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Old 05-11-2014, 12:10 PM
 
410 posts, read 391,168 times
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Quote:
Originally Posted by jade408 View Post
I work on a street like this. The lights are poorly timed. I can barely make it across the street before the light changes, and it is 3 minutes for the full cycle. I have been on worse streets where the full pedestrian cycle takes five minutes. Go ahead and set a timer for 5 minutes, and imagine waiting that long to cross the street.
Here are two things pedestrians would likely want when crossing at a traffic signal:
  • The Flashing Donít Walk is long enough to safely cross the street.
  • Minimized delay before the Walk comes up (IE. Short cycle lengths).
Pedestrian advocacy groups have argued that people donít have enough time to safely cross the street. The problem is by giving pedestrians more time to cross the street, the cycle length of the traffic signal will often need to run longer, leading to increased pedestrian delay. Studies have found that when pedestrians are required to wait a long time for a pedestrian interval, many will simply ignore the signal and cross during a gap in traffic. This fact may negate any potential safety benefits achieved by providing increased crossing times to pedestrians.
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Old 05-12-2014, 04:16 PM
 
Location: Valdosta (Atlanta Native)
3,535 posts, read 3,087,800 times
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Quote:
Originally Posted by augiedogie View Post
Demonta: This is much the way the streets look here in Lubbock, which is great. What they've left out in some cases, however, is the connections so that you don't so often get on the main streets to get to another street less than a block away.
Well, the paths are ment for pedestrians, not cars. You can walk or bike between neighborhoods without having to go to the main rd. Anyway, its much better walking between them than wasting gas driving less than a mile.
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Old 05-12-2014, 04:37 PM
 
Location: Oakland, CA
27,171 posts, read 29,768,960 times
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Quote:
Originally Posted by impala096 View Post
Here are two things pedestrians would likely want when crossing at a traffic signal:
  • The Flashing Donít Walk is long enough to safely cross the street.
  • Minimized delay before the Walk comes up (IE. Short cycle lengths).
Pedestrian advocacy groups have argued that people donít have enough time to safely cross the street. The problem is by giving pedestrians more time to cross the street, the cycle length of the traffic signal will often need to run longer, leading to increased pedestrian delay. Studies have found that when pedestrians are required to wait a long time for a pedestrian interval, many will simply ignore the signal and cross during a gap in traffic. This fact may negate any potential safety benefits achieved by providing increased crossing times to pedestrians.
That is why there is traffic calming and road diets. If the goal of the street is to move cars as fast as possible, it is difficult to make it safe for pedestrians.

You need to make other road changes to make things safer. Like adding a median for long crossings. Changing the signal timing, so turns do not conflict with pedestrians, and lowering the speed limit.
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Old 05-12-2014, 06:14 PM
 
2,388 posts, read 2,963,874 times
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Quote:
Originally Posted by impala096 View Post
^The lights in downtown Portland are timed at 12.5 mph which provides great progression for drivers. Portland’s grid spacing is much smaller than South Philly (~80m vs. ~140m) so the lights have to be timed for a slower speed to maintain good grid-progression.

Portland's current grid (timed for 12.5 MPH) - YouTube

Any street with consistently spaced traffic signals can theoretically achieve perfect progression (by adjusting the speed limit and cycle lengths of the corridor). Of course my comments in this thread have focused on two-way high speed arterials which is a completely different animal than a downtown grid.


All the arterials around here are 60-70 km/h (37-43mph) but they're all divided with the occasional cut out for center lane turning. The lights are only every 400-1000m so as long as you check your speed and it's not rush hour it's easy to ride a green wave if you're driving.

This of course comes at the expense of pedestrians. When I walk to the shops I have to cross the collector street I live off of then I have to cross the major arterial. If I get to the intersection just as the arterial is getting the green it can take me up to 3.5 minutes to cross both sides.

New Jersey infamously accomplishes near freeway speeds and near freeway volumes with this set up - eff the peds!
https://www.google.com.au/maps/@40.2...07TMNj90MA!2e0
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Old 05-13-2014, 12:16 PM
 
410 posts, read 391,168 times
Reputation: 500
Compare these two high speed arterial intersections. Would you rather walk one really long crosswalk or two short ones? FYI, both intersections are 6 lane high speed arterials.

