Between the Poles

Geospatial World Forum: Land administration in Germany to include 3D cadastre by 2013

At the Geospatial World Forum in Amsterdam, Peter Creuzer, Director State Survey of Lower Saxony, gave a very interesting introduction to land management in Germany and some of the things that are on the horizon. 

Germany has about 82 million citizens, or about 229 people per km², and the population has been declining since 2003. It has about 64.5 million parcels (land properties) valued at about €9 trillion.  About 48% of households own land.  The land administration system handles about a million transactions per year. 

Germany has the same problem that other jurisdictions have, urbanization, but it has limited land resources.  It loses about 77 hectares/day to urban sprawl.

Land administration in Germany is comprised of two parts, a land register and the cadastre.The land register includes information about owners, land use, encumbrances, and other legal obligations.  The cadastre includes the land parcel geometry, owneship, buildings and public restrictions.  The objectives of the land administration system are security of tenure, some revenue for the government, and support for a transparent planning process.

There are some interesting future goals, one of the most important of which is enabling sustainable development.  This includes land consolidation and revitalization of older cities.

Another major initiative is revision of the land taxation system which is expected to be completed by 2014.  The alternatives that are being considered are taxation based on market value (which is what is used in Ontario), a fixed tax, and a combined system.

There is also a new data model underway based on ISO and Open Geospatial Consortium (OGC) standards referred to by the abbreviation AAA, which stands for AFIS (uniform geodetic reference), ALKIS (uniform cadastre), and ATKIS (uniform topography).  By 2013 the data model will include support for a 3D cadastre and will include the CityGML standard.  It will be accessible via OGC web services; WMS, WFS, and others.

Germany is also working on being compliant with the EU INSPIRE directive.  There is a pilot in progess involving the Netherlands, Lower Saxony, and North Rhine Westphalia.

Towards a 3D cadastre (parcel fabric) for Singapore

In April 2006 at a conference organized by PDS on Pangkor Island in Malaysia, Professor Alias Abdul Rahman from the Universiti Teknologi Malaysia talked about 3D cadastres, which are more important in Asia, where urban population densities tend to be higher.  Professsor Alias outlined three approaches for dealing with 3D cadastres

• Administrative tag model - Integrate 2D spatial with tagged information for strata
• Hybrid model - Integrate a 2D cadastre with topological information about 3D structures
• Full 3D model- Requires a complete overhaul of the cadastre to incorporate three dimensions

Professor Alias had developed a pragmatic solution based on the hybrid model that supported topological queries including adjacency using off the shelf products (COTS), for example, Oracle Spatial and AutoCAD Map 3D.

Singapore's motivation for a 3D cadastre

Yesterday at the Asia Geospatial Forum conference here in Jakarta, Soh Kheng Peng of the Singapore Land Authority, which is reponsible for the cadastre (parcel fabric) in Singapore, gave a riveting presentation on the reasons for the importance of a 3D cadastre in Singapore and what the Singapore Land Authority is doing to implement a full 3D cadastre.

Defining the 3D cadastre problem

Soh Kheng Peng made it very clear that a 3D cadastre is in the cards for Singapore, for several reasions.

1. Land developers are being very creative and packaging complex volumetric parcels both underground and above ground.  
2. Current survey techniques cannot capture accurate 3D coordinates.  
3. The current 2D GIS used to capture and store cadastral information is unable to represent volumetric parcels.
4. All strata boundaries are not in the cadastral GIS, making it impossible to perform effective spatial planning for national development goals.

Underground space is heavily used and underground density is increasing.  Underground lots are getting very close to each other and accurate delineation of boundaries is required.

First step toward a full 3D cadastre

The Singapore Land Authority has identified priorities for the first step toward a 3D cadastre.  The first priority is to change survey procedures to enable surveyors to capture accurate 3D information.  This means adopting new technologies and changing legal requirements for surveys.  The next priority is to collect sufficient information in a 3D GIS to support national planning goals.

Basis for virtual Singapore

I've blogged about other cities' efforts to create 3D urban models, for example, Vancouver, and a recent software release focussed on conceptual design for 3D urban environments.  These have been undertaken for planning purposes, for zoning and other bylaw enforcement such as viewports or right to light, or one of the most remarkable recent efforts, Sydney Down Under, for emergency and disaster planning.  But in Singapore Soh Kheng Peng said that the "future 3D cadastre will be the fundamental information for building virtual Singapore."  This means that virtual Singapore will not only be a representation of Singapore in 3D, but will incorporate the legal 3D parcel fabric.