Roundabout safety with 2 phase traffic light

[yand]

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.
I like the idea of a 2 phase traffic light: one pedestrian phase where all cars are stopped, and then a cars phase where the intersection acts as a regular unsignalized intersection. For a roundabout you could even only have traffic lights at the entry points for cars, and just time the lights so that the roundabout would generally be expected to be empty by the time pedestrians get the green light. Alternatively, exiting cars could get a flashing red during the pedestrian phase.
I know that many US intersections use the unsignalized phase at night, where (I am assuming) you can activate the pedestrian phase by pressing the button, but are there any examples of intersections that solely use the traffic light as a pedestrian safety device without ever having protected phases for cars, and are there signalized roundabouts that aren't horrible traffic circles?

[hotdogPi]

1. It's harder to get into a roundabout if you begin stopped.
2. It shouldn't be hard to cross as a pedestrian, as you're effectively crossing a series of one-way roads due to the medians. Just cross when it's clear. It may take longer, but it's not more dangerous.
3. If there are no signals on the exiting approaches, that won't solve your proposed pedestrian problem. If there are (including flashing red), the roundabout will back up, which is a major problem.

[jeffandnicole]

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.
I like the idea of a 2 phase traffic light: one pedestrian phase where all cars are stopped, and then a cars phase where the intersection acts as a regular unsignalized intersection. For a roundabout you could even only have traffic lights at the entry points for cars, and just time the lights so that the roundabout would generally be expected to be empty by the time pedestrians get the green light. Alternatively, exiting cars could get a flashing red during the pedestrian phase.
I know that many US intersections use the unsignalized phase at night, where (I am assuming) you can activate the pedestrian phase by pressing the button, but are there any examples of intersections that solely use the traffic light as a pedestrian safety device without ever having protected phases for cars, and are there signalized roundabouts that aren't horrible traffic circles?

You're incorrect on your assumptions. Many states have been changing over and leaving the traffic lights operational at night. For the intersections that aren't, they are in flash mode all night. A pedestrian can't activate them by pushing the button.

Not sure what you mean by not having a protected phase for cars, but there are traffic lights used just for pedestrian crossings.

Part of the purpose of roundabouts is a cheaper alternative to traffic lights. If traffic lights are going to be used for pedestrian crossings, then don't even bother with the roundabout at that point and make it a regular intersection.

[yand]

1. It's harder to get into a roundabout if you begin stopped.
2. It shouldn't be hard to cross as a pedestrian, as you're effectively crossing a series of one-way roads due to the medians. Just cross when it's clear. It may take longer, but it's not more dangerous.
3. If there are no signals on the exiting approaches, that won't solve your proposed pedestrian problem. If there are (including flashing red), the roundabout will back up, which is a major problem.

I think 1 lane roundabouts are certainly safe to cross, multi lane roundabouts may be a bit trickier unless you add islands between the same direction lanes.
The point of a flashing red on the exits and solid red on the entrance is to allow the roundabout to empty at a slower rate while keeping pedestrians safe, so it won't necessarily back up. Then because after the pedestrian phase the light turns flashing yellow or green for everyone at the same time, it shouldn't be hard to get the roundabout into a free flowing condition again. The periodic interruptions would also allow slower trucks to enter busy roundabouts so they aren't waiting 10 minutes at a busy roundabout.

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.
I like the idea of a 2 phase traffic light: one pedestrian phase where all cars are stopped, and then a cars phase where the intersection acts as a regular unsignalized intersection. For a roundabout you could even only have traffic lights at the entry points for cars, and just time the lights so that the roundabout would generally be expected to be empty by the time pedestrians get the green light. Alternatively, exiting cars could get a flashing red during the pedestrian phase.
I know that many US intersections use the unsignalized phase at night, where (I am assuming) you can activate the pedestrian phase by pressing the button, but are there any examples of intersections that solely use the traffic light as a pedestrian safety device without ever having protected phases for cars, and are there signalized roundabouts that aren't horrible traffic circles?

