The 1986 LRTA Study: Bus ai??i?? LRT ai??i?? Metro Comparison

I thought I would again reprint this post from May 20, 2010 as it may clear up some major misconceptions about LRT capacity, especially our friend in Vancouver who are very confused about modern light rail.

There is an ongoing debate today that LRTAi??can only carry a limited number of riders and that the magic number for a subway is about 100,000 riders a day on a transit line. This may have been true in the 1970ai???s, but not the 21st century, where modern mufti-articulated low-floor light rail vehicles (tram is much easier to say!) are able to easily carry three or four times this number, thus negating the need for expensive subway construction, except on the most heavily used routes. If the LRTA found that modern LRT could carry over 20,000 pphpd in 1986, in 2010, in Karlsruhe Germany, one tram or LRT line on Kaisserstrasse was seeing traffic flows around 40,000 pphpd.

 

The 1986 LRTA Study: Bus ai??i?? LRT ai??i?? Metro Comparison

Posted by on Thursday, May 20, 2010 Ai??

A Vienna tram on a simple reserved rights-of-way.

The following is from the Light Rail Transit Associations hand book Light Rail Transit Today, comparing the operating parameters of bus, light rail, and metro on an unimpeded 8 kilometre route with stations every 450 metres. Using real data based on acceleration, deceleration, dwell time, etc., the study gives real time information for the three transit modes.

Please note: This study has been abridged for brevity and clarity.

The study assumes a vehicle capacity for a bus at 90 persons; LRT 240 persons (running in multiple unit doubles capacity); and metro at 1000 persons.

The time to over the 8 km. route would be:

  1. Bus ai??i?? 22.4 minutes
  2. LRT ai??i?? 18 .6 minutes
  3. Metro ai??i?? 16.3 minutes

The Round trip time, including a 5 minute layover:

  1. Bus ai??i?? 54.8 minutes
  2. LRT ai??i?? 47.2 minutes
  3. Metro ai??i?? 42.6 minutes

The comparative frequency of service in relation to passenger flows would be:

At 2,000 persons per hour per direction:

  1. Bus ai??i?? 2.7 minute headways, with 22 trips.
  2. LRT ai??i?? 7.5Ai?? minute headways, with 8 trips.
  3. LRT (2-car) ai??i?? 15 minute headways, with 4 trips.
  4. Metro ai??i?? 30 minute headways, with 2 trips.

At 6,000 pphpd:

  1. 1 Bus ai??i?? 0.9 minute headways, with 67 trips.
  2. LRT ai??i?? 2.4 minute headways, with 17 trips.
  3. LRT (2-car) ai??i?? 4.8 minutes, with 13 trips.
  4. Metro ai??i?? 10 minute headways with 6 trips.

At 10,000 pphpd:

  1. Bus ai??i?? 30 second headways, with 111 trips (traffic flows above 10,000 pphpd impractical).
  2. LRT ai??i?? 1.4 minute headways, with 42 trips.
  3. LRT (2 car) ai??i?? 2.8 minute headways, 21 trips
  4. Metro ai??i?? 6 minute headways, 10 trips.

At 20,000 pphpd:

  1. LRT ai??i?? 0.7 minute headways, with 83 trips.
  2. LRT (2 car) ai??i?? 1.4 minute headways, with 42 trips.
  3. Metro ai??i?? 3 minute headways, with 20 trips.

Comparative Staff Requirements on vehicles in relation to passenger flows. Station staff in brackets ().

At 2,000 pphpd:

  1. Bus ai??i?? 21 (0)
  2. LRT ai??i?? 7 (0)
  3. LRT (2 car) ai??i?? 4 (0)
  4. metro ai??i?? 2 (up to 38)

At 6,000 pphpd:

  1. Bus ai??i?? 61 (0)
  2. LRT ai??i?? 20 (0)
  3. LRT (2 car) ai??i?? 10 (0)
  4. Metro ai??i?? 5 (up to 38)

At 10,000 pphpd:

  1. Bus ai??i?? 110 (traffic flows above 10,000 pphpd impractical) (0).
  2. LRT ai??i?? 34 (0)
  3. LRT (2 car) ai??i?? 17 (0)
  4. Metro ai??i?? 8 (up to 38)

At 20,000 pphpd:

  1. LRT ai??i?? 69 (0)
  2. LRT (2 car) ai??i?? 34 (0)
  3. Metro ai??i?? 15 (up to 38)

Though the study is 27 years old and completed before the advent of low-floor trams (which decreased dwell times), it still give a good comparison of employee needs for each mode. Metroai??i??s, especially automatic metro systems do require a much larger maintenance staff than for bus or LRT and when one factors in the added high cost of subway or viaduct construction plus higher operational costs, Metro only become a viable proposition when traffic flows exceed 16,000 pphpd to 20,000 pphpd on a transit route.