Typical intersection, direct left turns...


Innovative intersection, no direct left turns....
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Old 05-13-2014, 02:00 PM
 
3,950 posts, read 4,064,390 times
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Look at number 2, not the street itself but everything you would be walking to on those fancy streets, and imagine this as the commentary:

The Diverging*Diamond - Strong Towns Blog - Strong Towns

Watch the video. It's brutal.
#2's not an exact match for the video, but it's surprisingly close. It's surprising how many roads are.
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Old 05-14-2014, 12:47 AM
 
Location: New York
80 posts, read 169,747 times
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Quote:
Originally Posted by augiedogie View Post
Demonta: This is much the way the streets look here in Lubbock, which is great. What they've left out in some cases, however, is the connections so that you don't so often get on the main streets to get to another street less than a block away.
It has to do with population, privacy and corridors.
You need corridors in axis to have equal paths to many destinations. This encourages pedestrian to walk or ride bikes to get from point A to point B.
Moreover, some corridors and streets were made before the housing boom, aka there are many more houses now and what used to be one house is now a whole private neighborhood.

Look at the examples in Oslo and Lille.
Look at the redevelopment of Lille where the main destination were the warehouses for work but even after expanding and connecting streets, they had to re-redevelop downtown where transportation hubs became the highlight.
Here in the US, it's a little different. More houses are now being built and our roads are becoming useless as they were not intended to be used with a heavy population in mind.
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Old 05-14-2014, 12:53 AM
 
Location: New York
80 posts, read 169,747 times
Reputation: 59
Quote:
Originally Posted by impala096 View Post
Compare these two high speed arterial intersections. Would you rather walk one really long crosswalk or two short ones? FYI, both intersections are 6 lane high speed arterials.

Typical intersection, direct left turns...


Innovative intersection, no direct left turns....
There is a misconception between overall pedestrian corridors and crosswalks.
At a crosswalk, there is always a risk of someone getting ran over even if the intersection is slimmer to cross.
That's why pedestrian bridges are built. But when one isn't available, small crosswalks are preferred as opposed to long ones. In essence, your conclusion is correct. But it creates a more overall traffic for automobiles
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Old 05-14-2014, 08:46 AM
 
410 posts, read 391,168 times
Reputation: 500
One issue with the 2nd picture is that pedestrians have no destination to go to when they are in the "median". Here's a poor example of what I'm envisioning, but if the medians were larger you could achieve commercial developments.

https://www.google.com/maps/@40.6895.../data=!3m1!1e3

^This example is not pedestrian friendly at all, as i cannot find a single crosswalk that provides access to this roughly two-mile long couplet. However, there are some potentially big benefits with a similar type of design (IE. shorter crosswalks for pedestrians & no conflicting left turns for vehicles). Why aren't more major arterials designed with medians wide enough for commercial development?

Here's a similar example. The intersection widens out at the intersection before narrowing back down.

https://www.google.com/maps/@33.0983.../data=!3m1!1e3
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Old 05-14-2014, 03:11 PM
 
Location: New York
80 posts, read 169,747 times
Reputation: 59
Quote:
Originally Posted by impala096 View Post
One issue with the 2nd picture is that pedestrians have no destination to go to when they are in the "median". Here's a poor example of what I'm envisioning, but if the medians were larger you could achieve commercial developments.

https://www.google.com/maps/@40.6895.../data=!3m1!1e3

^This example is not pedestrian friendly at all, as i cannot find a single crosswalk that provides access to this roughly two-mile long couplet. However, there are some potentially big benefits with a similar type of design (IE. shorter crosswalks for pedestrians & no conflicting left turns for vehicles). Why aren't more major arterials designed with medians wide enough for commercial development?

Here's a similar example. The intersection widens out at the intersection before narrowing back down.

https://www.google.com/maps/@33.0983.../data=!3m1!1e3
Do you want a clear example as to what NOT to do but let's do it anyway even though it's an important hub?\
East New York Station in Brooklyn.
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