Who says LRT or streetcars can’t operate at close headways!
There is a reoccurring theme from the SkyTrain trolls at TransLink and the city of Vancouver that LRT can’t operate at close headway’s and one can hear the wailing and gnashing of teeth when they are corrected. “Lies”, they scream in unison, at every correction. It is extremely funny and extremely sad at the same time that the SkyTrain trolls firmly believe their fairytales to be true and those who support modern LRT are some sort of latter day Luddite.
How many SkyTrain systems have been built Daryl? Only seven you say. Pity.
So here we have a contemporary photo from San Fransisco with a tram, a bus and a tram traveling at 3 second headway’s. Hmmm, say it ain’t so!
You are still out there telling lies. It can never be 3 seconds because they are too slow. It takes forever even to move a few feet. The street is jammed. Can’t you see? And the whole lane is gone. Skytrain doesn’t take any lane and travel way faster and smoother.
Zwei replies: I am only posting this to show what a SkyTrain Troll does, constantly naysay LRT/trams without any care for the truth. Streets are jammed, not likely.
Headway’s are the distance or time between each train on a given route, based on the safe braking distance of the vehicle. On Broadway, I have seen 3 B-Line buses traveling a 3 second headway’s, traveling at about 50 kph. Pictures don’t lie, but SkyTrain Trolls do.
I don’t believe you are really that ignorant. How long have you been interested in transit? I have been on the F-line. I have seen that exact thing. It is called bunching….and it is very bad. I show up on Market and go to cross the street. I see 4 streetcars in a row pass while I am waiting. I cross, no streetcar for 15minutes. Market Street is a busy street with lots of lights. Just because 4 streetcars go past in 4 minutes does not mean there is a 1 minute headway, or that 1 minute headways are possible on a given route. To summarize you can have very short headways at low speeds on a segment that has no traffic conflicts (Karlseruhe), the more traffic/pedestrian conflicts you have the more accommodation you need to make for that traffic, either with grade separation or with increased headways. That is why you can’t have both high speeds and short headways on Broadway without significant grade separation. Just try and imagine using Granville if signal priority for LRT on Broadway changed the light every 2 minutes…out of sequence with the regular light schedule…..If you want signal priority on Broadway the headways will be limited to somewhere around 5minutes. If you don’t have signal priority…..why bother…..
Zwei replies; naysay, naysay, naysay and where do you get headway’s of 5 minutes with signal priority, if you actually knew what you are talking about, which you don’t (SFU grad maybe?), it is the tram that operates the signals, giving the tram priority. Also, a modern tram would have the capacity of all three vehicles, thus with modern trams, there are far less vehicles on the road.
You have to understand with LRT, the nature of Broadway will change, it will be transformed from a car oriented arterial road to a high capacity transit corridor, allowing cars for local businesses and residents. Traffic will be reduced so the signalling will be changed to conform with less traffic.
I always find it interesting that local planners say; “it can’t be done”, while real transit experts say it can.”
The failure of our regional transit planning can be pinpointed by the failure of our universities to actually create a faculty of urban transport because you and the rest of the planners in Metro Vancouver are 50 years out of date and completely out of touch with modern public transport philosophy.
Oh by the way Rico, I am not the ignorant one, I have forgotten more about transit than what you know. 30 years of corresponding with real transit experts and engineers and a firm background in railway and transit history and a constant communication with experts today, put me on the cutting edge of transit philosophy, unlike the dull “saws” we have trying to plan for subways, because they are cool, without any concern for cost and operation.
Maybe I was unclear or maybe you just did not understand. The issue with short headways with strong signal priority will not be on Broadway. The issue will be with North/South traffic that must cross the Broadway corridor. Streets like Main, Cambie, Oak, Granville, Burrard and Arbutus. You can not put 2minute signal priority (which can’t by synchronized with the regular light cycle) on Broadway without totally screwing up North/South traffic. Not very complicated.
Your 30 years of experience does not help much if you never listen and never learn. Like headways…….you should be able to understand the concept by now…….
Zwei replies: Rico, your insults, compounded by your ignorance and arrogance is common among the Skytrain trolls. With priority signalling, the tram controlls the lights and simple red (stop) green (go) works well. With long trams with a capacity of 300 or more people, I see a maximum of 2 minute headway’s, which give ample capacity for present and future use. I find it hypocritical that everyone wants to reduce car use and when LRT and passive traffic calming come into the for, the very same people scream to high heaven.
I have emailed a signalling engineer in Europe who has been very helpful in the past and he said depending on the traffic flows a preemptive signal maybe a short as 10 seconds in the red phase stopping cross traffic.
Hi Zwei,
I think you are still looking at it from a Broadway perspective instead of the larger North/South traffic flow. Assuming a 10 second red phase is feasible in the Broadway situation means about a 30 second cycle before full traffic flow resumes. If the headways are 2 minutes that is a 25% decrease in North/South traffic flow (the regular lights still need to cycle). Also remember Streets like Main, Granville, Burrard and Arbutus are significant transit routes as well. Now take 25% of the flow away from those streets…….
Zwei replies……………….so you think regular traffic should have priority over transit? Why are you not lighting your hair on fire over bike lanes or the loss of traffic lanes on the Burrard Bridge, but golly gee whiz, if a tram dares to stop traffic, the world comes to an end.
Well said Zwei!
Rico uses sophistry to make a point that is not actually valid. His latest point is a case in point. The idea of a 25% reduction of flow from cross streets is completely wrong, and displays a lack of understanding how signal priority works.
