Characteristics of traffic of facilities used intensively by the public are put together on the base of specific documents and additional surveys of the subject according a typology.
Basic principles are developed to assess reliably the impact of facilities used intensively by the public on traffic and environmental impact.
The definition of concepts such as "heavily frequented sites", "types of location" or "types
of site occupation" is based on important research of Swiss, German, French, Austrian
and Belgian bibliography. This is systematically analysed according to certain parameters
relating to movement and defined in advance.
In other respects, this work is based on a study of actual situations carried out in German-
and French-speaking Switzerland. At the same time as evaluating existing documentation,
surveys were undertaken (questionnaires, counting, etc.) for all 15 case studies.
These analyses make it possible to highlight the categories of heavily frequented sites;
the characteristic determinants of resulting movement according to the type of installation; the idea of statistical data input aimed at the continuous improvement of databases
concerning heavily frequented sites; and certain information relevant to the future planning
The analyses showed that the amount of traffic generated by a heavily frequented site depended largely on its location. Centrally situated sites generated a higher number of journeys for each person (m² or sitting place) and a modal distribution (proportion of public transport, cyclists and pedestrians) significantly higher than in the case of the surrounding zones (factor 5). The area of commercial attraction is significantly smaller for the centrally situated heavily frequented sites. Altogether, centrally situated sites generate fewer vehicles-kilometres per surface unit than in
the case of heavily frequented sites situated on the outskirts. After private cars, pedestrian
mobility is the most frequently used means of transport. This accounts for an average of more than 20% in the case of centrally situated sites. Public transport accounts for more than 10% only in locations where the quality of these services is good to very good.
The recommendations from research which are useful for planning and running future
heavily frequented sites are the following:
- The planning of these sites primarily concerns regional development. The public authorities must preserve enough centrally situated building land in order to avoid the proliferation of constructions on the periphery. Positive and negative planning go hand in hand. The investors and users are solicited regarding the adaptation of their strategies of expansion and setting up. The increase in centrally situated establishments and a distancing from the "philosophy of concentration" are part of this.
- The measures linked to transport planning permit the optimisation of the initial access structure of a site. Such measures are, for example, the insertion of heavily frequented sites in existing pedestrian and cycling zones; the dependability of direct and frequent public transport to and from the shopping zone and the limitation of the number of journeys and/or official parking places; and the management of the latter in relation to existing road capacity and environmental inconveniences.
In order to improve the value of available data concerning the generation of movement caused by heavily frequented sites in Switzerland – which is still unsatisfactory – the research team suggested recommendations for collecting such data. At the same time as statistical indications of the site (dimensions, activities etc), active data should be gathered, such as the number of people/journeys, the modal distribution, resulting traffic, etc.
The introduction of regulations concerning building permission for new constructions or for changes in use of existing ones will help to ensure a systematic improvement in the value of the data concerning the generation of movement caused by heavily frequented sites in Switzerland.
Even at the conclusion of this study, the data collected concerning movement caused by heavily frequented sites may be qualified as unsatisfactory. The reasons for this are the lack of and imprecision of data on the one hand, and the strong reticence of the majority of managers of these sites to collaborate in a case study and to provide or give access to the basic information necessary. The 39 case studies were made up of 13 heavily frequented sites whose anonymity was preserved (data from various sources) and 11 coming from a previous study on similar research.
However, 15 heavily frequented sites consented to be analysed as examples for this study. Various enquiries were carried out in these sites (questions to clients/visitors, analyses including questions on accessibility, partial counting of the number of people etc.) Each of these 15 cases is listed in a descriptive document.
In spite of the relatively important number of 39 cases studied, the characteristics observed had to be rapidly put into perspective after a further comparative analysis, since they proved to be atypical cases.