Key words: Cadastre, Standards, 3D, 3D Cadastre, 
		Inventory
		SUMMARY 
		In this paper, the background, set-up, and a preliminary 
		analysis of the survey conducted by the FIG joint commission 3 and 7 
		working group on 3D-Cadastre, 2010-2014 is presented. The purpose of the 
		survey is to make a world-wide inventory of the status of 3D-Cadastres 
		at this moment (November 2010) and the plans/expectations for the near 
		future (2014). Sharing this information improves cooperation and 
		exchange of experiences and supports future developments in different 
		countries and cadastral jurisdictions. The FIG working group will repeat 
		the survey in four years time to evaluate the actual progress. In the 
		questionnaire the concept of 3D-Cadastres with 3D parcels is intended in 
		the broadest possible sense. At the moment of writing, 36 completed 
		questionnaires have been received. Another detailed questionnaire survey 
		is being conducted among the eight cadastral jurisdictions of Australia, 
		and the results from these are also presented and compared to the 
		international situation. At the moment of writing, all completed 
		Australian questionnaires have been received. 
		1. INTRODUCTION 
		In the past decade various activities have been 
		conducted related to 3D-Cadastres. The start of the international 
		awareness of this topic was marked by the workshop on 3D-Cadastres 
		(sponsored by FIG commissions 3 and 7), organized by Delft University of 
		Technology in November 2001. This was followed by virtually a session at 
		every FIG working week and congress afterwards (stimulated by the 
		2002-2006 FIG working group on 3D-Cadastres). Within cadastral 
		organizations this was paralleled by on-going developments at Cadastral 
		organizations in many countries to provide better 3D-support. The 
		increasing complexity of infrastructures and densely built-up areas 
		requires a proper registration of the legal status (private and public), 
		which only can be provided to a limited extent by the existing 2D 
		cadastral registrations. Despite all research and progress in practice, 
		no country in the world has a true 3D-Cadastre, the functionality is 
		always limited in some manner; e.g. only registering of volumetric 
		parcels in the public registers, but not included in a 3D cadastral map, 
		or limited to a specific type of object with ad hoc semi-3D solutions; 
		e.g. for buildings or infrastructure. 
		At the FIG Congress in April 2010 in Sydney it was 
		decided to form again a working group on 3D-Cadastres in order to make 
		further progress with the subject; see Section 2 for more details of 
		this working group. The registration of the legal status in complex 3D 
		situations will be investigated under the header of 3D-Cadastres. 
		Starting point of the working group is the observation that increasingly 
		information is required on rights, use and value in complex spatial 
		and/or legal situations. 
		There are several 3D-Cadastre scoping options, which 
		need to be investigated in more detail by the working group, and the 
		result will define the scope of the future 3D-Cadastre in a specific 
		country:
		
			- 
			
What are the types of 3D cadastral objects that need 
			to be registered? Are these always related to (future) constructions 
			(buildings, pipelines, tunnels, etc.) as in Norway and Sweden or 
			could it be any part of the 3D space, both airspace or in the 
			subsurface as in Queensland, Australia?
 
			- 
			
In case of (subsurface) infrastructure objects, such 
			as long tunnels (for roads, metro, train), pipelines, cables: should 
			these be divided based on the surface parcels (as in Queensland, 
			Australia) or treated as one cadastral object (as in Sweden). In 
			case of subdivision, note that to all parts rights (and parties) 
			should be associated.
 
			- 
			
For the representation (and initial registration) of 
			a 3D cadastral object, is the legal space specified by its own 
			coordinates in a shared reference system (as is the practice for 2D 
			in most countries) or is it specified by referencing existing 
			topographic objects/boundaries (as in the 'British' style of a 
			cadastre). 
 
