Transportation

York Blvd Scramble Intersection 'Inefficient': Traffic Office

By Ryan McGreal
Published February 20, 2009

this blog entry has been updated

RTH reported earlier this week that the proposed pedestrian scramble intersection was removed from the York Boulevard Streetscape Master Plan, as the result of a traffic study conducted in January by the Public Works Department's Traffic Engineering and Operations office.

I contacted Hart Solomon, the traffic engineer in charge of the study, for more information. He explained that the study, which modeled traffic flows based on standard traffic signal timing calculations, found that the lane reductions combined with the scramble would back traffic up as far as Queen Street after an hour of peak use.

He explained:

The reason the scramble is so inefficient is that all vehicular traffic remains motionless when the pedestrians cross in the scramble operation, and time has to be provided for pedestrians to cross the road diagonally, so that means a fairly long time without any vehicles moving. In the normal operation, vehicles are always moving in one or the other direction (except for the amber light, of course), so time is used much more efficiently.

I replied to ask him whether the model assumes or calculates that total traffic volume will remain the same - after all, demand for lane capacity is flexible and some people will choose alternate routes or different times to avoid congestion - but did not receive a subsequent response in time for this article. Update: Read Hart's response in a subsequent blog entry.

Solomon also argued that the pedestrian scramble is "not particularly friendly to pedestrians."

A scramble intersection works on a three-stage cycle: vehicular traffic flows one one directional axis (e.g. east-west), and then on the other directional axis (e.g. north-south), and then all traffic stops and pedestrians can cross in any direction.

During the first two stages, vehicles have the right of way and pedestrians are not allowed to cross. As Solomon pointed out:

This means that if a pedestrian arrives at the wrong time, he or she can be standing still with nowhere to cross for quite a while. At a normal signal, one always has the option of crossing in one or the other direction.

Councillor Bob Bratina (Ward 2, downtown) has announced that he will attempt to have the scramble intersection re-included in the final York Blvd Plan before it goes to Council for approval.


Update: Hart Solomon replied to my query on Monday. You can read his response in a subsequent blog entry.

Ryan McGreal, the editor of Raise the Hammer, lives in Hamilton with his family and works as a programmer, writer and consultant. Ryan volunteers with Hamilton Light Rail, a citizen group dedicated to bringing light rail transit to Hamilton. Ryan writes a city affairs column in Hamilton Magazine, and several of his articles have been published in the Hamilton Spectator. He also maintains a personal website and has been known to post passing thoughts on Twitter @RyanMcGreal. Recently, he took the plunge and finally joined Facebook.

19 Comments

View Comments: Nested | Flat

Read Comments

[ - ]

By Capitalist (anonymous) | Posted February 20, 2009 at 12:32:26

Downtown Hamilton doesn't have the pedestrian volumes to warrent a scramble intersection. What are we going to do, let cars idle (and pollute) waiting for all the people in downtown Hamilton to cross the road diagonally with their pathetic scooters?

Permalink | Context

[ - ]

By jason (registered) | Posted February 20, 2009 at 12:38:36

Comments like the one above make a good case for a moderated forum. God forbid you ever have an accident or brain injury and need a "pathetic" scooter. That's disgusting.

I'm sorry, but this line from Solomon is too much: "traffic would back up as far as Queen Street". I mean, seriously. York is a wide-open freeway with zero congestion. I can't feel that our intelligence has been insulted with that response.
Maybe they should rename the Downtown Secondary Plan, "Putting People 2nd or 3rd".

Permalink | Context

[ - ]

By Capitalist (anonymous) | Posted February 20, 2009 at 12:47:24


Jason,

by "moderated" you mean censure any views that are not similar to your own. This is the road that the left is now taking when they are on the losing side of an argument. Look at university campuses.

Permalink | Context

[ - ]

By Jonathan (registered) | Posted February 20, 2009 at 13:08:48

This is pointless in this location anyway. People would only use it to get from the parking garage to the market. King/James and King/John should be scramble intersections. That would fit in nicely with the upcoming Gore Park project.

Permalink | Context

[ - ]

By Frank (registered) | Posted February 20, 2009 at 13:23:59

Comments from people who have obviously not looked at the project plans are useless. Once the redevelopment is complete, there would be a guaranteed increase in pedestrian traffic. And no Capitalist, it's not that you're opinion differs, it's that your comment is derogatory.