You're incorrect on your assumptions. Many states have been changing over and leaving the traffic lights operational at night. For the intersections that aren't, they are in flash mode all night. A pedestrian can't activate them by pushing the button.

Not sure what you mean by not having a protected phase for cars, but there are traffic lights used just for pedestrian crossings.

Part of the purpose of roundabouts is a cheaper alternative to traffic lights. If traffic lights are going to be used for pedestrian crossings, then don't even bother with the roundabout at that point and make it a regular intersection.

Other benefits of roundabouts include safety and throughput, and the addition of pedestrian protection would allow them to maintain these benefits while improving the usability in areas where there are more pedestrians. There would still be savings with the addition of a traffic light to the roundabout since you don't need to install or maintain pressure plates etc. if the traffic light is button activated and flashing during car phase.
I think in general pedestrians should be able to turn traffic lights in flash mode to solid red by pushing the button. I am thinking of higher speed intersections with maybe not that much car traffic but you still want a better level of safety for pedestrians crossing it.

[SkyPesos]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

[yand]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

I feel like if you block an exit but not all the entrances, that would lead to the roundabout backing up. Although I do see how that could lead to needless waiting if the cars are entering and exiting on crossings where there are no waiting pedestrians. I suppose one way to solve this is to increase complexity with lane wise traffic lights. For example if a pedestrian is crossing on the right, then only allow cars in the left lane going straight/left to enter.

[Rothman]

As long as roundabout entrances are simple yield signs, pedestrian safety will always be an issue at busier roundabouts.  That said, putting up traffic lights or HAWKs (I hate HAWKs with a passion) would complicate the intersection.

I would think some form of RRFB would suffice.

[jeffandnicole]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

I feel like if you block an exit but not all the entrances, that would lead to the roundabout backing up. Although I do see how that could lead to needless waiting if the cars are entering and exiting on crossings where there are no waiting pedestrians. I suppose one way to solve this is to increase complexity with lane wise traffic lights. For example if a pedestrian is crossing on the right, then only allow cars in the left lane going straight/left to enter.

I don't think I've ever read a road improvement summary or story trying to resolve an issue that contained the words "to solve this is to increase complexity"...

[jakeroot]

2. It shouldn't be hard to cross as a pedestrian, as you're effectively crossing a series of one-way roads due to the medians. Just cross when it's clear. It may take longer, but it's not more dangerous.

This is true for single-lane roundabouts, but there is some inherent safety issues with larger multi-lane roundabouts when it comes to crossing as a pedestrian. Even if it's a series of one-way streets, you have to ensure that both lanes stop at each leg. With slip lanes (which are added far too often at roundabouts), that can sometimes mean crossing four, five, or even six different legs just to get to the far side (and just as many lanes, if not many more). Compare this to a large intersection, even with slip lanes, where the crossings are signalized (better for those with disabilities), and the slip lanes are almost never more than one lane (more than that are usually signalized).

[jakeroot]

As an examples to accompany my above post, even if it is an extreme example, let's look at this roundabout in Carmel, IN (E 116 St @ Hazel Dell Pkwy).

No signals. Cool for cars, sure. But for pedestrians, this is a nightmare. At a minimum, at least four lanes of traffic have to stop to let you go, and who knows how long that will take.

Crossing from one corner to the far corner? That may involve crossing as many as 11 lanes. Holy cow.


(image source: https://www.dronegenuity.com/projects/carmel-indiana-roundabout/)

[hotdogPi]

Crossing from one corner to the far corner? That may involve crossing as many as 11 lanes. Holy cow.

11 isn't much more than 8, which is what a typical intersection would require.

[jeffandnicole]

As an examples to accompany my above post, even if it is an extreme example, let's look at this roundabout in Carmel, IN (E 116 St @ Hazel Dell Pkwy).

No signals. Cool for cars, sure. But for pedestrians, this is a nightmare. At a minimum, at least four lanes of traffic have to stop to let you go, and who knows how long that will take.