		
		Note that there can be a difference between the 3D 
		ownership space and the 3D restriction space; e.g. one can be owner up 
		to ±100 m around the earth surface, but only allowed to build from -10 
		to +40 m. Both result in 3D parcels, that is, 3D spatial units with RRRs 
		attached. The ownership spaces (parcels) should not overlap other 
		ownership parcels, but they are allowed to overlap other space; e.g. 
		restriction parcels. 
		Part of the activities of the working group is to make a 
		world-wide inventory of the status of 3D-Cadastres at this moment 
		(November 2010) and the plans/expectations for the near future (2014); 
		see Section 3. This will be done via a repeated questionnaire: one in 
		2010 (status 2010 and plans 2014) and one in 2014 (status 2014 and plans 
		2018). The repeated survey in four years time will be helpful to 
		evaluate the actual progress. Sharing this information improves 
		cooperation and exchange of experiences and supports future developments 
		in different countries and cadastral jurisdictions. A related survey has 
		been conducted among the eight cadastral jurisdictions of Australia (see 
		Section 4). The results and preliminary analysis of the international 
		FIG 3D-cadastres survey is presented in Section 5. Finally, Section 6 
		contains the conclusions and description of future work in the area of 
		3D-Cadastres.
		2. FIG WORKING GROUP ON 3D-CADASTES 
		This section presents the FIG joint commission 3 and 7 
		working group on 3D-Cadastres (2010-2014). In subsection 2.1 the 
		objectives of the working group are formulated. The main research topics 
		of the working group are presented in subsection 2.2, while deliverables 
		and mode of operation are introduced in subsection 2.3. For more 
		information on the FIG working group on 3D-Cadastres, including the 
		overview of relevant 3D cadastre literature and the 35 completed 
		questionnaires, see the website of this working group 
		www.gdmc.nl/3DCadastres.
		2.1 Objectives
		The main objective of the working group is to establish 
		an operational framework for 3D-Cadastres. The operational aspect 
		addresses the following issues: 
		
			- 
			
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); see Figure 1.
			 
 
			- 
			
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.
			
 
		
		
		
		Figure 1. ISO 19152 with 3D spatial units and specializations 
		such as LA_LegalSpaceUtilityNetwork and LA_LegalSpaceBuildingUnit 
		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 and 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). 
		The working group 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. 
		2.2 Research topics
		The working group identified four main research topics: 
		models, Spatial Information Infrastructure (SII, sometimes also called 
		SDI), temporal aspects and usability. These four topics are elaborated 
		on below: 
		
			- 
			
3D-Cadastres and models: It is important to realize 
			that for registration, for storage/validation and for dissemination 
			different models (all based on the shared ISO LADM semantics) may be 
			needed and different types of users are involved. The modelling 
			aspect includes the question of which spatial (esp. height) and 
			temporal information should be used and how different types of users 
			may interact (i.e. produce, archive, edit, analyze, and visualize, 
			edit) with 3D-Cadastre? The 'users' belong to various categories; 
			they range from professionals (which can be further subdivided in 
			notary, real estate brokers, banks, water boards, utility companies, 
			municipalities, cadastral employees, surveyors, etc.) to citizens 
			(with various capabilities of owners/users: from computer 
			illiterates to experienced web surfers/gamers).
 
			- 
			
3D-Cadastres and SII: The registration of legal 
			objects (cadastral parcels and associated rights) and their physical 
			counterparts (e.g. buildings or tunnels) result into two different, 
			but related data sets, which can be very well accessed together via 
			the Spatial Information Infrastructure (SII, sometimes also called 
			SDI). This is already true in 2D, but even more so in 3D. By also 
			showing some physical objects for reference purpose, the location 
			and size of the legal objects will be clearer.
 
			- 
			
3D-Cadastres and time: A 4D parcel is defined as the 
			spatio-temporal unit against which (one or more) unique and 
			homogeneous rights (e.g. ownership right or land use right), 
			responsibilities or restrictions are associated to the whole entity, 
			as included in a Land Administration system. Homogenous means that 
			the same combination of rights equally apply within the whole 4D 
			spatial temporal unit. Unique means that this is the largest 
			spatio-temporal unit for which this is true. Making the unit any 
			larger (in 3D space or time) would result in the combination of 
			rights not being homogenous. Making the unit smaller (in 3D space or 
			time) would result in at least 2 neighbour 4D parcels with the same 
			combinations of rights.
 