I say give it a shot, try one there and one near Gore and see how they work. I'm sick of them using "models" as an excuse for not developing the downtown in a way that moves it forwards rather than back into the 60s.

Permalink | Context

[ - ]

By adrian (registered) | Posted February 20, 2009 at 13:25:24

I like the way they do it in Rome - pedestrians always have the right of way (at least in certain intersections). Want to stop traffic? Step out into the street. It's a pedestrian scramble all of the time, with no need for signals.

Of course, on our urban freeways, it'd probably be a recipe for suicide.

Permalink | Context

[ - ]

By kevlahan (registered) | Posted February 20, 2009 at 13:41:34

I can answer Ryan's question: the model the City of Hamilton uses for traffic calculation (called ME2) would assume a fixed volume of traffic. It would not take into a account changes in traffic levels due to changes in congestion, signal timing, number of lanes etc. Traffic volumes would be inputted based on current measurements.

To account for changes in total traffic levels (e.g. motorists choosing alternate routes, travelling at different times or switching to other modes) would require either an agent-based system (which models transportation decisions by individual agents), or a manual reduction of traffic flow based on the expert knowledge of the user.

One other limitation of these systems is that they don't include cyclists or pedestrians as part of the traffic model.

Eric Miller's UTRAC group at the UofT is working on a fine grain agent-based system called TASHA (travel activity for household agents) that could actually predict changes in behaviour (like avoiding a particular street because of its higher traffic volumes, or switching to public transit), but it is still in the 'research' stage.

The bottom line: the traffic models currently used by Hamilton (and all other cities) are good at optimizing traffic flow given a fixed layout (e.g. by changing traffic light timing, adding turn lines), but they can't predict what will happen if the layout changes significantly (one-way to two-way conversion, lane removal, population growth).

Permalink | Context

[ - ]

By ...In Time (anonymous) | Posted February 20, 2009 at 13:52:31

I say add it to King & James first, re-do the York Blvd without the scramble yet. Then if the Scramble at K&J is a hit with Pedestrians & Drivers, and the pedestrian numbers increase in the 'Market District', then go ahead and add it here. I don't think it's needed at the Market just yet.

Permalink | Context

[ - ]

By Ryan (registered) - website | Posted February 20, 2009 at 14:42:06

kevlahan wrote:

I can answer Ryan's question: the model the City of Hamilton uses for traffic calculation (called ME2) would assume a fixed volume of traffic. It would not take into a account changes in traffic levels due to changes in congestion, signal timing, number of lanes etc. Traffic volumes would be inputted based on current measurements.

If that's true, the study is absolutely useless as a predictive tool and should not be a consideration in whether to implement the scramble.

Permalink | Context

[ - ]

By A Robot (anonymous) | Posted February 21, 2009 at 01:39:19

Why when you can easily jaywalk the ramp between the market and city centre/hall. K&J makes sense because it would get rid of the current james southbound right turn mayhem with its three second green light.

Permalink | Context

[ - ]

By seancb (registered) - website | Posted February 21, 2009 at 02:08:28

I agree that a scramble would be well suited to king/james... but "mayhem"? Come on...

Permalink | Context

[ - ]

By jason (registered) | Posted February 21, 2009 at 09:14:18

Lol...this is too funny and too typical of Hamilton. Other cities look for ways to slow urban traffic and make life more attractive for cyclists, pedestrians etc..... here, we keep looking for ways to keep the cars bombing along. I haven't heard anything regarding removing transport trucks off York during this process. So, those market stalls that can be set up on the York sidewalk right next to live traffic lanes will have transport trucks flying by still??? This actually could be a recipe for "mayhem". But at least it's "efficient".

Permalink | Context

[ - ]

By g. (anonymous) | Posted February 22, 2009 at 01:09:48

the odd thing about this is that there really isn't that much vehicular traffic related to this intersection heading north/south. if you look at a map and think about it, very few cars or trucks emerge from the jackson square or city centre ramp, ie. north bound. very few cars or trucks head south bound on mcnab, because you are either heading into the loading docks if you continue straight or you are turning left onto york, but why would you unless you are coming out of a parking lot and there are equally as accessible ways to go, vine being one of them. regardless there is no through traffic and the amount of through traffic should decrease along york after the two way conversion. it happened on james north.

