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Re: [WorldTransport-Focus] road v rail

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  • Eric Bruun
    Mr. Withington, A few quick comments: 1) Trains are not fragile. The UK runs an exceptionally old fleet in poor condition. 2) Your citation of approximately
    Message 1 of 4 , Nov 4, 2002
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      Mr. Withington,
       
      A few quick comments:
       
      1) Trains are not fragile.  The UK runs an exceptionally old fleet in poor condition.
       
      2) Your citation of approximately 2000 vehicles per lanel per hour is not valid for two reasons:
       
      First, automobiles are much smaller than buses, and also operate with unacceptable spacings and safety regime for a public transit operation, as evidenced by the large number of accidents..
       
      Second, and more importantly, you keep confusing "way capacity" with "station capacity". The capacity along a motorway where there is no periodic stopping at stations is always much higher than the station capacity (for any mode) and is usually not the limiting factor in designs. Rapid transit systems regularly can reach 50mph or higher between stations with extremely high safety and capacity with an average speed of 30 mph or higher. It would be very hard to get anywhere near an hourly capacity of 50,000 persons per hour at the same level of safety if hundreds of buses were trying to run on the same single-lane alignment.
       
      Have a look at the Lincoln tunnel -- the buses move at 30 mph, often even slower. Plus this is only an operation with no passenger stops, way capacity is not relevant to replacing rapid transit service, the station capacity must be similar as well.
       
      Eric
       
       
       
       
      ----- Original Message -----
      Sent: Thursday, October 31, 2002 4:21 PM
      Subject: Re: [WorldTransport-Focus] road v rail

      I reply to Simon and Eric by annotating the texts:
       
      Simon's
       
      > Some replies to Mr Withington's last but one message.
      >
      > (a) I am not quite sure why a coach is supposed to use as much fuel (8 mpg) as a 44 tonne lorry.  The consumptions I quote come from enquiry in the industry.  Intercity coaches are said to achieve 10 mpg in uncongested rural road conditions.  That is said to rise to 15 mpg if the air conditioning is turned off.  Large lorries in uncongested motorway conditions are said to achieve 8 miles per gallon
      >
      > (b) Mr Withington's statistics are unsupported by most other authorities. For example the director of the railfreight company EWS recently claimed on a radio programme that lorries produce 7 times as much CO, 4 times as much N2O, 5 times as much particulates, and twice as much CO2 as trains for the equivalent amount of goods carried. Yes, he may have an interest, but I still believe that he knows what he is talking about. 
       
      My data on rail freight fuel consumption comes from NETCET citing the National Atmospheric Emissions Inventory for the DETR.  That showed rail freight twice as fuel, efficient as road freight provided the drag in and out to the rail head was ignored.  If the drag in and out averages 10 miles then rail freight and road freight would use similar amounts of energy.  That went substantially unchallenged by Railtrack's immensely expensive inquiry team at the Inquiry  into the West Coast Main Line Modernisation Programme.
       
      As an example of the way official bodies, such as the Strategic Rail Authority, misuse data see page 6 of the SRA's Strategic Plan.  There the bar chart purports to show that an intercity train produces one quarter the CO2 of buses.  However.  It turns out they are comparing intercity trains with average buses.  Average buses have an occupancy of only 9 passengers and return only 5 to 7 miles per gallon on account of stopping every couple of hundred metres on congested city streets.  Hence those buses return about 50 passenger miles per gallon.  Compare that with an intercity coach with 20 passengers returning 200 passenger miles per gallon.
       
      I then inquired of the SAR how they had estimated the fuel consumption for rail.  They could or would not say.  So I rest with my 1990 data provided by BR.  That shows provincial services returned the equivalent of 64 passenger miles per gallon, Network South East, 83, and intercity, 112, compared with the intercity coaches value of 200.
       
      In any case the SAR comparison has no value for there is no possibility at all of attracting people out of buses stopping in town centres into intercity trains.  Furthermore the SAR comparison overlooked the fact that 25% of electricity is from nuclear leading to nuclear waste in place of CO2.

      (c) Mr Withington didn't answer my question of who would pay for maintenance of rail formations converted to busways. Buses are at present entitled to a refund of most of their fuel duty. The only way in which such maintenance could be financed cost-free is by taking the roadspace from other vehicles and thus securing a reduction in traffic levels. 
       
      Fact sheet 8 showed that track maintenance for rail is 5 to 10 times as expensive as would arise if the rail function were carried out by buses and lorries.  At the moment it is the non-rail user who generally pays for the railways and the road user who pays 5 to 7 times the cost of providing the roads.

