Bordeaux Métropole’s method for identifying densification potential on existing sites
Practical notebook 16: (Re)developing productive activities in metropolitan areas
Thierry Petit, November 2024
Bordeaux is a dynamic and attractive city. Many companies are looking to expand in the area, but are faced with a shortage of land for a variety of reasons. Bordeaux Métropole’s urban planning agency, A’urba, has created an atlas and mapping application to provide an accurate estimate of the land potential in the metropolitan area. The aim of this approach is to highlight the expertise, projects, actions and tools being developed by both the public and private sectors, with a view to reconciling land conservation and economic development.
To download : cp16_ok_bat_web.pdf (7.3 MiB)
A mapping approach
To identify under-utilised business sites, the Bordeaux metropolitan area relied on a survey and analysis of land by a’urba, the city’s urban planning agency. The agency mapped 19 business parks in strategic sectors, mainly in the north and east of the city. This long-term project, which has been underway since 2013, led first to the production of an atlas and then more recently to an online application enabling the zones in question to be viewed from different angles. Aerial observations have been supplemented by field surveys and data from the tax authorities (MAJIC database), enabling owners to be identified, indicating land use patterns and providing information on floor area declarations, the number of building levels, the year of construction, etc. The cartographic approach has made it possible to define a synthetic occupation density ratio at the zone level (floor area ratio) in addition to information on floor areas, as well as a qualification of the quality of the buildings according to three categories (dilapidated, old, recent).
The floor area ratio is then compared with the average for similar sites to determine whether the area is theoretically under-occupied. On the basis of a list of under-occupied areas, a’urba commissioned a consultancy firm to make contact with the companies on site to gain a better understanding of how their business is organised and what their needs are, and also to suggest ways of pooling facilities. As part of the ‘Aire’ call for expressions of interest, Bordeaux Métropole wanted to mobilise some of this land to carry out densification projects, particularly on the Cheval Quancart site.
Other examples in France and abroad
Audiar, the Rennes urban planning agency, has carried out a similar survey (20 sites) representing a quarter of the city’s business parks, introducing criteria based on employment density.
AURG, the urban planning agency for the Grenoble region, carried out an in-depth study of the Saint-Égrève business park to assess the maximum building density based on physical criteria and various regulatory constraints. Out of 25 hectares of land, the study identified 50,000 square metres that could be developed, i.e. 20% of the surface area. For its part, in May 2021 the borough of Bexley in Greater London carried out a study into the intensification of its industrial areas, defined here as the increase in activity space per site and the intensification of their occupation. The aim of the study is to provide guidance on the intensification of industrial sites, which will be incorporated into Greater London’s Supplementary Planning Document to help developers maximise the use of industrial land.
Points to watch
A major inventory is still required. Available statistical sources are not sufficient and local knowledge is essential. Determine who is responsible for updating the information.