Claims from other blogs that automatic metros can operate more frequent headways than LRT are untrue; automatic metros can not operate at higher frequencies than LRT, but if Metro is operated at close headways in times of low traffic flows, they do so with a penalty in higher maintenance costs and operational costs.

Taking into account the almost universal use of low-floor trams, operating in reserved rights-of-ways, combined with advances in safe signal priority at intersections; given an identical transit route with equal stations or stops, LRT operating on the surface (on-street) would be just as fast as a metro operating either elevated or in a subway at a fraction of the overall cost grade separated RoWai??i??s. Also, automatic (driverless) metros, though not having drivers have attendants and station staff, which negate any claim that automatic metros use less staff than light rail.

The LRTA study does give good evidence why LRT has made light-metros such a as SkyTrain and VAL obsolete.

http://www.railforthevalley.com/latest-news/zweisystem/the-1986-lrta-study-bus-lrt-metro-comparison/

Comments

3 Responses to “The 1986 LRTA Study: Bus ai??i?? LRT ai??i?? Metro Comparison”
  1. Haveacow says:

    I have 2 small points to make. After traveling to Karlesruhe and talking to their transport people I can assure you the 40,000 was from a mathematical estimate not a acurate count. However, Kaiserstrasse does average (mean) 26000-34000 during a peak period, usually the AM. The lateset median count I had was 26500-28400 during the AM peak. The counts had been dropping recently because of the constant “Yellow Wall” (a local term from the huge numbers of their yellow LRV’s clogging the street) that was affecting local business by detering shopping as well as slowing down the whole rail system. They are now putting most of the LRV’s in a “T” shaped LRT tunnel. This whole complex project is to be complete around 2018-19 and is expected to cost around 640 Million Euro’s. The rest of the LRV surface traffic will travel down a parallel street Kreigstrasse that will have a grassed private centre median surface right of way. Underneath Kreigstrasse will be a car and truck tunnel with underground highway like interchanges leading to downtown. A section of Kaiserstrasse, centred around Europlatz (located at the the core of the “T” junction) will become a pedestrian only mall. There will also be a short private surface right of way leading to the central rail station (at the base of the “T”) This project was delayed many times due to court challenges and officially started in 2010. It was originally planned to start in 2003.

    Sorry guys it is true that, MOST NOT ALL, automatic rail systems do operate at a greater frequency than MOST NOT ALL, manned LRT systems however, before all the Skytrain people gain too much hope, this comes at a BIG, operating cost mostly due to maintenance issues. What normally happens in the design phase of these automatic systems is that because of the higher than operating frequency and tempo, system capacity usually suffers because it is believed that the greater frequency will make up for the expensive capacity issues. It is no accident that the Skytrain and Canada Line Automatic transit lines have stations platforms and train lengths that are generally smaller than nearly all of the operating and planned LRT systems. Never mind the conventional full scale subway and metro lines. This means that the fuctional capacity, not the larger theoretical capacity, is often very quickly or more quickly maxed out (sound familiar) than in a manned LRT system. Thus causing great expansion pains due to the very high one-time capital cost of expanding the system’s functional capacity(does this also sound familiar).

    Manned systems tend to have higher operational capacity because the cost of expanding the system does require transit companies to hire more drivers and that is by far the single biggest operational cost and is often feared, due to the almost unpredictable spastic nature of the ever increasing costs of health and pension plans. If more drivers are going to be needed it is often more practical to make sure that you do not have to add future capital spending on top of the increased operational cost of the extra drivers. So more often driver based rail systems make sure that extra passenger capacity is added at the planning phase to maximise current as well as future planned passenger capacity and the resulting operating cost per passenger or passenger-km/mile than in driverless based rail systems.

    Zweisystem replies: Smaller automatic metros do travel at high frequencies because they have to to generate the capacity. To maintain operational capacity smaller SkyTrain cars must travel more often, which increases maintenance costs.

    My contact in Karlsruhe has told me that on occasion (holidays) the route saw ridership near 40,000 pphpd and yes he did mention the yellow wall. My contact has also told that the subway, as designed, will be difficult to handle the high ridership on that portion of route and trams may yet again trundle down Kiasserstrasse; but that decision will not happen until the tunnel opens.