      (d) Rail infrastructure only seems expensive because most of its usage has been creamed off by road traffic whose taxes don't cover a fraction of their environmental and social costs.  Passenger miles remained constant for decades.  After privatisation use increased by 30%.  The Environmental costs of rail per passenger or tonne-km are many times that of the cost of road see above and previous analyses.  The reason the railways appear environmentally kind is that they are substantially disused - carrying the equivalent of only 300 buses plus lorries per day per track averaged over the network.  New movement carried by car could never go by rail since the new movement is to a dispersed land use. 

      (e) Congestion is NOT the reason why coaches at present don't provide a decent service, at least outside hotspots like London. (Places like Cambridge have congestion too, but use of railways wouldn't help here because they don't reach the city centre anyway.) At present coaches take 60 minutes between Cambridge and Peterborough, as opposed to 50 minutes by train to which one has to add about 15-20 minutes walk at Cambridge and 5-10 minutes at Peterborough. Trains run every hour, there are just 3 coaches a day. If the railway was used by coaches it would take longer than now because the distance by rail is 45 miles
      as against 35 miles by road. I must insist, generally coaches provide a much slower and more circuitous service then does rail.
       
      (f) What's this about removing rail subsidies ? And if this were to happen it should be by doubling patronage and leaving fares alone rather than the reverse (this would be quite feasible if we taxed motoring at an appropriate rate).  Rail fares would have to at  least double without loss of passengers if subsidy were to be removed.  Why on earth should the tax payer subsidise rail travellers (generally the better off) when there is a four times cheaper option providing 4 times the capacity using less fuel and providing a 3 times lower casualty cost per passenger-km

      Finally, Mr Withington is correct in referring to rail cost escalation. However this is not an argument against rail so much as an argument against the administrative framework for rail that was foisted on us by the Major government. In Northern Ireland, where the railways are still nationalised, the recent reopening between Belfast and Antrim came out at rates comparable to what
      BR used to charge. We could get rail projects done cheaply in the rest of the UK too if we got the system right -- especially if we had a rolling programme (as happens with roads) instead of dealing with every project separately after years of agonising.
       
      This scandalous cost escalation has nothing to do with John Major.  Instead it has everything to do with incompetent estimating supported by the noble assumption that the tax payer will pay anything to keep the railways going.  After all we make 11 journeys per head per year by rail compared with 17 by bicycle.
       
      Paul W
       
      Eric's
       
      1) Check the capacity versus speed curves in, for example, Vuchic, 1981, "Urban Public Transportation: Systems and Technology". Buses can not move at the same speed as a long train and maintain an equally safe braking regime. Speed must be kept down. The BRT in Bogota, in order to maintain both speed and capacity actually uses two lanes in each direction.
       
      It is a common sight to find 2000 vehicles per hour per lane using the Chiswick Flyover.  It is common knowlege that 1,000 vehicles an hour will travel at 50-60 mph with comfort in one lane of a motorway.  Don Morin  Head of Public Transport Department of Transport Washington DC and many others concluded concluded as long ago as the 1970's that one lane of a mtor road dedicated to coaches could carry in excess of 50,000 passengers per hour at speeds of 50-60 mph.  The research is voluminous but need not have been because there is a daily  practical illustration of the capacity of motor roads clear for all to see.
       
      2) The entire wall of buses going through the Lincoln Tunnel to the Port Authority Bus Tunnel carry no more passengers than could easily be acommodated with one light rail line. 3) Virtually all of the bus lanes which carry very large numbers of people require extraordinary effort to keep them moving smoothly. Buses have to be platooned at stops, disabled vehicles must be moved extremely quickly, etc. Also, the high passenger numbers quoted in Lima, Sao Paolo, etc. come from.  There is no railway in the world carrying 50,000 passengers per hour per track at 50 mph.  That is not achieved by buses in the Lincoln tunnel because of insufficient demand.  A boken down bus is a rarity - easy to move, or drive round, compared with a broken down train.  Trains are immensely fragile - witness a paralysed rail network following the recent storms compared with business as usual on most roads.

      > crowding and discomfort levels which would never be tolerated in rich countries. I don't oppose these systems, but they are not appropriate if you are trying to attract persons out of their cars.  Rich people seem to tollerate intollerable conditions on most commutor trains. However if they realised that they could all have seats at one quarter the cost if only the railway lines were removed in favour of motor coaches then there would be a riot.

