhead mastarms where streetcar wires are present.

Couple of things here: mast arms, like those in the US, are a fairly unique American invention. Big mast arms with several signals on them, hanging over the street, isn't really something seen in other countries. Other countries use mast arms to mount overhead signals, but it's usually just one, maybe two; most signals are mounted using posts. The Netherlands and perhaps China are two unique cases, where overhead signals seem very common. Japan only uses overhead signals, but they only use one per mast arm (per direction...usually two are mounted back-to-front), so they're not especially bulky.

Basically: if you're asking for stuff like this (in Seattle, by the way!), you're asking for something not really seen outside the US. Outside the US, this image shows more common practices.

On overhead wires: Here in Seattle, as in Vancouver, many buses are trolleybuses. They rely on overhead catenary to supply electricity, like streetcars, but there are far more lines than most cities with streetcar systems, so overhead wiring is common throughout the city. It's not that it's impossible to use trolleybus catenary (this image clearly shows how it would work), it's just that it wasn't super common to integrate mast arms with overhead trolleybus wire. However, the practice has changed and Seattle does use overhead mast arms now, as I've already said, even at major intersections like this where trolleybuses and streetcars mix.

I think a point I was trying to make which was lost in translation is that it is a lie when certain state DOT's say that certain intersections require span wire installations as opposed to mastarms. Nowhere else in the world (that I am aware of) makes regular use of span wire installations, even in developing countries, which somewhat reinforces my point regarding their inadequacy for use in this country. The signals from Sydney you posted are very similar to the standard California signal installation, which I find to be superior to almost all other installs.

[democratic nole]

Edit: If someone can show that TCO of a mast arm is lower, despite the higher initial cost, I might be more amenable to them. I'm not an engineer, so maybe I'm missing something.

I don't have the data for this on a whole, but here is a Florida example: https://news.ufl.edu/archive/1998/05/new-dampener-makes-traffic-light-poles-safer-longer-lasting.html. Miami-Dade went to universal mastarm installation after Hurricane Andrew because they only one mastarm in the county was damaged, while 2,700 span wire signals were damaged. Broward County lost 60% of their signals during a 2004 hurricane because they were predominately span wire. When cities and states are regularly having to replace failed signals, that increases costs.

Anecdotally, I have driven around parts of Nevada, Arizona, and California that have mastarms installed decades ago that are still holding up well. For example, here's a Las Vegas signal outside of Circus Circus casino on Las Vegas Blvd. in 2020 https://goo.gl/maps/2xhSZEUAqxD28u7M9 versus 1978 (I think) https://i.pinimg.com/originals/65/d9/cd/65d9cda0864f6dbd9634826084ab7232.jpg. When you are talking about getting 40-50 years out of a traffic signal setup, that's pretty good. Los Angeles still has many guy-wire mastarms that were installed in the 60's in use. While I can't speak for other jurisdictions, Florida has spent a lot of money replacing span wire installations either due to failure in high-winds/hurricanes, or functional obsolescence. Rarely does one see signals here that have been in place for 40+ years. Almost all have been replaced with new span wire signals or mastarm signals.

[SignBridge]

I completely agree with democratic nole that California is the benchmark for good quality traffic signal installations. Nevada runs a close second though.

[EpicRoadways]

Span wire signals can be hung right back up in a day or two, though. After a recent tornado nearby, crews got the span wires hung back up in a day and the damaged signal heads replaced a day or two after that. If something takes out a mast arm, you'd have to set up a temporary span wire, potentially set some temporary poles, and wire it all in, while you order a new mast arm to arrive in what, weeks?

In my area, common practice seems to be to install a temporary mast arm when one is knocked down, generally one left over from an older intersection.

Anecdotally, I have driven around parts of Nevada, Arizona, and California that have mastarms installed decades ago that are still holding up well. For example, here's a Las Vegas signal outside of Circus Circus casino on Las Vegas Blvd. in 2020 https://goo.gl/maps/2xhSZEUAqxD28u7M9 versus 1978 (I think) https://i.pinimg.com/originals/65/d9/cd/65d9cda0864f6dbd9634826084ab7232.jpg. When you are talking about getting 40-50 years out of a traffic signal setup, that's pretty good. Los Angeles still has many guy-wire mastarms that were installed in the 60's in use. While I can't speak for other jurisdictions, Florida has spent a lot of money replacing span wire installations either due to failure in high-winds/hurricanes, or functional obsolescence. Rarely does one see signals here that have been in place for 40+ years. Almost all have been replaced with new span wire signals or mastarm signals.

Another thing that people often forget about with mast arms is that they can be reused almost as often as span wire signals as long as it isn't some weird skewed intersection with custom masts. Pretty much any time mast arms can be reused, they are (at least in my area). Typically an installation has to be at least 40 or 50 years old or there has to be a major reconstruction project that significantly alters the footprint of the intersection for the masts to be replaced outright. For example, this traffic signal (which wasn't very old) was replaced with a roundabout so three of the four mast arms got reused here, albeit with slightly different signal components. I'm sure this practice of reusing masts differs by jurisdiction, and some areas definitely seen more keen on it than others, but at least it can be done if $$ are a concern.

[SkyPesos]

Going to mention a state that I lived in for 10 years and generally find to be very consistent with signal installations (mast arms, specifically): Missouri. If California is the gold standard for mast arms, I'll say that Missouri is just a hair below that.
Generally, the state uses a plain, straight mast arm. Another example. Kansas City and St. Louis have their own variants; KC has something similar to California's mast arms with the curve, and St. Louis has this style on its older mast arms (idk what the best way to describe it), but it seems like they're switching to the MoDot standard. They also have mast arms with the ground support pole in the median; probably the only state I know that does that.

