Once cars are gone, streets will seem much wider, as here in Valladolid, Spain
The Need to Convert Existing Cities to the Carfree ModelIf we are to achieve a sustainable world, we will probably have to eliminate nearly all urban automobile usage. (It is to be hoped that some use of cars can continue in rural areas, as the alternatives are not attractive.) For a thorough discussion of the issue, see the "Wicked Cars" chapter in Carfree Cities. Battery-powered, self-driving cars threaten to delay the change to carfree cities. It must be understood that most problems with conventional cars apply equally to "green" cars.
The ChallengesThe Reference Design for carfree cities can guide the development of most new-built cities, of which there will be quite a few in South and East Asia. In most of the rest of the world, populations are roughly stable, and few new cities will be needed.
Unfortunately, the conversion of an existing city to the carfree model is a good deal more challenging than the construction of a new city. The provision of good public transport is essential in a city of more than, say, 200,000, people, as the distances will be too great to walk under normal circumstances. (This does not rule out the possibility of a bicycle-centric city of considerable size, but few climates are mild enough to make this an attractive option for most people; likewise, hilly terrain further challenges cyclists in many cities.)
Public transportation technology was fairly mature a century ago, but the improvements since then make it an even more attractive option. In particular, the recent development of trams that do not require overhead wires makes the installation of street-running trams an excellent option for existing cities, one that will work very well once the trams are no longer obstructed by cars.
The matter of freight delivery will always be the most difficult technical challenge in the conversion of a city to the carfree model. In most cases, the continued but restricted use of trucks, especially those modified for urban use, will be accepted, as is commonly the case in carfree districts today. Any number of measures can be taken to limit the intrusion of trucks, but their continued presence will always be a less-than-ideal condition. For this reason, serious consideration should be given to reducing or eliminating the delivery of freight over city streets except by bicycle-based vehicles, which can have some form of battery assist.
Cities with an extensive network of canals, such as Amsterdam, can consider requiring the delivery of freight by water, and some changes in this direction have been seen in Amsterdam during the past 20 years. Sufficient restrictions on the use of trucks can further encourage this trend.
In some cases, the tram network can be used to deliver freight during off-peak hours. This technology is actually more than a century old, and today's few implementations seem to work quite well. It is less easy to modify a metro system for use in freight delivery, although it is not out of the question in cities such as Berlin, where most metro lines are not deep underground. In cities like London, where the tubes run far below the surface, the metro system probably cannot be adapted for freight delivery.
Of course, the garnering of public support for the change to carfree cities will usually be the most difficult task. If it is to succeed, it will only be on the basis of community support, which may take some years to develop. The implementation of regular carfree days serves to remind people of the large improvements in quality of life that arise when cars are gone, even if only briefly. The Lyon Protocol, which is discussed at length below, is one basis for converting cities to the carfree model over a span of years on the basis of community support.
Six Articles on Carfree ConversionsIn 2009 I wrote a series of six articles for CarBusters magazine. With minor changes, all six articles are linked immediately below.