Comments

1. Haveacow says:

   June 18, 2013 at 2:43 pm

   The method used by the Americans is an attempt to calculate PRACTICAL capacity not theoretical capacity. Also there is a new school of thought on the issue about capacity. What is useful is to not get into a debate about how much capacity a line can can take theoretical or practical, (as a female transportation planner friend of mine so elequently puts it, “the mine is bigger than yours school of capacity” ) but, at what capacity do you start loosing a significant number of passengers because off overcrowding. Two friends of mine and I are developing our own mathematical model to predict this and plan to show it the APTA| next year.

   You have to be very careful about using the standard simple capacity calculation because it can significantly over and or undercount capacity, depending on the characteristics of the line in question. Simply said if you use a method that makes several assumptions about a line you may get an answer that is way off if those assumptions are wrong. For example, you have made several statements over the past months calculating the capacity of the Karlshrue system at the trunk point on Kaiser Strasse. After talking with the officials and touring their operation this past week I was slightly surprised that their actual practical capcity is about 25,000-28,000 p/h/d maximum. “The Yellow Wall” on kasier Strasse as the locals put it hide the fact that, many of those vehicles are only 1/3 to 1/2 full. The crowding slows down the LRV’s in the core so much that, (I am talking about kaiser Strasse before the tunnel construction project started) it is quite rare to have more than half of those vehicles full. One of the problems of scheduling when using the Karlshrue Model is that you made an assumption that the vehicle schedules are balanced when a great many of the S-Bahn lines operating into this city have unbalanced shcedules because of sharing rail space with so many other users. What this means is that, a line like the S6 which has 3 trains an hour at peak, makes a person assume that they are broken into 3, 20 minute intervals. This is not the case in fact it’s past schedule indicated that it left Bad Wildbad at 17, 47, and 57 minutes after the hour. When a schedule is this unbalanced ridership is greatly effected. One of the busiest S bahn lines in the area is not even operated by the local operator . The S3 that runs from Mannheim to Karlshrue is operated by RheinNeckar S Bahn that centres the area around Mannheim. It runs 2 trains an hour at peak but, it uses full sized DB EMU’s that dwarf the capacity given by the dual powered LRV’s. This steals a considerable number of passengers away from the system but still adds traffic to the tracks going into the local Karlshrue Central Station, the Haupt-Bahnhof. Thus forcing many of the Karlshrue S-Bahn lines into unbalanced schedules.

   At work I have never used a capacity model that had any less than 20 variables in it. You need to use a method of calculation that takes in the carrying capacity of the stations and platforms. You should never use a method that assumes the maximum number of passengers on every train over an hour time period is equal to the “at the momment” crush capacity of said vehicles or in simpler terms, assumes that the Renovation Rate is 1.0. That is the average number of passengers over an hour divided by the actual number of passengers that traveled in that hour. The lower the the ratio the higher the turnover of passengers. Included you have to use a load factor modifier that attempts to gage really how full the vehicles really get. The actual measured maximum peak level of passengers in a car divided by the crush capacity. One often finds that, in North America that rarely gets above 0.85 or 85% of capacity.

   Lastly, when figuring out the standees it is very common to use the 4.0 passengers / metre sqd. many Canadian transit agencies never go beyond the range of 3.3-3.5 simply because at 4.0 you better be naked and skinny and not holding any bags. What has been observed by APTA studies here in North America is that, at as little as 3.3 people/metre sqd. choice passengers simply do not tolerate it and do anything to avoid it. Frankly, anything beyond 5-6 minutes at that level most people will find other options if they can. It is also disappointing that Transit Car builders are as bad as car companies and often inflate the actual amount of real standing room. The TTCin Toronto calculated that 25-33% of the stated standing room in their new Toronto Rocket subway cars is space that most passengers will only use in the most extreme cases. I read the Sky Train for Surrey website a while back and it’s writer quotted passengers densities of 6.0 and 8.0 people/metre sqd. to calculate capacity of the new Sky Train vehicles. Naturally my interest was peaked and found it odd that anyone who new anything about transit would use those figures. To my surprise on Bombardier’s website I actually saw those figures being used. What they do not tell people is that, those passenger densities are not really used to calculate real capcity but to simply measure maximum load mass factors on the track and vehicle frames. They do however use it to show capacity to pump up their numbers to potential customers however. I was disturbed that they would do this and found that Siemens, Alstom and others also use similar or other dishonest or inappropriate figures to pump up numbers to customers for various products, including LRV’s.