			- 
			
3D-Cadastres and usability: The graphic user 
			interface (GUI) is an essential aspect when realizing 3D-Cadastres 
			in practice. This includes investigation of interacting with true 3D 
			cadastral data (specific user interfaces: 3D spatial and perhaps 
			temporal aspects via animations or snapshot sliders). The existing 
			quality of successful and popular user interfaces (such as Google 
			Earth; see Figure 2) will be the starting point with specific 
			attention for working with the main 3D legal object types (related 
			to underground infrastructure and building/apartment complexes). A 
			true 3D cadastral system with functions should be implemented and 
			applied to demonstrate the possibilities in practice based on 3D 
			visualization. How to distribute the 3D cadastral information (3D 
			parcels and associated rights) to the citizens? How to represent and 
			demonstrate the 3D geographic aspect, on paper (with different 
			viewpoints) or on electronic media (interactive tools based on Adobe 
			Flex or Flash)?
 
		
		
		
		Figure 2. 3D visualisation in 
		Google Earth (example Spanish cadastre) 
		2.3 Deliverables and operation
		The working group strives to obtain tangible results 
		that have relevance to the cadastral practice. At the next FIG congress 
		(2014) we want to publish a FIG publication on guidelines to establish 
		3D-Cadastres (a 'Primer on 3D-Cadastres'), addressing legal, 
		institutional and technical issues. In 2011 a second workshop on 
		3D-Cadastres is planned (again in Delft, 10 years after the first 
		workshop). In addition, at the FIG working weeks joint commission 3 and 
		7 sessions on 3D-Cadastes will be organized. Depending on the need and 
		results, additionally a third workshop on 3D-Cadastres could be 
		organized in 2013 or 2014 preferably in conjunction with another FIG 
		meeting (working week, or commission 3/7 annual or congress). Each 
		workshop will be accompanied by a brief progress report. The exchange of 
		ideas and discussions will be facilitated by means of a website on 
		3D-Cadastres. Depending on the issues encountered in our first or second 
		year of operation a survey of user needs (e.g. by means of a 
		questionnaire) might be useful. 
		At the FIG events in the past decade many people have 
		expressed their interested in 3D-Cadastres. In order to push ahead it 
		seems best if the specific themes of 3D-Cadastres (legal, institutional 
		and technical) are lead by a limited number of experts (2-4) who 
		elaborate on their subject. People can then join these groups for 
		discussion and preferably contributions. Task of the chair is to start 
		and encourage these theme-groups, lead the overall issues of working 
		group, and trigger the necessary events. It seems wise to evaluate this 
		way of working after one year. Communication during the projects will be 
		done as much as possible by e-mail and via our dedicated website: 
		www.gdmc.nl/3DCadastres; 
		see Figure 3. At the end of each year a progress report will be 
		available to all members of the interest group and our sponsors in 
		commissions 3 and 7. The Table 1 shows the main events of the working 
		group in time. 
		
		
		Figure 3. Website FIG 3D Cadastres (with participants and their 
		completed questionnaires) 
		Table 1. Timetable with events of 
		the FIG working group on 3D-Cadastres
		
		
		