To put it in simple terms: 1) if the light on Broadway is already green when the tram passes, cross-traffic is totally unaffected. 2) If the light is green when the tram begins to approach, and is about to change, the tram’s signal priority will tell it not to change – for a few more seconds. Immediately after the tram passes, the light will change, and stay green for cross-traffic the usual length of time, or possibly even slightly longer if warranted, to deal with the added traffic. 3) If the light is red on Broadway before the tram approaches, it will change to green as the tram approaches. In this case, the light would have already been red for some time (it would not have changed to red as the tram was nearing), and a switch to green would have only a small negative impact on cross-traffic.
The traffic light system of a signal priority intersection is naturally designed to minimize quick light changes. It is well-known in the literature that pure signal priority on busy traffic routes has a very small effect on cross-traffic.
@ John, well said:
“noun
(plural) -ries 1. a.a method of argument that is seemingly plausible though actually invalid and misleading
b.the art of using such arguments
2.subtle but unsound or fallacious reasoning
3.an instance of this; sophism”
Maybe “reek” just has down syndrome, instead. His ramblings don’t seem very coherent to me.
If the COV built some underpasses for major cross streets and let cars pass under the tram on Broadway, the delay would be zero. I’ve had my fill of the COV “engineers” who are a disgrace to the profession and aren’t anything more than over paid glorified monkeys.
At the COV, the crap has risen to the top in the engineering department. Engineers at the COV didn’t do any noise mapping or dispersion modeling before implementing the 99 service on Broadway. I’m working on an industrial project in Metro Vancouver where the sound level can’t exceed 55 dBA at the property line, including the background noise, or 40 dBA at any residence. Along Broadway, the noise is about 85 dBA at the property line or curb and is well over 70dBA inside residences (you can’t hear someone talking to you when the 99 screams past).
“Engineers” at the COV haven’t been fired for this and have even received promotions for their “sustainable transit”. When noise complaints about transit just go to the screwed ups who are responsible at the COV, you can keep it completely under wraps, it seems. Outstanding.
http://www.engineeringtoolbox.com/decibel-d_59.html
Keep in mind guys, even the best intersection signal manipulation systems, Green Light Phase sustainers and Red Light Phase shorting systems (inside joke, I will tell you later) only promise that, at any given time any transit vehicle (bus or surface rail vehicle) will get a red light 1 out of 4 times in the direction favored for transit. This is assuming that, signaled intersections are no fewer than 300-350 metres apart and (in this case) provincial or state traffic laws allow such signal manipulation as well as the signal intersection is not already set to some kind of minimum legal value in one part of the various signal phases.
What can be most frustrating is if the intersections are less than 300 metres apart the chances of a transit vehicle getting stopped by a red light increases. Increasing the frequency of the service or decreasing the dwell time between the transit vehicles also lowers the effectiveness of these systems as well. There are some newer systems that can overcome some of the difficulties but, the complexity of the newer signal manipulation systems as well as the costs goes up the more complex a traffic environment gets.
Ottawa faced this problem on the downtown portion of the Transitway. The 2 parallel downtown streets Albert (westbound direction) and Slater (eastbound direction) Streets that move 185-200 buses per direction per hour during the peak periods have their traffic signals favor the buses traveling in the east-west direction. At Bank Street (the North-South Street stratling both Albert & Slater) there is no signal manipulation system being used, just the traffic computer allowing 37 second green lights in a 1 minute total cycle (+/- 2-3 seconds for overages). The North-South direction some of them like Bank St. major streets in their own right, get approximately 14 seconds of green lights that, gives 9 seconds for yellow signal phases in both directions as well as the combined all red signal phase. It was thought that a signal manipulation system would work along here. When the major system manufacturers were consulted about the operations here they all shrieked! This corridor has (The downtown portion of the Transitway) has 14 signaled intersections in a distance slightly less than 2.5 km, 8 signaled intersections in just the 1.3 km between Bronson Ave.to Elgin Street portion (Centretown CBD). That’s a signaled intersection every 162.5-178.6 metres on a average basis through the central portion of the city’s core. The North-South Streets crossing this corridor represent no fewer than 4 major area wide north-south traffic arteries as well as 3 of the 4 centrally located inter-provincial bridges to Quebec. Well the system designers told Ottawa it was definitely possible but it would be complex and costly and may force the moving of some of the downtown Transitway stations to maximize the effect the system. If you have never seen the bus tops on the central part of the Transitway, they represent much work, widened sidewalks and specially designed curb side bus bays and upgraded high capacity bus shelters, not easy thing to pick up and move. After a legal search it was found that, under provincial law only 4 more seconds could be taken away from traffic signals in the north-south direction thus at best only 4 more seconds could legally added to the east-west transit favored traffic signals. So for all the large cost and at a minimum 1 year of potentially troubled implementation we would gain up to 4 seconds, the idea was dropped quickly and completely. Until the concept of the LRT tunnel came around it was believed that, unless massive changes to bus stop location and its associated service plus expensive new traffic signal systems were installed only flirting around the edges of the capability of the downtown Transitway could be done. In retrospect, this simple fact probably forced a great deal of LRT naysayers to come around to the concept of an expensive downtown LRT Tunnel.
I think in North America we jump to tunnels as a transit solution all too quickly and in Europe the Light Rail Renaissance all but did away with tunnels unless they were absolutely necessary.
In the USA subway and major tunneling are approved because it is a way to spend massive amounts of federal dollars, “greasing” the various wheels around the transit project. Simply put, having rapid transit in a subway in the USA is more of a political thing, than a transit thing. The same is true of SkyTrain, where huge amounts of monies are spent with friends of the government, engineers, architects, cement manufacturers , etc. (about 4 to 5 times more than with LRT) by building with light-metro.
One thing I have believe is that we must change the 1930’s road rules and update them for modern LRT a we are building 21st century transit on roads that have legal rules dating back to the 19th century. They did it in the UK and I believe we must do it here too.