One of FLUA’s aims is “to seek the integration of other public transport services with Fen Line services”. This paper sets out a vision for integrated public transport appropriate for East Anglia in the 21st century.
Various forms of mass transit, such as light rail and busways, have been proposed for the Cambridge area. Here we set out the case for a combination of heavy rail and new technology.
Most journeys are by an individual or a very small (e.g. family) group. Although there will typically be several wanting to travel between the same two towns at roughly the same time, they are unlikely to all be travelling between the same locations within those towns.
This is why cars are a popular mode of transport in less densely populated areas: car owners can travel at any time, and take a reasonably direct route, including travelling at comparatively high speed on main roads between towns. Cars and vans will always be the best solution for people who need to take more with them than they can reasonably carry. However, there are several problems with universal car ownership, including congestion in towns and the amount of land occupied by parked cars, so ideally there would be a public transport system that makes it unnecessary for families to have more than one car, and unnecessary for many people to own a car at all.
New towns are planned to have every dwelling and business within 400 metres (about 5 mins walk) of a bus stop. However, with linear bus routes and the need for each bus to have a reasonable number of passengers, most journeys will not be direct and services will be infrequent or non-existent at off-peak times.
Driverless vehicles are already being trialled; a service operated by driverless “pods” that ran at low speed on public roads and higher speed on dedicated tracks would allow an on-demand service available 24/7 to be offered. Such a service could be used for local journeys and act as a feeder service to rail for longer journeys. It would be nearly as convenient as car travel, and without the problems of finding a parking space. Routes that do not have enough demand to support a bus service (e.g. orbital routes between villages around Cambridge) could be included in the network. The pods can be made small and light enough that dedicated tracks would take up less space than a busway; bridges, viaducts, and tunnels would also be smaller and therefore cheaper. Even within those constraints, there could be higher-capacity vehicles to serve peak demands.
Users of the system should be able to book journeys ahead or simply “turn up and go”, via an app or website or by presenting a credit card at a stop.
The experience of someone arriving at a stop not having pre-booked would be similar to someone arriving at the lifts in a tall building, i.e. they choose their destination on a touch screen and are told which vehicle to get into. Depending on how busy the system is, they might be sharing the vehicle with other passengers who will be dropped off on the way.
When booking ahead, for instance to travel to a meeting, they could specify the arrival time and the system would then plan a route and say when to be at the stop from which they would depart. For local journeys there would be no change of vehicle required; longer journeys could be partly by rail.
There are a number of features that follow from the requirement for an on-demand 24/7 service, at a price similar to bus services.
A major part of the cost of bus and taxi services arises from the need to employ drivers. The business model for buses relies on the vehicles being reasonably full, so the cost is spread between a number of passengers, but we are proposing a system that serves more sparsely-populated areas and is available at times of low demand, and costs less than a taxi fare. Therefore the vehicles need to be self-driving.
Vehicles need to able to overtake other vehicles that are picking passengers up or dropping them off; on a guideway that requires stops to be off-line. Also, there need to be places for idle vehicles to wait (and recharge their batteries); these places need to be distributed around the system to cater for “turn up and go” passengers. A system using rail or other physical guidance would need an unreasonable amount of pointwork, so a flat surface (e.g. tarmac or concrete) is needed. Rubber tyres (particularly new forms that shed fewer particulates) would have the advantage of being able to work with steeper gradients, including on ramps connecting elevated or underground sections to stops at ground level.
The system needs to be able to run at low speed (maybe 15-20 mph) on public roads and at higher speed (50 mph or more) on dedicated guideways. Using the road network allows the system to be rolled out more quickly and to serve areas where construction of guideways would be infeasible. Initially it could be restricted to specific roads (as bus routes are) because detailed mapping of the roads is likely to be needed. An alternative could be “virtual tramlines”, possibly with guidance (buried wires, perhaps) installed in the carriageway.
