A new vision on cadastral data model

Land administration systems are evolving towards an integrated land management paradigm designed to support sustainable development. In this paradigm, land administration delivers four functionalities: land mapping, land registration, land valuation and land development, each with specific data elements, with the cadastral data model at the core. Cadastral data modelling potentially plays a key role in both data and business management in modern land administration systems. However, some modifications to existing data models could potentially improve their capacity to deliver sustainability. Firstly, the existing role of land parcels and properties as core building blocks in land administration systems can be significantly extended to make the cadastral fabric available to assist management of a wider range of rights, restrictions and responsibilities by using the concept of legal property objects: an entity defined by a law or regulation which relates to a physical space on, below or above the earth. This can be interpreted as a new land related commodity, land parcel or a property. Secondly, although land parcel and property identifiers are key elements of interoperability within land administration subsystems, the paper argues that they have not yet given appropriate emphasis in cadastral data models. Among the identifiers, spatial identifiers can potentially simplify data exchange and work flows among land administration functionalities on a much wider basis. Finally, the paper discusses technical issues raised by changing the cadastral model: the advantages and disadvantages of spatial identifiers, possibilities for spatially presenting rights restrictions and responsibilities, and consistency between various legal property objects.8-13 October 2006