Urban Development of the Subsurface: Sketches from Switzerland
Alexander Ruch
ETH Zurich, Basel, Switzerland
Abstract: The space which cities need to develop is limited. People’s demand for space to live and work in and generally enjoy is growing all the time (the amount of settled space in Switzerland increased twice as fast as the population between 1985 and 2009: at 23% compared with 11% (BFS: Die Bodennutzung in der Schweiz, Resultate der Arealstatistik [Ground Use in Switzerland, Results of Land Use Statistics]). In addition, immigration is on the rise, traffic requires ever more space, and pollution — particularly as a result of noise — is increasing exponentially, while the loss of land available for agriculture and the destruction of the landscape call for the spread of settled space to be curbed, for density and concentration, and for an emphasis on working inward and even downward when developing land for settlement. The city needs to use the space the subsurface offers for its development. The areas of the subsurface that might be used for construction are also associated with usable rock, geothermal energy, and drinking water.
Policy is little concerned with using the subsurface, urban planners are not familiar with it or its potential for urban development, the lack of geological expertise regarding the subsurface can result in damage (see section 4.4 below concerning StaufenimBreisgau), and spatial planning and related law pay scant attention to it as well. Any use made of it tends to be uncoordinated. This results in conflicts over use, and there is a growing danger the potential of the subsurface will not be fully exploited. The subsurface needs to be factored into spatial planning at all “levels” without exception, and particularly into planning in relation to urban development.
There is a lot of talk about three-dimensional urban development, but this is about applying the methods and instruments associated with (spatial) planning beyond the space at and above the surface and putting them to productive use for the underground dimension of space too. It is a case of ascertaining how far the law needs to concern itself with urban planning in relation to the subsurface, how well the existing instruments associated with spatial planning address the specific issues of using the subsurface, and to what extent special regulations regarding the subsurface are required at the various levels of planning. Other questions include how the various demands for use might be coordinated, to what extent the need for an overview calls for a new methodology, how far the law concerning the limits of land ownership and delimiting responsibilities and interests as regards use of the subsurface remains adequate, and whether 3D surveying provides sufficient support. These and similar issues will be addressed in the rest of this document, with special reference to the situation in Switzerland.
Key words: spatial planning, subsurface use, 3D cadastre, conflicts over use