Crossing from one corner to the far corner? That may involve crossing as many as 11 lanes. Holy cow.


(image source: https://www.dronegenuity.com/projects/carmel-indiana-roundabout/)

Actually, 13 lanes.  Crossing from the left towards the parking lot:  2 lanes, 2 lanes, 2 lanes, then from the parking lot to the right: 2 lanes, 2 lanes, 3 lanes.

[jakeroot]

Crossing from one corner to the far corner? That may involve crossing as many as 11 lanes. Holy cow.

11 isn't much more than 8, which is what a typical intersection would require.

Yes, but typical intersections have signals, with lights. Being able to stop traffic completely (plus all of the other ADA benefits, like crossing sounds or LPIs) is going to be an overall better experience for those on foot.

Someone in a wheelchair, using a walker or cane, or even being blind...they're going to have superior experiences at signalized crossings. Even with twice as many lanes, I would argue.

Regular intersections often have yielding turns across the crosswalk (improved with the LPI), but I would still rather have a couple lanes yielding to me while in a signalized crosswalk over hoping that as many as *13 lanes* (thanks jeffandnicole) stop for me.

[Revive 755]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

[yand]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

Pedestrian underpasses are the ideal solution, but many people in lower density regions perceive them as crime holes due to lack of sight lines and foot traffic.

A far enough crossing where drivers don't have to manage both navigating the roundabout and looking for pedestrians at the same time is also a safe solution, especially for crossing cyclists. If you make pedestrians go out of their way though, they may instead try to jaywalk.

The traffic light is an attempt to balance these factors.

[jeffandnicole]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

Pedestrian underpasses are the ideal solution, but many people in lower density regions perceive them as crime holes due to lack of sight lines and foot traffic.

A far enough crossing where drivers don't have to manage both navigating the roundabout and looking for pedestrians at the same time is also a safe solution, especially for crossing cyclists. If you make pedestrians go out of their way though, they may instead try to jaywalk.

The traffic light is an attempt to balance these factors.

It depends on a pedestrian's destination. If they are going straight across, walking down the road takes them out of their way.  But if they're turning left or right, the mid-block crossing actually can take less time.

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

[yand]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

Pedestrian underpasses are the ideal solution, but many people in lower density regions perceive them as crime holes due to lack of sight lines and foot traffic.

A far enough crossing where drivers don't have to manage both navigating the roundabout and looking for pedestrians at the same time is also a safe solution, especially for crossing cyclists. If you make pedestrians go out of their way though, they may instead try to jaywalk.

The traffic light is an attempt to balance these factors.

It depends on a pedestrian's destination. If they are going straight across, walking down the road takes them out of their way.  But if they're turning left or right, the mid-block crossing actually can take less time.

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

I assume roundabouts that currently have close intersection crossings are this way because the engineers/planners did their due diligence.

[kalvado]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

Pedestrian underpasses are the ideal solution, but many people in lower density regions perceive them as crime holes due to lack of sight lines and foot traffic.

A far enough crossing where drivers don't have to manage both navigating the roundabout and looking for pedestrians at the same time is also a safe solution, especially for crossing cyclists. If you make pedestrians go out of their way though, they may instead try to jaywalk.

The traffic light is an attempt to balance these factors.

It depends on a pedestrian's destination. If they are going straight across, walking down the road takes them out of their way.  But if they're turning left or right, the mid-block crossing actually can take less time.

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

I assume roundabouts that currently have close intersection crossings are this way because the engineers/planners did their due diligence.

From what I see nearby, it is more like designers read some newspaper articles about roundabout greatness and didn't give a second thought to anything else.

[jeffandnicole]

I've seen HAWK signals used at busier roundabouts to allow pedestrian crossings, but not sure if a full traffic signal setup for all sides is needed, as it would sort of defeat one of the selling points of a roundabout.

The roundabout at 14th Street and Superior Street in Lincoln, NE has signalized pedestrian crossings on two of the legs.  The other two legs are handled by pedestrian underpasses.

