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Facts sheet 1 – Road versus rail - Capacity, average flow, density of use

Updated Dec 2016

This facts sheet compares capacity, passenger flows and freight flows by rail with those on the strategic road network and provides some anecdotal illustrations of the use that rail makes of its rights of way.  The associated spread sheet provides detail.


The line haul

At Waterloo 50,000 crushed passengers alight in the morning peak hour.  They could all find seats in 1,000 50-seat motor coaches.  Those coaches would occupy no more than one lane of a motor road.  At Waterloo there is room for 3 or 4 lanes in each direction. The waste is lamentable.

At Euston, 50,000 passengers alight all day. They would require no more than 2,500 coaches each with only 20 people aboard.  2,500 coaches could pass in 90 minutes in the space available on the approaches to the terminal but the railway has run out of capacity all day.

In the peak 3 hours some 500,000 passengers enter central London by surface Rail spread over 25 pairs of tracks.  If half the passengers arrive in the peak hour the average flow per inbound track is 10,000 passengers.  They could all fit in 200 50-seat coaches, sufficient to fill one fifth of the space available.

The contra flow express coach lane serving the Port Authority's bus terminal, New York, is 11 feet wide, one foot less than a standard motorway lane.  The lne is four miles long including 1.5 in tunnel.  It carries close to 700 45-seat coaches an hour, offering 30,000 seats - the same number as the crushed peak hour passengers arriving at Victoria Main line in traims requiring four inbound tracks.

A realistic capacity of one lane of a motor road is 1,000 75-seat coaches per hour.  They would provide 75,000 seats.  If travelling at 100 kph the head ways would be 100 metres or over 85 metres bumper to bumper; more than commonly seen on motorways. 

The Americans, particularly Don Morin, Head of Public Transport, US Department of Transport, concluded in the 1970’s that there is no movement corridor in the world where demand cannot be satisfied by one lane of a motor road dedicated to coaches.


Neither British Rail nor Railtrack would provide plans that would enable the areas of London terminals to be estimated and we have not enquired of Network Rail. However, at Waterloo probably the 21 platforms occupy an area 250 metres square, or thereabouts, a total of 6.25 hectares.  If 50,000 alight in the peak hour the density of use is 8,000 passengers per hour per hectare.

In contrast (a)   Victoria Coach station is said to be able to handle 10,000 passengers per hour, many with baggage, on one hectare.  (b) The area in front of Victoria Rail terminal used to handle 280 buses an hour on 0.2 hectare’s.  If each bus had 50 people alighting the density of use was 70,000 passengers per hour per hectare.

Hence it appears likely that the nimble bus would use terminal space very much more efficiently then can the cumbersome train.

If at Waterloo as many as 1,000 buses an hour were to arrive and if each needed to stand for as long as 6 minutes then there would need to be 100 bus bays. If they were spread over 3 levels there would be 33 bays per level.  That does not seem unreasonable. Perhaps the number could be halved if half the buses drove onwards, so avoiding the need for some of the passengers to alight.

Rail – equivalent express coach and lorry flows.

The calculations show that national rail carried an average flow equivalent to only some 340-400 buses plus lorries per day per track - a flow which is so small that it is fair to say that the network was, and is, substantially disused as it lies there basking in the sun of government subsidy. Here is the  typical calculation used in the spread sheet cited below and above.  For the year 2015 we have 63.8bn passenger-km and 17.8 tonne-km.  Dividing the pasenger-km by an average coach load of 20 yields equivalent express coach-km.  Likewise dividing the tonne-km by 12 tonnes per lorry yieldes equivalent lorry-km.  Adding the two provides 4,67 bn vehicle-km.  Dividing by the track length, 32,000 km, and by the 365 days per year yields an average daily flow of only 400 vehicles.

The calculations also provide the passenger and freight flows per track for rail and per lane for the motorway and Trunk road system averaged over the networks.  The ratios of the flows per lane to the flows  per track follow (a) ignoring and (b) including central reserves and hard shoulders as running lanes: 

Table 1 Ratios of flows per lane on the strategic road network to flows per track on the rail network for, 2015


Pass + Freight
(a) Ignoring central reserves and hard shoulders
(b) Treating central reserves and hard shoulders as running lanes

The rail network occupies corridors of intense demand and penetrates to the hearts of our towns and cities the density.  The strategic road network peters out on the fringes of urban areas.  Despite that the ratios show that the strategic road network is used two to three times as intensively per lane as is rail per track..

The spread sheets supporting this data are here

Anecdotal illustrations

Anecdotal illustrations of the inability of rail to make reasonable use of track include:

Welwyn Viaduct, shown opposite, on the East Coast Main Line,.  That viaduct has one track in each direction and carries 14 trains towards London in the peak hour (Letter from Railtrack dated 8th December 1999).  Those trains are equivalent to not more than 150 buses and coaches, enough to fill one sixth of one lane of a motor road.  Despite that trivial flow the viaduct limits the capacity of the entire route


   The Ouse Viaduct , Balcombe and St Germains Viaduct Cornwall .  These immense pieces of engineering, shown below, feature in the 1996 Network Management statements by Railtrack.  Railtrack were not been able to identify the use to which the structures are actually put but flows are likely to be much below those for the Welwyn viaduct.  Hence it is fair to say that the structures achieve little for the nation beyond photo opportunities. 

The capacity sections of The West Coast Main line

Page 3-2 of the Environmental Statement of Main Report supporting Railtrack’s case at the Public Inquiry into the West Coast Main Line Modernisation Programme provides the flows at the capacity sections. During the 18 hours 6 am to midnight these carry some 110 passenger trains and 55 freight trains, together equivalent to perhaps 2,500 buses plus lorries per day.  Despite that relatively trivial flow the limitation on capacity forced 35 to 40 other goods trains to operate from midnight to 6 am.  There are 3 running tracks at two of the capacity sections and two tracks at the third.  If the 18 hour flow, equivalent to 2,500 buses plus lorries, is split between just two tracks the directional 18 hour flow is 1,250 vehicles per track, sufficient to fill one lane of a motor road for about 75 minutes.


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