this really is a very specific intersection in terms of pedestrian use because so many people use it to get to the library and market where it is most efficient to cross. it is not however,in any similar significant way specific for cars or trucks except those who need to enter the market loading area or the jackson square loading area. if this intersection was indeed turned into a scramble by say having the vehicles heading north or south wait twice as long or even three times as long, vehicular traffic that could would find another equally opportune way of reaching their goal.

slowing down the maybe 50 or so vehicles a day who must use this intersection is immeasurably more economical than slowing down the hundreds or thousands of people using the intersection each day. i'm thinking specifically of the pedestrian zoo the intersection is on a saturday when there is almost no north south vehicle traffic during market or library hours.

keep in mind as well that i am one of those people driving into the loading docks, and i would rather wait an extra 20 or 30 seconds in exchange for a more friendly pedestrian crossing. i have never had to wait, in 17 years of using that intersection more than one light cycle. in fact i can't think the last time i have waited at that light heading north or south with more than two other vehicles. compare this to many other intersections in the city where two or three light cycles are needed to make it through an intersection. this is not a hub of vehicular congestion that we need to be worrying about efficiencies.

i do think that it is remarkable that the city is making this stretch two way. i applaud the efforts of all involved and urge them to keep up the good work. it is the single most important thing the city can do to encourage the type of revival that is starting on james noth, converting all inner city one way streets, including cannon and main into two way streets.

traffic TO the city, not THROUGH the city!


Permalink | Context

[ - ]

By Urban Guy (anonymous) | Posted February 22, 2009 at 10:28:01

There is an interesting concept being tried out in London, England which originated in Holland. Because of copyright requirements I cannot quote by copying and pasting from the site here but if you go to: www.worldwidewords.org/turnsofphrase/tp-nak1.htm you will find an interesting article about the removal of ALL traffic control systems!! It's called "the naked street".
This site - it's called World Wide Words - is one of my favourite sites and I encourage you to sign up while you're there for the weekly newsletter which arrives every Saturday morning.
Anyway, what do you think of the "naked street" concept?

Permalink | Context

[ - ]

By LL (registered) - website | Posted February 22, 2009 at 12:45:59

I have a hunch that the "naked street" concept is somewhat culturally mediated. It's worth a try, but I don't know if it would work in North America right now. Maybe a small university town with a high proportion of divergent thinkers would be open to it - say, Eugene Oregon, Boulder Colorado, or even Guelph. Speaking of those types of towns, Davis California has had a lot of success with separated bike lanes. I think that's the way to go.

Permalink | Context

[ - ]

By kevin (registered) | Posted February 22, 2009 at 16:56:54

I was in New Zealand in 1989 and first experienced a scramble intersection in Auckland. I thought it was the coolest thing ever and couldn't imagine why we didn't use them in Canada. They also had decided to get rid of the penny. If the cash register said 42 cents, you rounded down, if it was 43, we rounded up.

Very very very simple little things to make life easier and nicer are too complicated for Canada, I despair.

Permalink | Context

[ - ]

By jason (registered) | Posted February 22, 2009 at 22:27:32

1989 eh? Well, hang in there. I'm sure we'll be doing some of those things here by 2074.

Permalink | Context

[ - ]

By TreyS (registered) | Posted February 23, 2009 at 12:56:51

The idea of a scramble intersection is great.

Except MacNab and York is silly. I was just stopped there at a red light, and the scramble idea occurred to me. It was Monday at 11:57 (noon), and the entire time not one pedestrian crossed, not one pedestrian was even in sight for the duration of the red light. And the Farmers' Market was open and it was lunch time for all the workers. where was everyone?

Put a scramble at King and James and that would make sense.

Permalink | Context

[ - ]

By jason (registered) | Posted February 24, 2009 at 09:26:36

this is an interesting point Trey. If the pedestrian activity doesn't warrant a scramble, I'd agree with you to not do it there. I'd hate for us to have our first scramble be a failure, making it harder to get them in the future.

I could see scrambles working great at King/James, King/John, James/Main etc....

Plus, I'd prefer our first scramble to be at an intersection with more amenities and destinations nearby, not a parking garage. Seems like this scramble idea is in keeping with Hamilton's priorities - get people from their cars into the market and back to their cars as quickly as possible.

Permalink | Context

View Comments: Nested | Flat

Post a Comment

You must be logged in to comment.

Events Calendar

Recent Articles

Article Archives

Blog Archives

Site Tools

Feeds