Capacity on the London Birmingham corridor

In the evidence that Philip Hammond gave to the Select Committee enquiry into High Speed 2 he stated that the business case of HS2 depended on the need for additional capacity on the London-Birmingham corridor. He claimed that the only way to achieve that is to build a new railway line (which might as well be a high speed one). Express coach was not mentioned once.

Let’s explore the capacity argument a little. The current HS2 plans are based on a maximum of 4 trains per hour (see section 2.3.4), each of which can be up to 400 meters long with seating for 1,100 people (see section 3.2). The proposed capacity per hour is therefore 4,400. The number of trains will no doubt increase as the line extends further north in the future, but this provides a useful base-line for the additional capacity that is required.

Interestingly a single lane of the existing dual three-lane M40 motorway (or on the M6/M1 motorways) running directly from Birmingham into London could carry 63,000 people using today’s express coach technology which is fifteen times as many people as proposed by High Speed 2 above. The capacity requirement of HS2 could be achieved using a single 87 seater coach per minute.

In practice such a lane would be very under-utilised and it may be appropriate to also make this lane available to taxis, other coach services and any other vehicles with 3 or more occupants. Given that there is likely to still be available capacity then it may be desirable to allow vehicles with only one or two occupants to use the lane on payment of a dynamic fee which would vary with demand. Such an express toll lane system is being developed in Los Angeles as part of their Metro Expresslanes project on El Monte Busway and Harbor Transitway which is used by the Silver Line (a bus rapid-transit line). The fee income can be used to maintain the route and make public transport fares more attractive.

This proposed M40 service would build on the success of the current Oxford-London coach services which operates along part of the corridor. Vehicles could optionally call at and new and existing intermediate coachway stations associated with the key settlements along the route, such as the Thornhil Park and Ride site serving Oxford, and the new High Wycombe coachway interchange which is in the planning stage. The M1 route would be able to call at recently completed Milton Keynes Coachway interchange and at other new coachway stations.

There would be no huge interchange at the end of these corridors as would be the case with HS2 – vehicles would start from a variety of places around and within Birmingham and elsewhere and mesh with local transport including the underground and bus services within London.

Here is Philip Hammond’s response to a question about the need for HS2. In fairness to the Secretary for State, I am including his response in it’s entirety.

Capacity per traffic lane using express coach

The maximum throughput of a single motorway lane is currently about 1,800 vehicles per traffic lane per hour (based on the Highway Code 2 second rule) with a throughput of people of about 2,880 (based on average occupancy of 1.6 people per vehicle). Let’s compare this a system based on express coaches with an average occupancy of 30 people (current average occupancy of a coach on the National Express network) and a more cautious 4 second spacing between vehicles which allows for a throughput of 27,000 people per traffic lane per hour. Using larger 87-seater double-decker coaches (as used on the Oxford-London route) and yield-management fares (which would increase occupancy to more like 80%) the throughput would be increased to 63,000 people per single traffic lane per hour. Using these available technologies a single lane of a motorway would be able to carry three times more people than on 20 lanes of traffic using private cars at low occupancy.

The effectiveness of coach lanes is demonstrated by the M4 bus lane, which used to carry 21% of the people entering London on the route but which was  which was suspended because it was ‘virtually empty’ even though taxis and motorcycles were also allowed to use the lane.

It is unfortunately that this opportunity to  ‘sweat the assets’ of our motorway network has being ignored to date. One of the key arguments in favour of High Speed 2 is that there is not sufficient capacity on the roads. High Speed 2 will initially offer four trains an hour with 1,100 seats per train and will therefore only provide 4,400 additional movement per hour. Plans to realign the A14 and to build the ‘Lower Thames Crossing‘ are also based on the assumption that the current roads are operating at capacity. It is of concern that a key recommendation relating to the recent widening of the M25  was that a strategic express coach system should be developed to avoid this additional traffic capacity being absorbed by greater private car use. This strategic coach system has not been developed and the government is now discussing addressing other ‘pinch points’ on the M25.

The government is supporting ‘vehicle platooning’ that allows cars follow each other more closely. No one seems to be predicting exact what increase in traffic flow rates will be achieved other than to say that “the utilisation of existing road capacity will also be increased with a potential consequential reduction in journey times”. The EU is currently funding a project called ‘Safe Road Trains for the Environment‘ which is January 2011 allowed a single vehicle to follow feet behind a truck. Let’s be generous and assume that it will double throughput to one vehicle per second resulting in 5,760 people per traffic lane per hour which is still way below what can be achieved with today’s express coach technology. The researchers claim that this convoying system will allow drivers to ‘read, rest, eat, make phone calls, and so on’ but this is of course exactly what people are already doing in express coaches!

Coach systems of this sort also achieves huge energy saving compared to the car and fares would be much lower that the cost of rail and the private car. It allows people to work and rest while traveling which benefits ‘productivity’ which is one of the reasons the government gave for increasing motorway speed limits.

Roads to prosperity?

In 1989 a White paper titled ‘Road for Prosperity‘ (frequently referred to incorrectly as ‘Road to prosperity’) discussed the problems of increasing transport demand and in particular increased demand from ‘road users’. It famously went on to outline the ‘biggest road building program since the Romans’ to alleviate the predicted congestion on our roads. This got both middle England and environmentalists up in arms by the mid 1990s with major road protests at Twyford Down and elsewhere with most of the remaining schemes being quietly canceled soon after.

This post is not about that period however, but there is a nugget of truth tucked away on page 2 of the introduction of the 1989 report which is worth discussing. It points out that: “The different scales of road and rail activity is also important. Road transport is responsible for twelve times more passenger travel and ten times more freight movement than rail. A 50 per cent increase in rail traffic would reduce road traffic by less than 5 per cent. Rail has an important contribution to make but it is not a panacea for congestion on inter-urban roads“. It turns out that by 2000 the situation had become even more skewed. By then distance traveled by road was now fourteen times more than passenger mileage by rail.

It is therefore a fact that to accommodate a 7% increase in passenger traffic though increased use of rail would need an expansion of rail capacity by a factor of two.

During the election all three political parties were pushing for rail expansion. In the spending review huge investment in rail was protected, including Crossrail and High Speed 2 with at £13.1 billion per year. How far is this going to get us?  High Speed rail is not attractive from a carbon perspective, it is hugely expensive, will take an age to get planned and built and there are signs that middle England is rising again. We even have the bizarre situation where those enemies, the Campaign for Better Transport and the Association of British Drivers seem to actually agree on something, ie that High Speed Rail is not a sensible project in a cost-constrained world.

The 1989 report was right that rail couldn’t deliver, its conclusion that we need a massive road’s program is of course not. We are recommending moving from cars on roads to coaches on roads. Every coach creates its own space on the road by taking cars off it. This means that we can almost use exactly the same infrastructure as that designed for use by private cars.

This will deliver big environmental, reduce congestion and increase productivity very quickly. It will benefit huge numbers of people travelling intermediate inter-urban distances all across the country, rather than focusing all the benefit on two or three major cities (London, Birmingham and possibly a few more). In this blog we will be both promoting the vision and also the infrastructure work required to deliver it. This infrastructure work is mainly about the creation of Coachway Interchanges which in some cases can be simple bus stops close to junctions, in other cases may be as fancy as the Milton Keynes Coachway.