But for the very small number of permanent span wire installations MoDot uses, though, they look hideous. Here's an example of MO 141 and Ladue before the former got moved to a freeway in 2012

[jeffandnicole]

If something takes out a mast arm, you'd have to set up a temporary span wire, potentially set some temporary poles, and wire it all in, while you order a new mast arm to arrive in what, weeks?

Due to the typical placement of NJ's mast arms, they are relatively often taken down by a tractor trailer turning tightly or a vehicle hitting it pretty good.

The time to fully repair it is usually hours, not some theoretical long term project you're guessing at.

The pole and mast are usually reusable, and a bucket truck or lift contraption can often lift it back into place. The trucks that respond to these incidents have spare signals on them to replace any that were destroyed in the crash. The employees are on call to respond to such incidents.

For larger incidents, there are contractors on call that can replace a signal structure within hours as well.

[Scott5114]

I'm guessing there's something wonky about NJ's signal placement that makes that an ongoing concern. I can't think of any failing around here that weren't due to a strong tornado, and in that situation, not only would a span wire fare just as badly, you are going to have way bigger problems to worry about than a missing traffic signal.

(If a tornado is bad enough, top priority becomes getting street blades up–when those are missing and there are no extant buildings to use as landmarks, it becomes next to impossible for insurance adjusters and cleanup contractors to find addresses they're needed at. After the 2013 Moore tornado, Norman actually donated a batch of signs to make the process quicker.)

[jakeroot]

Just to explain something that might not have been made earlier: I much prefer mast arms to span wire. Assuming they aren't too bulky. California, Illinois, and BC have excellent standards that I wish more places adopted. My defence of places like Seattle and Vancouver was out of respect for considerations that might not necessarily be obvious when simply looking through the windshield of your car. I would love for Seattle to eventually phase out mast arms, but I also recognize that they are bulkier than span wire and are not exactly attractive in tight urban areas. Wires are common in cities so, by all accounts, mast arms are the odd thing. My overall preference in downtown cores is for post-mounted signals only, but I suppose that's not a typical preference.

[mrsman]

^^^^^

Post mounted would work great as being non-obstrusive and is my recommendation as well for narrower streets.

The problem, of course, on wider streets is that if you are driving in the middle of a very wide street, you may not even see the signal.

Washington DC and San Francisco are two cities that come to mind with extensive use of post mounted and very little mast arm usage.  Chicago also has a lot of signals in the loop without mast arms, but almost every signal outside of the loop has them. 

More and more signals in DC are getting mast arms, but the arms are very short.  Due to aesthetic issues, certain streets in the core do not have mast arms at all, even very wide streets like Pennsylvania, Constitution, and Independence.

IMO, skipping mast arms works fine where streets are narrow like here:

https://www.google.com/maps/@38.8876148,-77.0006817,3a,75y,89.3h,90.48t/data=!3m6!1e1!3m4!1sjfOe5UzkX2To3PkK4ZVK4Q!2e0!7i16384!8i8192

but not fine for here:

https://www.google.com/maps/@38.8874352,-77.0218142,3a,75y,331.59h,93t/data=!3m7!1e1!3m5!1sTLPHCC7C22zV2bAE45_G2Q!2e0!6s%2F%2Fgeo3.ggpht.com%2Fcbk%3Fpanoid%3DTLPHCC7C22zV2bAE45_G2Q%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D106.30299%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192

[jeffandnicole]

I'm guessing there's something wonky about NJ's signal placement that makes that an ongoing concern.

They're just placed way too close to the roadway.  Trucks making tight right turns often can snag it, or a crash within the intersection can send a car into it. 

I'll use a few examples here:
https://goo.gl/maps/qfZdj2WSL6sYhZL88 (right turns are now banned at this particular intersection due to this light pole being hit, but the movement can be made at the previous intersection).  https://goo.gl/maps/Fs19Pnv8FR28gQ3u9
https://goo.gl/maps/5cf48w2pKgAA4iFY9

(BTW, I specifically posted these 3 because they've all been hit, numerous times.  The pole and masts are still reused...only the light itself may have been replaced.  In all cases, the repairs were done same day.

[democratic nole]

^^^^^

Post mounted would work great as being non-obstrusive and is my recommendation as well for narrower streets.

The problem, of course, on wider streets is that if you are driving in the middle of a very wide street, you may not even see the signal.

Washington DC and San Francisco are two cities that come to mind with extensive use of post mounted and very little mast arm usage.  Chicago also has a lot of signals in the loop without mast arms, but almost every signal outside of the loop has them. 

More and more signals in DC are getting mast arms, but the arms are very short.  Due to aesthetic issues, certain streets in the core do not have mast arms at all, even very wide streets like Pennsylvania, Constitution, and Independence.

IMO, skipping mast arms works fine where streets are narrow like here:

https://www.google.com/maps/@38.8876148,-77.0006817,3a,75y,89.3h,90.48t/data=!3m6!1e1!3m4!1sjfOe5UzkX2To3PkK4ZVK4Q!2e0!7i16384!8i8192

but not fine for here:

https://www.google.com/maps/@38.8874352,-77.0218142,3a,75y,331.59h,93t/data=!3m7!1e1!3m5!1sTLPHCC7C22zV2bAE45_G2Q!2e0!6s%2F%2Fgeo3.ggpht.com%2Fcbk%3Fpanoid%3DTLPHCC7C22zV2bAE45_G2Q%26output%3Dthumbnail%26cb_client%3Dmaps_sv.tactile.gps%26thumb%3D2%26w%3D203%26h%3D100%26yaw%3D106.30299%26pitch%3D0%26thumbfov%3D100!7i16384!8i8192

Agree with this post. DC would benefit from the installation of pedestal mounted signals on the near side of the intersection (because they do not permit mastarms for aesthetic reasons).