Towards a property registry 3D model in Portugal: preliminary case study implementation tests

Abstract

The 3D concept emerged as a key concept within geoinformation science. 3D geoinformation has been proved to be feasible and its added value over 2D geoinformation is widely acknowledged by researchers from various fields. Even so, 3D concept merits still need to be exploited further and more specific applications and associate products are needed—such as within property cadastre, our ultimate field of interest. The growing densification of urban land-use is consequently increasing situations of vertical stratification of rights. Traditional 2D cadastral models are not able to fully handle spatial information on those ownership rights in the third dimension, thus 3D cadastre has been attracting researchers to better register and spatially represent real world overlapping situations. A centralised distributed cadastral management system, implementing a 2D cadastral model, has been conceived by the national cadastral agency in Portugal: the so-called SiNErGIC. The authors seek to show that there is room though for further investigation on the suitability of a 3D modelling approach, incorporating both topological-geometric representation and legal/administrative components, capable of handling the overall multipurpose cadastral reality in Portugal. This paper focuses primarily on the clear identification of some case studies illustrating the pertinence of such an approach; first technical implementation tests were carried out.