		
		3. DESIGN OF THE QUESTIONNAIRE 
		
		In this section the design (set-up) of the questionnaire 
		is presented. No matter how much effort one puts in setting-up a 
		questionnaire, the experience shows that the questions are always less 
		clear to the persons/organizations that have to fill in the 
		questionnaires compared to how clear the questions are to the persons 
		that created the questions (even if this was a larger team of persons as 
		in case of the 3D-Cadastres questionnaire). This is caused by the fact 
		that different terms may have slightly different meaning to persons in 
		different countries in the world. This is especially true for more 
		abstract concepts such as 3D Cadastre and 3D parcel. Therefore the first 
		page of the questionnaire contained a few notes (including an informal 
		and a formal definition of a 3D parcel) and suggestions, which should be 
		helpful during the completing the questionnaire. To lower the threshold 
		to complete (and return) the questionnaire it was also explicitly 
		expressed that ‘If a certain question is not relevant or if you have no 
		clue what to respond, do not spend any time on this (and leave the field 
		blank).’ 
		The 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 are associated, as included in a Land Administration 
		system. As this definition is quite abstract, the questions were phrased 
		with more descriptive and real world situations included to explain 
		further. Also two example sets of partial/preliminary answers were 
		included from Queensland, Australia and The Netherlands, to support the 
		questions and to be of help when formulating the answers for other 
		jurisdictions (see Table 2). Despite or due to these preparations during 
		the period of completing of the questionnaire the organizers received 
		two requests for clarification. 
		The questionnaire specifically aims at clarifying the 
		difference between 3D legal space (referred to as 3D parcel) and 3D 
		physical objects. A 3D parcel is a ‘legal object’ describing a part of 
		the space. Often there is a relationship with a real world/physical 
		object, which can also be described in 3D, but this is not invariably 
		the case. The questionnaire was framed to recognise the difference 
		between these two types of objects and that the focus in the context of 
		3D-Cadastres is on 3D parcels (spaces of legal objects). The 
		questionnaire has been prepared by the authors of this paper. The 
		questionnaire was grouped in different thematic blocks. This had no 
		meaning in the sense of priority and it was often possible that a 
		question could belong to multiple blocks. The following nine groups of 
		questions were indentified:
		
			- 
			
General/applicable 3D real-world situations
 
			- 
			
Infrastructure/utility networks 
 
			- 
			
Construction/building units 
 
			- 
			
X/Y Coordinates
 
			- 
			
Z Coordinates/height representation
 
			- 
			
Temporal Issues
 
			- 
			
Rights, Restrictions and Responsibilities
 
			- 
			
DCDB (The Cadastral Database)
 
			- 
			
Plans of Survey (including field sketches) 
 
		
		The first group of questions refers to the applicable 3D 
		real-world situations to be registered by 3D parcels. It also addressed 
		the types of 3D geometries, which are considered to be valid 3D 
		representations for these parcels. The second group of questions refers 
		to the situation where an infrastructure network is considered to be 
		defined within the cadastre. For example in some jurisdictions, an 
		underground network might be privately constructed for the purpose of 
		leasing space in it for other organisations to run cabling. In this 
		case, a network, or part of that network may be considered to be a real 
		estate object. The third group of questions refers to 3D properties that 
		are related to constructions and apartment (condominium) buildings. The 
		individual units are often defined by the actual walls and structure of 
		a building, rather than by metes and bounds. E.g. “unit 5 on level 6 of 
		… building”. The other 6 groups of questions are more or less 
		self-evident. Finally, group 10 the contact details could be provided 
		together with any other issue that was relevant, but not yet addressed 
		by one of the earlier questions.
		Table 2. Sample form the 
		3D-Cadastres questionnaire (section 4. X/Y Coordinates) with example 
		answer from Australia/Queensland and The Netherlands (for the 2010).
		
		The questionnaire was distributed among the member of 
		FIG 3D-Cadastres WG and the members of FIG joint commission 3 and 7. The 
		respondents were asked to complete the two empty columns for their 
		jurisdiction: 2010 (the current status) and 2014 (expectations in 4 
		years time).
		4. AUSTRALIAN PERSPECTIVE 
		The idea for a 3D-Cadastres questionnaire was first 
		‘born’ in Australia. Therefore we start by presenting these results. 
		This questionnaire has been conducted among the eight cadastral 
		jurisdictions of Australia: Queensland, Australian Capital Territory, 
		New South Wales, Northern Territory, South Australia, Tasmania, Victoria 
		and Western Australia (Karki, Thompson, McDougall 2011).. The results 
		from these are summarised and compared to the international situation.
		