   I don’t mean to shit on people about this but, we need to start using more professional models and avoid these simple mathematical formula because it will harm more than it will help your causes to build and aquire better transit.

2. I. K. Brunel says:

   June 18, 2013 at 3:48 pm

   Trust our American cousins to play a game by their own rules, but this is how American transit planners operate. To see how backward the USA is in transit operation, only a few cities actually use low-floor trams.

   Portland, Houston, San Jose and the cities operating the wee Skoda Trams as (in the American vernacular streetcars) operate low-floor trams, with the rest still clinging to the date high-floor trams with raised platforms.

   Americans play by their own rules and get somewhat upset if others try to say; “there is a different way.”

   Mr. Zwei is quite right, that by reducing capacity for light rail, will leave the door open very wide for such transit modes as bus rapid transit (an oxymoron at best), personal rapid transit (the great American philosopher’s stone), monorail or Disneybahnen (which has a large American following) and other gadgetbahnen such as light metro.

   Planning for good public transit using light rail is not rocket science, but from what I have read, the American’s have fallen into a transit trap, using 1980’s academic studies, using 1970’s data for transit in 2013. The value of theses studies have been somewhat diminished by actual numbers from revenue operation, elsewhere, mostly in Europe.

   Calgary has been mostly ignored by American transit types and I can see why, the Calgary C-Train greatly out performs American new build light rail lines and as we all know, the Americans just hate to be beaten.

   What I see in the USA is much higher costs for new build LRT and a proliferation of expensive gadgetbahnen type transit systems, with American planners still debating capacity issues, long forgotten by the rest of the world.

3. zweisystem says:

   June 18, 2013 at 4:44 pm

   I agree with you, but the problem is that we do not have a level playing field.

   I was told personally by a transit specialist some years ago that the 4 persons m/2 standing was highest practical capacity of a vehicle and only in peak travel ,times; the 6 persons m/2 was only for extraordinary times like once or twice a year large events, etc. and only for short distances; the 8 persons m/2 figure was strictly used for theoretical calculations for brake testing etc. and not intended for revenue service. Optimal capacity would be about 2 persons m/2.

   Here lies the problem, when the SkyTrain Lobby quotes 6 or 8 persons per m/2 standing and then compares it with LRT, using the Vuchic formula, it makes LRT seem second rate and our American transit types don’t seem to understand this. We see this happening in Vancouver today!

   What really is sad is that there is great and very vocal disbelief with Karlsruhe’s ridership numbers. Equally sad is the North American notion that the more money one throws at transit, the better it will be, which certainly opens the door for all sorts of gizmobahnen to be planned for, especially the US penchant for monorails and even PRT is again on many transit planners lexicon.

   For any real transit debate, there must be a level playing field for transit data and that is just not happening.

4. Haveacow says:

   June 18, 2013 at 5:47 pm

   Guys, please cut out this anti US crap about their planners. Most American planners I know are far far superior to their foreign counterparts. Where they are really hampered is a system and generally under educated populace that treats anything foreign as of lesser quality or as a threat to their sacred way of life. I wonder how our planners or European planners would react to having nearly every public meeting broken up by people who believe that anything other road based transport is part of a grand conspiracy by the UN to take over their country. The Agenda 21 people threaten planners with bodily harm if anything non American like LRT is even proposed. Imagine public elected mayors who will not accept $10 million of federal funding to help build a combined downtown transit and an Amtrak station replacing a decayed concrete platform because it will add to the federal debt and attract more outsiders to their community. In fact it is only in the largest cities that normal transit planning can regularly take place. I wish these examples were the exception rather than the rule. It is not hard to see why the US has abysmal public transit in all but the largest cities. Even as bad as this can be they still tend to come up with the most interesting new ideas first, they take a good long time to implement them sometimes but they are very creative and need to be respected for that.

5. Haveacow says:

   June 18, 2013 at 6:16 pm

   In fact only Toronto and Ottawa will use 100% low floor LRV’s in North America. All other systems use 75% low floor vehicles. This is because very few operations want the high maintenance of 100% low floor vehicle trucks and all the extra costs associated having to relocate vehicle systems that are normally stored in or near the standard LRV trucks for ease of maintenance. Keep in mind that even LRT manufactheturers often than embellish the capabilities of their systems.

