THE UNDERGROUND SPACE AS A SPACE FOR ECONOMIC DEVELOPMENT

In city planning, public interest is also economic. Indeed, the city works if the economy exists and with density and functional diversity. The zoning is outdated. Unfortunately it is not always possible to mix industrial and logistic activities with housin. The result is an implementation of logistics areas in the periphery and longer transport time. For the tertiary sector, development is limited by the lack of space and the rising costs of land. In Paris, land pressure is as strong as land is scarce. For businesses, the challenge is this: find space close to the city with reasonable costs of acquisition and functioning. Sensitized to the potential of the underground space, some actors have become aware of the interest to consider a land "hidden", which is everywhere present. They begin to explore the resolution of economic issues through the underground solution. The use of underground space becomes even more interesting if underground quarries or limestone plateaus cross the territory. All actors would find interest: for economic reasons (sharing of the services costs, the energy saving thanks to the thermal slowness), for geographical reasons (strong identity of the site typifies quarry for companies), for land reasons (underground space available, sometimes already dug, costs of acquisition and lesser rent) and for ecological reasons (reduction of CO2 emissions, preservation of the surface). if innovation exists on a territory, the use of underground space could then become a powerful distimuishing factor for firms.