		Generally speaking, the states of Australia have 
		different procedures, but attempt to have consistent regulations as far 
		as the public is concerned. This is to ensure that “loop-holes” are not 
		generated by state differences. Differences, when they occur, tend to be 
		in the situations that have come into existence more recently. Thus the 
		first question “Are all 3D parcels constrained to be within one surface 
		(2D) parcel?” has elicited quite different responses, probably because 
		situations such as the subdivision of a surface parcel which has a 3D 
		parcel below it is still a rare occurrence. 
		4.1 Results of the Australian questionnaire 
		The range of responses to the Australian questionnaire 
		was well within the international results (see below), but in summary:
		
			- 
			
All jurisdictions allow 3D parcels to be defined by 
			metes and bounds (without reference to a physical structure), 
 
			- 
			
Alternately all allow parcels to be defined by a 
			physical structure. 
 
			- 
			
All allow a wide range of parcel definitions 
			(possibly including curved surfaces) providing a precise definition 
			is made.
 
			- 
			
Dealings involving 3D parcels are effectively the 
			same as for 2D, but there are some additional restrictions on rights 
			to units in strata.
 
			- 
			
Moving parcels and temporal boundaries are not 
			implemented (although there was confusion in some of the replies)
			
 
		
		4.2 Differences Between Australian and FIG Responses
		
		In the Australian context, all states support a “heaven 
		to centre of earth” approach for rights on most parcels. There are 
		parcels with restricted rights in the form of ownership rights or 
		encumbrance in the strata. Sometimes even the rights or encumbrances in 
		strata are sub-divided, amalgamated or nullified. However, distinction 
		is made between a 2D parcel plan and 3D plan (Volumetric or Building 
		Format). For a Building Format plan which is used to represent strata, 
		the database records a 2D surface parcel outline and the various level 
		details as attributes. For a Volumetric Parcel, easements or leases can 
		be created for the whole parcel or part of the parcel above or below the 
		ground. 
		Below are some of the differences between the Australian 
		and the International context:
		
			- 
			
Constraints to be within the surface 2D parcel: 
			In Australia, 2D parcels are subdivided to reflect 3D ownership, 
			however if the 2D parcels are subsequently subdivided or amalgamated 
			it does not affect the status of the 3D parcel with then may span 
			several 2D parcels. 3D easements or leases may exist on part or the 
			whole of a 2D parcel, may extend to other parcels, may be 
			subdivided, amalgamated or wholly or partly extinguished and may 
			have full or partial overlap with another interest.
			 
 
			- 
			
Empty Spaces or Existing Constructions: 3D 
			rights are permitted as in the case of 3D easements, limited height 
			parcels or Building Format parcels. For example, an apartment block 
			which is demolished with the owners rights being reserved for a 
			replacement on the same level and aspect but not the exact airspace 
			as before. By contrast a parcel (e.g. a marina parcel) may be 
			defined by its location in space without reference to any 
			construction.
			 
 
			- 
			
Boundaries of the 3D parcel: The cadastral 
			survey requirement is quite explicit in that the 3D parcel 
			boundaries to be formed must be measurable or definable 
			mathematically. Volumetric plans and Building format plans deal with 
			strata quite differently. A Volumetric plan uses an absolute height 
			(Reduced Level based on the Australian Height Datum) on the surface 
			while using bearing and distance for the edges, with an isometric 
			drawing provided. A Building Format plan provides an outline of the 
			surface parcel, the building footprint and details of each level 
			while distinguishing between common property and areas of each items 
			such as the main building, patio, balcony, private yards etc.
			 
 
			- 
			
Registration of 3D parcels in the cadastral 
			database: 3D registration is supported by the titling system and 
			3D parcels are registered as either a Volumetric parcel or as a 
			Building Format parcel. In the digital cadastral database, the 
			strata are shown as an attribute and all 3D related information 
			exists in the plan. Building Format plans are not created for every 
			house, but only those requiring strata title. The title database is 
			held separately to the cadastral database and updates are part of a 
			sequential workflow. 3D data is not represented in the viewing tools 
			of the database.
			 
