Chapter III – part two: A large town

The main future movements

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We then turned to the first of the objectives set out in paragraph 177. We confined our attention to three types of movement, and their numbers as vehicle ownership approaches the maximum:

1. journeys to and from work
2. shopping journeys, and
3. industrial, commercial and business journeys.

These would not account for the whole of the urban movement by any means. Social and recreational movements, journeys to school, and many other casual and less regular journeys also take place. All these additional movements would together amount to about 20% of the whole, but either they tend not to occur during the peak periods of the three main classes of movement, or they are not great in volume, and therefore will not radically affect the pattern or size of the primary network.

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To ascertain the direction and volume of the three main kinds of movement we employed the same ‘gravity model’ technique that we used for Newbury. We divided the whole city into zones, and then estimated the inter-zonal movements that would be likely to take place having regard to the resident and/or employed population in each zone, the amount of floor space devoted to particular land uses in each zone, the distances between zones, and the travel habits of people in given circumstances. We do not suggest that this method based on estimates is a substitute for an actual travel survey, but since such a survey would have taken many months to organise and to process, it was the only method open to us.