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Old 03-26-2015, 06:17 AM
 
Location: Youngstown, Oh.
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Quote:
Originally Posted by impala096 View Post
Traffic signals along a one-way street can be timed for steady progression. This progression, known as the “green wave”, can be extremely effective at limiting the speed of traffic. By converting a one-way street to a two-way street, you lose this ability to regulate the speed of traffic as two-way streets are much more difficult to coordinate.

The signals along 1st Avenue are currently timed for 27.5 mph. An aggressive driver is incapable of outrunning the 27.5 mph “green wave”. If 1st Avenue was converted to a two-way street, aggressive drivers may decide to drive 65 mph.

1st Avenue in Manhattan (cruising at 27.5 mph):

West Side Street in Manhattan (cruising at 65 mph):
between 9:57 to 10:57 in the video, the driver travels 5,800 feet and averages 65 mph. The posted speed of West Side Street is 35 mph.
Maybe it's apples and oranges, but I know of 2 one-way streets here that have timed signals, and they are timed for 35mph. But, I've heard people joke that if they're timed for 35mph, they are also timed for 70mph.(as a non-driver, I don't know if this is true, or not) I haven't watched either video, yet. If the joke is true, are there other factors that would prevent someone in the first video from going 55?
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Old 03-26-2015, 07:27 AM
 
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Quote:
Originally Posted by JR_C View Post
Maybe it's apples and oranges, but I know of 2 one-way streets here that have timed signals, and they are timed for 35mph. But, I've heard people joke that if they're timed for 35mph, they are also timed for 70mph (as a non-driver, I don't know if this is true, or not) I haven't watched either video, yet. If the joke is true, are there other factors that would prevent someone in the first video from going 55?
A driver doing 70 mph on that one-way street is just speeding up to the next red light. There isn't much truth to the joke but there is a caveat. A driver who is at the end of the "green wave" on a one-way street can exceed the speed limit until they catch up to the start of the wave. To limit this, short cycle lengths should be selected. Short cycle lengths are also beneficial to pedestrians as it reduces the delay waiting to cross the street. One-way streets are naturally conducive to shorter cycle lengths compared to two-way streets since they don't require inefficient left turn phases that are commonly seen along two-way streets (the more required phases, the higher the required cycle length).

OTOH, a driver on a two-way street does benefit from going 70 mph, since the faster they go the more green lights they make it through. The time-distance diagrams below helps visualize the progression along one-way and two-way streets. Hopefully these time-distance diagrams are intuitive to follow.

One-way street progression:


Two-way street progression:
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Old 03-26-2015, 07:53 AM
nei nei won $500 in our forum's Most Engaging Poster Contest - Thirteenth Edition (Jan-Feb 2015). 

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Location: Long Island / NYC
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what does each row represent?
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Old 03-26-2015, 08:24 AM
 
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Quote:
Originally Posted by nei View Post
what does each row represent?
Each row (red/green lines) represents traffic signals spaced a certain distance apart. The diagonal red and blue lines represent vehicle trajectories when traveling at a certain speed. Here's a link that talks about time-distance diagrams in more detail:

Traffic Signal Timing Manual: Chapter 6 - Office of Operations
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Old 03-26-2015, 09:23 AM
 
Location: The City
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Quote:
Originally Posted by nei View Post
what does each row represent?
makes me dizzy
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Old 03-27-2015, 08:01 AM
 
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As a pedestrian do you want to encounter the Tortoise or the Hare? The Tortoise ends up with a higher average speed in the race.



The cannonball run driver doesn’t even average the posted speed limit of 35 mph between I-478 and 57th Street (7:22 to 16:00 in the video). Sure, the driver is cruising at 65 mph between red lights, but when the red light delays are taken into account the average speed is only 32 mph. If the street was converted to one-way with the lights timed for 35 mph, the average speed would increase by 3 mph (from 32 mph to 35 mph).

The cannonball run driver would benefit from West Side Highway being one-way since the average speed (from I-478 to 57th Street) would increase from 32 mph to 35 mph. Pedestrians would benefit with it being one-way because the cannonball driver would be traveling at 35 mph instead of 65 mph. I’m trying to make a point and am not suggesting West Side Highway should actually be converted to a one-way street.
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Old 03-30-2015, 08:55 AM
 
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A story in the Boston Globe talking about making the one-way streets permanent. The majority of local residents want to keep the one-way streets.

Quote:
Caught in Southie... a popular neighborhood website... conducted an unscientific online poll and found that among the 360 respondents, two out of three wanted to keep the one-way streets. In another online survey, by the website Southie Streets, 63 percent favored making the one-ways permanent.
Even with snow gone, one-streets popular in South Boston - Metro - The Boston Globe

Last edited by impala096; 03-30-2015 at 09:17 AM..
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Old 03-30-2015, 10:41 AM
 
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Hamilton Street in Vancouver Canada has head-out angled parking on one side of the street and parallel parking on the other side. This street has the same curb-to-curb distance (roughly 33 feet) as a typical South Boston street. This is what South Boston might look like with one-way streets.

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Old 03-31-2015, 09:27 AM
 
410 posts, read 389,294 times
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The temporary one-way streets wasn't limited to South Boston...

Quincy converted 15 to 20 streets to one-way....
Quincy's temporary one-way streets have drivers confused - News - Wicked Local - Boston, MA

East Cambridge converted several two-way streets to one-way...
Some East Cambridge streets to become temporary 1-ways - 7News Boston WHDH-TV

Salem Police Make 20 Streets Temporarily one-way...
Salem Police Make 20 Streets Temporarily One-Way | Salem, MA Patch

Hull converted 29 streets to one-way...
Temporary one way streets in Hull will end on Monday - News - The Patriot Ledger, Quincy, MA - Quincy, MA

Chelsea To Temporarily Convert Several Streets to One Way...
City of Chelsea To Temporarily Convert Several Streets to One Way
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Old 04-01-2015, 07:49 AM
 
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The one-way streets in South Boston have been extended through June 1 while city officials hold community meetings to determine if the one-way streets should become permanent.

Quote:
“We’ve received a tremendous amount of positive feedback from South Boston residents about how the emergency reconfiguration has relieved traffic congestion and increased public safety,” Walsh said. “I look forward to engaging in a robust discussion with the community on the future of these neighborhood streets.”
one-way streets extended to June 1, may become permanent - Metro - The Boston Globe
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