      > 4) I do not dispute that buses can be stored in similar amounts of space as trains. However, for either mode, more storage is required if one tries to allow independent departures. The Port Authority facility is large because each bus must be able to depart unimpeded. If one can use first-in and first-out, then buses are very space efficient. On the contrary independant departures means that the nimbled bus needs a smaller space/time foot print than the train where many carriages must wait together.
       
      5) How would one reliably get 1000 buses into a central area station during  peak hours? If they are using their "flexibility" to come from all direction and merge just before the station, there better be priority for buses throughout the city. If they are using the a grade separated right of way and operating on a common trunk for long distances, then they must either move slowly or extra lanes must be added. If a tunnel is the only available separated right-of-way then one must build a large bore tunnel and use electric or dual-mode buses. No bus system on earth could carry the number of people the Central Line in London carries with two tiny tunnels.  My calculations and the daily observations open to all of us show that the bus needs one quarter the space of the train. 
       
      Do you have the dimensions of the tunnels, the passenger flow and the average speed of these trains please? Probably the width is at least 3 metres and the speed rather low e.g. averaging perhaps 20 mph inside the circle line - probably the moving floor space provided by the trains is equivalent to only 300 buses per hour? e.g. 30 trains per hour each with 8 carriages = 240 carriages/hr, equivalent to 300 buses.

      Regards
       
      Paul W

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    • Paul Withrington
      Eric - I hope you do not mind rejoinder by way of more annotation to your comment. (Heaven knows why this is coming out blue - but I have been upgraded) 1)
      Message 2 of 4 , Nov 6, 2002
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        Eric - I hope you do not mind rejoinder by way of more annotation to your comment. (Heaven knows why this is coming out blue - but I have been upgraded)
         
        1) Trains are not fragile.  The UK runs an exceptionally old fleet in poor condition Fragility is relative.  After last weeks storms we had a completely paralysed rail system and thousand stranded by Eurostar - an extremely modern system.  In contrast it was business as usual on the roads.  The fragility of rail to the wrong sort of snow, leaves onthe line, weather too hot or too cold, or even to the effect of a falling birds nest is legendary.  (They seek to solve the birds' nest problem by installing plastic hawks).  In contrast road transport is robust.
         
        2) Your citation of approximately 2000 vehicles per lanel per hour is not valid for two reasons:
         
        First, automobiles are much smaller than buses, and also operate with unacceptable spacings and safety regime for a public transit operation, as evidenced by the large number of accidents.
         
        Second, and more importantly, you keep confusing "way capacity" with "station capacity". The capacity along a motorway where there is no periodic stopping at stations is always much higher than the station capacity (for any mode) and is usually not the limiting factor in designs. Rapid transit systems regularly can reach 50mph or higher between stations with extremely high safety and capacity with an average speed of 30 mph or higher. It would be very hard to get anywhere near an hourly capacity of 50,000 persons per hour at the same level of safety if hundreds of buses were trying to run on the same single-lane alignment.
         
        Have a look at the Lincoln tunnel -- the buses move at 30 mph, often even slower. Plus this is only an operation with no passenger stops, way capacity is not relevant to replacing rapid transit service, the station capacity must be similar as well.
        I insist - 1,000 buses/hr can can travel at 50-60 mph in one lane of a motor road.  (60 mph and 1,000 per hour implies an average headway of 105 yards - often seen on a motorway). 
         
        As to station capacity - the area in front of Victoria rail station handled 280 buses in the peak hour on half an acre in the 1960s.  (Lord knows what is there now since I seldom go to London).  If each bus discharged 50 people then the density of use was 28,000 passengers per acre.  In contrast waterloo manages 50,000 passengers in a vast area - so vast Railtrack said they had no drawing of it at the public inquiry into the WCMLM.  However if the platforms alone occupy an area 250 yds sq then the density of use is less than 4,000 passengers per acre, one seventh that achieved by the bus.  If anyone has more exact dimension of rail terminals I would welcome the detail.
         
        Alternatively try this calculation - A bus can discharge its passages at the rate of 1 per 1.5 seconds so that a 70 seat bus would take less than two minutes to disgorge a load of commuters.  If we allow five minutes then with buses arriving and departing at the rate of 1000 per hour we need 83 bus bays at Waterloo.  Those could be spread over 3 levels giving 30 per level - hardly enough to frighten the pigeons.
         
        Regards Paul W
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