 
			- 
			
Registration of cable and pipeline networks: 
			There seems to be quite a number of ways network parcels are 
			registered in Australia. While some create 3D easements, others 
			subdivide the surface parcels and some do not capture them on plans. 
			2D parcels generally have a minimum size restriction determined by 
			zoning rules but there is no such restriction on the minimum 
			cross-section size of a 3D parcel. 
 
		
		5. PRELIMINARY ANALYSIS OF THE RESPONSES 
		In this section, the preliminary analysis of the survey 
		conducted by the FIG joint commission 3 and 7 working group on 
		3D-Cadastre, 2010-2014 is presented. In total 36 completed 
		questionnaires have been received and they are all available at the 
		working group website (http://www.gdmc.nl/3DCadastres/participants/). 
		All members of the working group responded with exception of the USA 
		(until) today: Argentina, Australia, Austria, Bahrain, Brazil, Canada, 
		China, Croatia, Cyprus, Denmark, Finland, France, Germany, Greece, 
		Hungary, Indonesia, Israel, Italy, Kazakhstan, Kenya, Macedonia, 
		Malaysia, The Netherlands, Nepal, Nigeria, Norway, Poland, Russia, South 
		Korea, Spain, Sweden, Switzerland, Trinidad and Tobago, Turkey, and 
		United Kingdom. Despite all the efforts to make the concepts used in the 
		questionnaire and the questions asked as clear as possible, we received 
		a few requests for clarification by the respondents. This shows the 
		difficulty (and also the importance) to formulate a clear, standardized 
		definition for 3D cadastre and 3D parcels that will fit all 
		jurisdictions. 
		From the completed questionnaires we received, a number 
		of conclusions can be made. The first is that despite all the research 
		in the past year the concepts "3D cadastre” and “3D parcels" are still 
		ambiguous. The completed questionnaires offer therefore in the first 
		place an overview of the very different ways in which systems of land 
		administration deal with the third dimension of rights (or 
		restrictions). Worldwide there are major differences in those systems, 
		mostly the result of cultural and historical differences in background, 
		and these differences influence the organizational, technical and legal 
		aspects of land registration. Because of these differences, a comparison 
		of the responses is not always easy. 
		A general conclusion is that in all jurisdictions, with 
		the exception of Poland and Nepal, 3D parcels can be registered. But in 
		most cases these 3D parcels are (or even limited to) apartment units. 
		That it is not possible to register 3D parcels other than apartment 
		units in a specific land administration does not mean automatically that 
		it is not possible to create rights that are limited in the third 
		dimension. E.g. in the case of South Korea the respondent explicitly 
		indicated that 3D boundaries of rights are possible by civil law, while 
		cadastral regulation does not touch this subject. In the following 
		paragraphs we give an overview of the preliminary analysis of survey 
		results for several aspects. 
		5.1 Are all 3D parcels constrained to be within one 
		surface (2D) parcel? 
		Most respondents replied on question 1.1 of the 
		questionnaire that a 3D parcel must be located within the boundaries of 
		a (2D) parcel. This does not exclude that the building to which the 
		right refers may be situated on several land parcels. Possibly - as in 
		the case of the Netherlands - a legal 3D description of right refers to 
		various 2D land parcels. The responses are not always clear on the 
		question what will happen if the land parcel is subdivided later. In 
		Queensland it is the starting point that the 3D parcel must be within 
		the boundaries of a 2D parcel, but this does not exclude that the 2D 
		parcel may be subdivided later on. After subdivision the original 3D 
		parcel continues to exist and therefore stretches out over two or more 
		land parcels. In Norway and Sweden, 3D properties may be created that 
		extend over or under different 2D parcels. In Finland this possibility 
		is foreseen for the future. 
		5.2 Empty spaces or existing constructions?
		An interesting question is whether registration of 
		rights to empty spaces - such as air spaces or subsurface volumes - is 
		allowed (e.g. to protect an existing panorama) or that the registered 
		right compulsory refers to an existing or future construction. This 
		topic had been addressed by question 1.3. The responses shows that in 
		most countries explicit rules for this do not exist, but also indicated 
		that in general the rights will refer to a construction. Explicitly the 
		possibility of registration of rights for empty spaces are mentioned in 
		Australia and Canada (Quebec), In Finland this is limited to subsurface 
		volumes. By contrast, Norway and Sweden the law expressly exclude this 
		possibility. In these countries there must be a construction, or a 
		building permit issued for future constructions before a 3D property can 
		be registered. In Norway 3D parcels can be nullified in the case 
		construction has not started building the construction that is going to 
		be the 3D property three years after the building permit has been 
		issued. 
		5.3 Boundaries of the 3D parcel 
		Generally the boundaries of 3D parcels refer to walls, 
		ceilings and floors. The respondent for France expressly states that - 
		in the absence of guidelines in this area - virtual boundaries would be 
		possible. With respect to the z-axis (height) it appears that in the 
		vast majority of systems directives on this issue does not exist or the 
		height is not registered. Among the countries that do register the 
		height (in survey plans or in a legal deed) it may be observed that 
		Australia and France make use of an absolute level while in Canada 
		(Quebec) and Sweden reference is made to a height relative to ground 
		level. 
		5.4 Registration of 3D parcels in the cadastral 
		database 
		3D parcels as such do not exist in any cadastral 
		registration. The description of the 3D space will be found in the 
		survey plans or in the legal documents. The standard seems to be that 
		"floorplans" that the boundaries per floor are listed in the title deed 
		or the appropriate public records (Land Book, Land Registry, public 
		records) or survey plans but not in the cadastral database (map). It may 
		be possibly a make a reference to the 3D parcel in the cadastral map in 
		the form of a 2D polygon in a single layer as in the case of Australia, 
		Cyprus (see Figure 4), Croatia (where is spoken of a “2.5D 
		representation”) , Norway and Sweden. 
		
