Overview
The assessment of traffic demand from individual or multiple traffic generators should be based on well-founded information about specific traffic generation rates (i.e. on values based on experience). Within Switzerland and the other continental European countries, no well documented measurements of traffic generation are available to those practices in this field, particularly for the assessment of the effects new uses on traffic. Data acquisition and reporting need to be standardised, in order to facilitate the recording and compilation of such rates.
The study will develop a guideline for the measurement of trip generation of individual generators under Swiss conditions. The study will also suggest a system for the collection and distribution of such surveys.
The study was worked out in the following main sections:
• Analysis of the literature and directives already available internationally
• Compilation of the explanatory variables for the individual types of utilisation
• Discussion of the acquisition and provision of traffic generation rates
• Development of a Swiss standard to document the measurement of traffic generation rates
Funding
Results
Research into the literature has shown that only a few references and results are available in relation to the standard acquisition and provision of traffic generation rates, and that these are difficult to transfer. In the USA and the UK, information about traffic generation is systematically collected and, to some extent at least, published. This information is instructive for Swiss design practice, but is not directly transferable, for various reasons, e.g. because of the difference in spatial structures. There are practically no comparable collections of data within the continental European countries. In order to assemble the bases for calculating the generation rates specific to particular uses correctly, the traffic-generating factors associated with these uses will have to be determined. The uses that are most significant from the point of view of traffic planning were studied in greater detail.
This involved land developments involving various functions of use, and individual, traffic-intensive setups in order that generation rates can be made available systematically, it is advantageous to set up a database. As well as storing the information, and making it available for enquiries, this database can then be used to follow up and process the data under verifiable conditions.
The main purpose of this database will be to establish parameters specific to traffic generation for various set-ups and land developments, and to make these available to the planning process. Appropriate tools are required in order to put the methodology into practice. These include the developed standard SN 640 004, “Documentation relating to the Measurement of Traffic Generation Rates (Metadata)”. This standardises the metadata used to describe the increases in traffic generation, and establishes the reference quantities that are to be used to report the traffic generation rates for the individual types of use.
This standard provides uniformity in the documentation of traffic generation rate measurements, with the aim of being able to store the data in a database and to enable comparisons to be made in the measurement results.