   Zweisystem replies: I have never really understood the need for 100% low-floor vehicles, when compared to a 75% low-floor design. I understand that 75% low-floor tram is both cheaper to build and maintain than its 100% low floor cousin. Maybe Cardinal Fang could answer.

6. eric chris says:

   June 18, 2013 at 8:58 pm

   I met with one of the councillors at the COV this spring. She was cordial. In the meeting it became apparent that the COV engineers don’t consider a tram or LRT length over about 35 metres practical for Broadway. This has some merit. It also matches the length of two 99 B-Lines operated in tandem (36 metres) by TransLink on Broadway during very busy periods.

   Siemens lists 250 passengers as the capacity of a 35 metre tram and this is also about the same capacity of the 36 metre sky train unit typically operated by TransLink. Based on the present two minute headway of the 99 B-Lines in tandem during peak hours when UBC is in session, the capacity of a tram fleet is 7,500 pphpd (60 minutes / 2 minute * 250 passengers) and 50 trams are required for the round trip time of 100 minutes (100 minutes / 2 minutes).

   Because the sky train is twice as fast as the tram operating on the roads, in relation to the tram fleet, only one-half as many sky trains are required to move the same number of passengers over one hour. For Broadway, TransLink would only have to operate “twenty five 36 metre sky train cars”.

   Even though, there are savings with sky train as far as minimizing the rolling stock, TransLink makes too much of this because going below or above grade to facilitate sky train is an astronomical cost. In addition, sky train is not independent from buses and requires buses.

   Consider UBC where there are 13 bus routes used to carry 6,750 pphpd at most (refer to Table 3.4 on page 25):

   http://transportation.ubc.ca/files/2013/04/Fall-2012-Transportation-Status-Report-25-Mar-13.pdf

   Obviously, just one tram line can meet the demand to UBC. Moreover, for the price of the subway to UBC, you could build one tram line for each of the four roads leading to UBC.

   You will notice in Table 3.4 that the 99 B-Line route carries one-quarter of the passengers to UBC in the morning while the remaining dozen routes carry the rest of the passengers. Furthermore, 75% of the seats on the buses to UBC are presently vacant, even during peak hours. To eliminate the cooked up overcrowding on the 99 B-Line, you just have to even out the demand amongst four routes which are what TransLink should be operating for the four roads to UBC.

   So, it is obvious that the overcrowding on the 99 B-Line is being contrived for TransLink in collaboration with COV engineers to make the case for the subway (sky train extension) to UBC. This is really tantamount to fraud.

   Let’s forget the fraud for a moment and stick to the 35 metre tram length as the constraint imposed by the COV engineers on Broadway to compare the four tram lines to the single sky train line in a subway to UBC:.

   Tram to UBC
   Four tram lines to UBC = 4* 7,500 pphpd = 30,000 pphpd
   Cost = $3 billion
   Elimination of 13 bus routes saving $50 million annually
   Addition of trams drivers costing much less the $50 million annually
   Reduction of about 14 billion grams of carbon emissions from the elimination of buses
   Saving in power costs as trams use 1/3 the electricity of the sky train
   Statistically for the 5 km median distance commuted in Vancouver, tram is faster than sky train in Vancouver

   Sky train to UBC
   One sky train line to UBC = 7,500 pphpd with an ultimate capacity of 15,000 pphpd with one minute headways
   Cost = $3 billion
   Increase in service hours for the 13 FTN bus routes costing more than $50 million annually
   Added staff and police to make sky train function at $$$$ millions more annually
   Increase in carbon emissions beyond the present 14 billions grams annually from the buses
   Increased power costs to run sky train fitted with linear induction motors

   Which is the best? Sky train according to the COV engineers!

   I have one comment: fire all the COV engineers who are a disgrace to their profession.

   Zweisystem replies: Please do not forget that SkyTrain cars operate in married pairs, thus 2 Skytrain cars equal the capacity of one modern tram. It is also worth mentioning that TransLink buys the cars on a per car basis, so one must factor in the calculation that a married pair of Skytrain cars costs slightly more than one modern tram.

   Another little know fact is trams, operating as a streetcar (in mixed traffic) tend to be 5% to 10% faster than buses, then add in signal priority, 15 second dwell times and reasonable lengths of reserved rights-of-ways; which give SkyTrain a speed advantage of not twice as fast, but maybe 25% faster than the tram.