Pedestrian underpasses are the ideal solution, but many people in lower density regions perceive them as crime holes due to lack of sight lines and foot traffic.

A far enough crossing where drivers don't have to manage both navigating the roundabout and looking for pedestrians at the same time is also a safe solution, especially for crossing cyclists. If you make pedestrians go out of their way though, they may instead try to jaywalk.

The traffic light is an attempt to balance these factors.

It depends on a pedestrian's destination. If they are going straight across, walking down the road takes them out of their way.  But if they're turning left or right, the mid-block crossing actually can take less time.

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

I assume roundabouts that currently have close intersection crossings are this way because the engineers/planners did their due diligence.

From you, the OP.  Literally, the very first sentence you wrote:

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.

[yand]

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

I assume roundabouts that currently have close intersection crossings are this way because the engineers/planners did their due diligence.

From you, the OP.  Literally, the very first sentence you wrote:

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.

in terms of traffic analysis to determine which area has the highest demand for crossings. pedestrian safety is poor in this country in general, doesn't mean they didn't do due diligence in other aspects of planning.

[kalvado]

Much like deciding how many through lanes and turn lanes are needed, seeing where peds would be coming from and going to should require a lot more analysis than just sticking a crossing as close to a roundabout as possible. 

I assume roundabouts that currently have close intersection crossings are this way because the engineers/planners did their due diligence.

From you, the OP.  Literally, the very first sentence you wrote:

A criticism I've seen regarding roundabouts is that they are dangerous to pedestrians.

in terms of traffic analysis to determine which area has the highest demand for crossings. pedestrian safety is poor in this country in general, doesn't mean they didn't do due diligence in other aspects of planning.

There is a long thread on roundabout safety. Moral of the story - roundabouts are much less universal than people wanted to believe. It is pretty similar to the opiates problem - people act on one obscure research paper as if it is ten testaments, without really understanding what they are doing.

[Mr Kite]

It's fairly common in the UK to have signalised pedestrian crossings just before/after the roundabout like this...

Liverpool, England
https://maps.app.goo.gl/wAZyEWWN7hsphyKv8

[kalvado]

It's fairly common in the UK to have signalised pedestrian crossings just before/after the roundabout like this...

Liverpool, England
https://maps.app.goo.gl/wAZyEWWN7hsphyKv8

One thing to notice upfront: crosswalks are close to roundabout on 30 kph side street. Crosswalk is significantly offset and signalized on a southern leg of A5058. There is room for about 6 cars between crosswalk and a circle
Compare that with
https://www.google.com/maps/@42.6888409,-73.8313851,3a,75y,40.75h,69.34t/data=!3m6!1e1!3m4!1ssUiaokswDJaDdffYVsVvYA!2e0!7i13312!8i6656
There is less than 1 car length available for exiting traffic. Pushbutton activated flashers do help, though; I believe they were added a year after construction (talking about due diligence).
Also, A5058 has a 40 km/h speed limit - and as far as I understand UK practices it is obeyed; Fuller rd (155) is 30 MPH=48 kph posted, and actual traffic is 40 MPH=65 km/h on a slow day. 

[Mr Kite]

A5058 is 40mph. People routinely do over 50.

[cjw2001]

As an examples to accompany my above post, even if it is an extreme example, let's look at this roundabout in Carmel, IN (E 116 St @ Hazel Dell Pkwy).

No signals. Cool for cars, sure. But for pedestrians, this is a nightmare. At a minimum, at least four lanes of traffic have to stop to let you go, and who knows how long that will take.

Crossing from one corner to the far corner? That may involve crossing as many as 11 lanes. Holy cow.


(image source: https://www.dronegenuity.com/projects/carmel-indiana-roundabout/)

For almost all of the crossings you would be only doing a 2 lane cross at one time (with the exception of the one southbound leg with a third lane.  There are pedestrian refuge islands between the groups of lanes.   That said this area has very little pedestrian traffic.   If there were more pedestrian traffic Carmel would likely add RRFB flashing beacon lights like they've done at many other roundabouts in the area.