Car dependency

Automobile dependency implies that cities where automobiles are the predominant transport deny their residents not only freedom of choice about the way they live and move around the city, but also that the culture of automobile use has produced a kind of addiction to them. The analogy is made with addictions to harmful substances and activities because of the well-known law of diminishing returns in relation to increasing use or participation: the more that is used, the less of the desired effect is gained until a point is reached where the substance or activity has to be maintained to remain 'normal', a state of dependency.

When it comes to automobile use, there is a spiralling effect where traffic congestion produces the 'demand' for more and bigger roads and removal of 'impediments' to traffic flow, such as pedestrians, signalised crossings, traffic lights, cyclists, and various forms of street-based public transit such as streetcars (trams).

These measures make automobile use more pleasurable and advantageous at the expense of other modes of transport, so greater traffic volumes are induced. Additionally, the urban design of cities adjusts to the needs of automobiles in terms of movement and space. Buildings are replaced by parking lots. Open air shopping streets are replaced by enclosed shopping malls. Walk-in banks and fast-food stores are replaced by drive-in versions of themselves that are inconveniently located for pedestrians. Town centres with a mixture of commercial, retail and entertainment functions are replaced by single-function business parks, 'category-killer' retail boxes and 'multiplex' entertainment complexes, each surrounded by large tracts of parking.

These kinds of environments require automobiles to access them, thus inducing even more traffic onto the increased roadspace. This results in congestion, and the cycle above continues. Roads get ever bigger, consuming ever greater tracts of land previously used for housing, manufacturing and other socially and economically useful purposes. Public transit becomes less and less viable and socially stigmatised, eventually becoming a minority form of transportation. People's choices and freedoms to live functional lives without the use of the car are greatly reduced. Such cities are automobile dependent.

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Wikipedia