The link between car parking and greenhouse gas emissions (GHGE) is ambiguous and has been poorly studied. Car parking policies can impact on car mobility in different ways: firstly, a shortage of car parking supply can involve modal shifts - but the traffic related to the search for parking bays may increase; secondly, a restriction on car parking supply in city centres may make the outskirts more attractive and therefore contributes to urban sprawl; and thirdly, in extreme cases as in Paris or London, car parking conditions or policies can also influence households' choice of vehicle. Furthermore, it is estimated that private car mobility currently contributes to 14% to GHGE produced in France. France has set itself the goal toreduce by 75% its emissions by 2050. In this context, the aim of the research undertaken by SARECO has been: to define the effects of car parking management on climate change; and to determine what car parking policy is most sustainable. A first step has been to assess car parking policies usually led by French cities. The widely shared objectives of those policies are to make parking conditions easier for residents, to dissuade commuters from driving to work and to facilitate the car accessibility of city centres for visitors. These objectives induce three remarks: car parking regulations discriminate between different types of car users but not between the distances covered by car users; the strain on car parking has mainly been blamed on commuters whereas commuting trips only represent 25% of car kilometres driven in France every year; and car parking regulations have mainly focused on city centres, and therefore a restricted amount of kilometres. As an example, the study estimates that regional shopping centres generate some 15% of private car kilometres. The attempts to assess the different parking measures usually implemented tend to show a positive (though limited) tendency as regards the reduction in GHGE, in particular because they have contributed to enhance town centres and therefore to limit urban sprawl. However, the effects of some measures, such as the development of park and ride facilities or on-street parking charging, remain uncertain; in particular, the effects in the short run could be opposite to the long-term consequences. Visitors constitute a major stake as regards parking policies: their trips constitute a major part of the car kilometres travelled every year but their behaviour (distance travelled, car occupancy, motives, elasticity to pressure on parking supply, willingness to use a different transport mode) is poorly known and understood. This work shows that, beyond the optimisation of the currently led policies, there exists a much wider scope for intervention through parking regulations. The second step of the research consists of studying in turn the following themes: measures in favour of "green cars": how car parking regulations can sustain car-sharing, car-pooling and "clean" vehicles; parking taxes and their influence on travel behaviour and urban planning; a reduction in private car park ownership and development of public car parks; and restrictions on car ownership. This work is based on a review of different parking schemes implemented in England, Germany, Switzerland and the USA: effectiveness when assessment is available, discussion of possible pernicious effects, adaptability to other contexts, etc. For the covering abstract see ITRD E145999
Samenvatting