There will need to be a standard specification for the guideways and for some aspects of vehicle performance when on the guideway. Parameters would include: guidance system; width and height (within which vehicles must fit, including allowance for vehicle suspension and accuracy of the guidance); axle weight; cruising speed; acceleration (from stops) and braking; maximum gradient; and minimum radius of curves.
There will also need to be communications standards for vehicle-to-vehicle (e.g. for platooning and at junctions) and vehicle-to-control-room (e.g. for telemetry, traffic monitoring, and, in exceptional conditions, remote control of vehicles), also an open interface to a journey planning and booking facility. Where a journey is partly by rail the standard interface to the rail industry’s system for third party ticket sales can be used.
There have been various proposals for busway, light rail, etc, systems which could form the basis of a guideway network. Greater Cambridge Partnership is currently planning to construct three new off-road busways on routes previously planned to be parts of the Cambridge Autonomous Metro. These busways are planned to be flat tarmac with as yet unspecified guidance technology but also wide enough (3.65 metres, or 12 ft, per lane) for conventional buses; a guideway (or “podway”) for the kind of system proposed here could be considerably narrower and built to carry lighter vehicles, thus reducing the cost.
One of the GCP routes, the Cambridge South East Transport scheme, would be better implemented as heavy rail. Another, linking Cambourne to west Cambridge, has attracted much opposition to the intended route and some of its traffic would be abstracted by East-West Rail. The third, linking Waterbeach to north Cambridge, would be suitable as a first implementation of the technology.
From near Cambridge Regional College the route goes north-east to Butt Lane where there is a short stretch along the road; that part could instead be on a viaduct, removing the need to upgrade the road and install two traffic-light junctions. Where it leaves the road, the buses are planned to visit the park-and-ride site, which will extend the journey time; this detour would not be necessary for pods unless they had passengers wanting to join or leave there. It crosses two more roads via traffic light junctions; these could be made grade separated instead. It then crosses the A10 at a roundabout and passes through the new town to the “station quarter” where it is proposed a new rail station will be built. From there the podway could run beside the railway to the current station, giving residents of the new town access to the current station until the new station is opened. It is planned that the current station would close at that point, after which the podway would provide those living near it with transport to the new station, as required by the new station’s planning permission.
A spur could be added serving the northern part of the new town and the Research Park, taking advantage of the system’s freedom from needing to be organised as linear routes. At its southwestern end the route could be extended along the current busway to serve the science park, business park, and Cambridge North station, and in the other direction to Histon and beyond, as was planned for the Cambridge Autonomous Metro. It could be extended into the city, and into villages such as Histon, along public roads. Tunnels under the city, as previously proposed for various metro systems, could be an option to reduce journey times within the city – stops would be on the surface, linked to the tunnels by ramps, thus avoiding the higher cost of underground stations.
Further development of the system could begin with connecting other settlements to rail stations, e.g. Chesterford Research Park – Great Chesterford – Genome Campus – Whittlesford Parkway or Melbourn – Meldreth, including systems within towns that have a railway station on the outskirts, such as Ely and Littleport. Availability of the system at both ends of a journey would reduce the need for passengers to take their bicycle on the train. Eventually these routes should be linked to form a single network, so the system can provide “rail replacement” transport when required, reacting to incidents much more quickly than is possible for buses.
Orbital routes such as Waterbeach – Cottenham – Bar Hill – Cambourne should also be added, reducing the need to travel via the city.
Cambridge Autonomous Metro: https://cam.consultationonline.co.uk/wp-content/uploads/sites/119/2020/02/CAM-Consultation-Leaflet-2.pdf
One of the responses to the call for proposals: https://dromos.network/wp-content/uploads/2021/04/CAM-Media-Pack-3.pdf – this proposal meets many of the requirements though not on-street running; maximum speed on the guideway is 75 km/h (46.6mph)
Autonomous vehicle technology R&D: https://zenzic.io/