    I am trying to get figures from Calgary comparing how many drivers they have and how that compares to SkyTrain’s 170 full time attendants

  2. eric chris says:

    @Haveacow, yes, as you say, the functional capacity of regular LRT or tram transit is higher than the capacity of sky train for a very fundamental reason – it takes 10 minutes to 20 minutes to typically reach a rapid bus or sky train stop spaced 1,000 metres to 2,000 metres apart.

    To illustrate, if 250 people arrive every 10 to 20 minutes at a sky train or rapid bus stop but the rapid bus or sky train departs every two to five minutes (people crush on the next available rapid bus or sky train as they don’t know whether the next rapid bus or sky train is going to be full) and many rapid buses or sky trains depart too empty while many depart too full.

    This is not good transit design and transit has to be slowed down to match the time that it takes people to reach the transit stops. TransLink operated by simple accountants is clueless and is wasting our money with sky train and rapid bus.

    As far as costs go, driverless sky trains require many regular bus drivers to get passengers the rapid bus and sky train stops located miles apart. Operating costs for rapid bus and sky train (direct and indirect) far exceed LRT and tram operating costs – that is, LRT and trams take buses off the roads while sky train and rapid buses add regular buses.

    Fast transit only does one thing – it creates urban sprawl in the same way that freeways do. Vancouver stopped building freeways to curtail urban sprawl and TransLink through greed to increase density for developers to build moon high towers along sky train lines is creating sprawl with fast transit (Marchetti effect).

    http://www.bbc.com/future/story/20121018-hidden-rules-of-human-progress/4
    http://www.cesaremarchetti.org/archive/electronic/basic_instincts.pdf

    This has created a revolt in communities which don’t want Vancouver to become another over populated and sprawling Toronto. Look at all the happy protesters opposed to urban density along sky train lines:

    http://www.straight.com/news/429121/vancouver-residents-rally-planning-changes-city-hall-protest

  3. Haveacow says:

    As a former Toronto resident I can tell you it is the suburbs outside of the new city of Toronto (formarly the Muninicipality of Metropolitan Toronto) that sprawls. The higher density inside the city is by design and a good one. By increasing the density along Toronto’s Grid Mainstreets (a term call Mainstreating) you get rid of all the old sprawl oriented development that use to be there. This makes your transit more effective, increases the tax base and leaves the interior neighborhoods untouched. The city has managed to actually slowly increase its population while until recently most other inner cities had declined. You see there is almost no green field land inside the boundary of Toronto to develop, the rest is saved in large parks and untouchable river valleys in Conservation Areas. So TO has only brown field land to develop when it is not on the main street grid. What happens on a daily basis is over 50% of the car and truck traffic is from outside the City of Toronto Boundary. The efficient grid network of buses in the old inner suburbs of the City of Toronto (Scarborough, North York, Etobicoke, East York and York (City not York Region) is what generally gives the TTC its great numbers. All thesde routes feed and connect to the Subway and RT many times over. Most of the horrendous Sprawl is in York, Durham, Peel and Halton regions. Toronto’s main issue is the lack coordination between the regional governments and the city of Toronto as well as a political problem in the form of a grand left vs. right political battle at all levels. The subway vs. LRT fight for example is primarily a politicial one between Conservatives who gennerally whant subways and to dismantle any social spending so taxes remain lower and be able to drive where and whenever they want just as they always have. While the left of centre politicians who want to gennerally increase density and social spending as well as force drivers as much as possible out of their cars. Which they believe will improve the environment. Once Toronto has fully implemented most of their new LRT lines, I guarantee most of the people will wonder why we were fighting it in the first place.

    Vancouver has a serious problem that anyone who can read a map can see. Vancouver is running out of cheap developable land and quickly. I bet in 20 years Vancouver density will greatly exceed that of Toronto just out of shere need. Both in Toronto and Vancouver it is no accident that green roofs and roof top farming is being heavily promoted as farm land continues to be gobbled up. Here in Ottawa I am part of that new group of people who are raising kids in the core of the city. These old streetcar neighborhoods here are booming while growth in the burbs has slowed. People are getting tired of having to drive 5 minutes just to pick up milk and bread while we can walk in less than 3. My corner store is a Loblaws with 200,000 square feet that is right up on the side walk and looks like a series of small stores with the parking in the back. The old downtown suburban relationship is changing in the large Ontario cities primarily because gas is getting too expensive and people want full and complete walkable neighbourhoods. Plus developers will just not build new urbanist neighborhoods in the burbs fast enough.

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