Objectives

During the past years it has been noted that the intention behind various 3D Cadastre activities, often include more than 3D Cadastre in the narrow sense. The ambition is to realize full life cycle support in 3D involving the following steps (order differs per country):
  1. Develop and register zoning plans in 3D
  2. Register (public law) restrictions in 3D
  3. Design new spatial units/objects in 3D
  4. Acquire appropriate land/space in 3D
  5. Request and provide (after check) permits in 3D
  6. Obtain and register financing (mortgage) for future objects in 3D
  7. Survey and measure spatial units/objects (after construction) in 3D
  8. Submit associated rights (RR)/parties and their spatial units in 3D
  9. Validate and check submitted data (and register if accepted) in 3D
  10. Store and analyze the spatial units in 3D
  11. Disseminate, visualize and use the spatial units in 3D
The main objective of the Working Group is to establish an operational framework for 3D Cadastres. The operational aspect addresses the following issues:
  1. A common understanding of the terms and issues involved. After the initial misunderstandings (due to lacking shared concepts and terminology) in the early days, the concepts should now be further refined and agreed on, based on the ISO 19152 Land Administration Domain Model (LADM, which provides support for 3D representations).
  2. A description of issues that have to be considered (and to what level) before whatever form of 3D Cadastres can be implemented. One could think of a checklist for the implementation of 3D Cadastres. These will provide 'best practices' for the legal, institutional and technical aspects. These findings will be translated in basic guidelines for the implementation of 3D Cadastres.
By means of pursuing these issues we hope to have a fruitful exchange of ideas. There exists not a unique 3D Cadastre. In all cases for the establishment of such a cadastre legal, institutional and technical issues have to be addressed. The level of sophistication of each 3D Cadastre will in the end be based on the user needs, land market requirements, legal framework, and technical possibilities. Therefore, in line with ISO's LADM it is our objective to explore the optimal trade-offs between 2D en 3D cadastral solutions (the full replacement of a 2D Cadastre by a 3D Cadastre is not an issue, but we need to address the issues that arise in the transition zones).

We will focus primarily on professionals involved in geo-information and cadastral issues in 3D. This community will also provide the contributors to the Working Group. Access to this interest group is open to all. Once the results become more tangible the FIG-community at large will be our public.

Within the Working Group the concept of 3D Cadastres with 3D parcels is intended in the broadest possible sense. 3D parcels include land and water spaces, both above and below surface. However, what exactly is (or could be) a 3D parcel is dependent on the legal and organizational context in the specific country (state, province). For example, in one country a 3D parcel related to an apartment unit is associated with an ownership right, while in another country the government may be owner of the whole apartment complex and the same apartment unit is related to a use right. In both cases there are explicit 3D parcels, but with different rights attached. A third country may decide not to represent the apartment units with explicit 3D geometries at all (and the 3D aspect is then 'just' conceptual). A more formal definition: A 3D parcel is defined as the spatial unit against which (one or more) unique and homogeneous rights (e.g. ownership right or land use right), responsibilities or restrictions (RRRs) are associated to the whole entity, as included in a Land Administration system. Homogeneous means that the same combination of rights equally apply within the whole 3D spatial unit. Unique means that this is the largest spatial unit for which this is true. Making the unit any larger would result in the combination of rights not being homogenous. Making the unit smaller would result in at least 2 neighbour 3D parcels with the same combinations of rights.