The regeneration of Docklands in London began in 1986 with new office development and housing. How was the decision made to go for a novel railway system to serve this community?
Docklands Light Railway - part 1
So how would they choose between all the very different options? The GLC had developed a transport model for the whole of London.
Jill Beardwood, Greater London Council
The model works first by deciding how many journeys will be made for each small area of London. It then goes on and asks where those trips will go. If everybody who wants to do it in the morning peak were to go across Westminster Bridge then you would have 10,000 vehicles going across Westminster Bridge and nobody would make it at all. And in fact there is balance and adjustment. Because if we have a man who sets out and finds that it’s going to take him hours and hours and hours to get to work then that’s obviously not a plausible journey and we recalculate the journeys that would be made. We recalculate how they will be made and we keep going like that until the model has found a balance.
For many years, the GLC had been collecting data on journey times and traffic profiles within London. Number and type of vehicles were recorded at a wide range of sites across the Capital. Journey times were measured by using a special recording device to note journey characteristics for a car over a wide variety of specified routes. So the aim of this type of data collection was to help predict the demand through the GLC model. Meeting that demand then had to be calculated for the different possible transport systems, but in this type of project quantitative modelling can only be part of the story.
The problem with the bus service was that the image of the service did not really meet the LDDC’s requirements. Also, however much you improve the bus on the approach to the central area, by the time it got to this point you were into the gluepot in the congestion area, and this affected the reliability of the service.
Nevertheless, the data collected for travel times and costs were used in a cost/ benefit analysis on all the main options, with a rail system already favoured on the grounds of image.
The joint group which was looking at the whole question decided in the summer of 1982 to put together this package report on the assessment of the schemes. Now the scheme that we ended up with, which was a combination of this north-south and east-west link, the capital cost was £65m. When we added all the benefits together, we found that at best we could manage about £30m. So this project in the conventional transport cost/benefit terms only covered about 50% of its cost. In normal terms, that would have been the end of it.
This is where the story gains a new interest, because the objectives of the client set as a whole now come to the fore. One thing they were all agreed on was the need to convince the Government that this project was worth investing in. So they needed a set of figures produced by what would appear as objective means. What they had to do was to look for other factors that would produce the kind of answer they were looking for.
The factor they chose was a premium per job for the new jobs expected to be created. This was something to which all the parties could publicly subscribe. They could have built in the rising land values which would accrue as a result of improved transport, but this could have caused embarrassment to some of the clients. So an interpretation of the LDDC’s development objective was arrived at which expressed the expected benefits of the railway in terms of jobs.
They estimated about 9,000 additional jobs would be generated in the Isle of Dogs simply due to the railway. So the rest of the 50% of the £65m was justified by these additional jobs. In simple terms, it works out at a premium of about £2,000-3,000 per job.
So the proposal incorporating the revised figures was put to government. The timing of the impending Conservative Party Conference in autumn 1982 was believed by many to have been an important stimulus to a decision.
David Howell and I today announce the most significant development for London’s East End since the War, the development of rail links from the City into the Dockland areas.
We've seen then how objectives were formulated, in this case, a major one being the unity required to gain money from Central Government. Many alternative systems were possible, and modelling was used both for evaluating the alternatives and importantly as a weapon of argument to support a preferred option for reasons going beyond transport alone. Public decision-making often hangs on both these uses of modelling.
Completion of evaluation brings us to the point where the clients have in effect gone through one cycle of the method. In this case, they had achieved their goal of getting money, though perhaps not as much as desired. Now the client set has a choice. Before proceeding to implementation, another iteration could be gone through to reconsider the proposed routes and type of system now that the size of budget was known; alternatively, once the money was allocated, the railway could have been put out to tender, albeit with a rather vague specification.