		
		Figure 4. Example from Cyprus: 
		floor plan with 2 cadastral objects at ground, 1st, and 2nd floor 
		(terrace)
		
		In Italy 3D Cadastre in Italy is represented by the 
		Cadastre of Buildings, that exists next to the “Land Cadastre”. This 
		holds an inventory of every building. A very interesting system of 3D 
		registration exists in Spain. Here on the cadastral map a 3D model of 
		the buildings can be shown, including the boundaries of rights inside 
		the buildings. But this is not a 3D representation of the actual height 
		of the units. In fact the representation is based on a standard height 
		of 3 meters from floor-to-floor. Although this is a limitation, this 
		solution does offer a more or less a realistic view of the buildings and 
		property rights within buildings in urban areas, see Figure 5.
		
		Figure 5. 3D visualisation of 
		buildings in the Spanish cadastre (based on a standard floor-to-floor 
		height of 3 meter. 
		5.5 Registration of cable and pipeline networks
		Cable and pipeline networks occupy a special place 
		within the registered 3D objects and rights. These networks often extend 
		over several land parcels and thus have - apart from the height or depth 
		of the structure - a 3D character of their own. In recent years the 
		Netherlands introduced the possibility to register rights to all types 
		of cable and pipeline networks. The networks have a cadastral number of 
		their own. In Switzerland, especially in Geneva networks are included in 
		the cadastral database in a similar way. In the Russian Federation, a 
		network can be registered by the Land Registry, but in practice this is 
		not done. In Kazakhstan, all networks are registered "as legal objects". 
		However the respondent also mentions that underground networks are not 
		registered but only shown on maps. Furthermore, in Canada (Quebec) cable 
		and pipeline networks, rail networks are recorded in public registers 
		(Register or real right of State resource development). It can be 
		requested by the owner that the network is displayed on the cadastral 
		plan, but this rarely happens. The network as such can not be found in 
		the cadastral database, but indirectly through the land parcels in which 
		the network is constructed. 
		
		
		Figure 6. Turkish example ‘3D utility network’: gas (red) and 
		water (blue) map fragment Istanbul reregistered utility data in 
		combination with cadastral map; translation: ‘uzunluk’ = ‘length’, ‘cap’ 
		= ‘diameter’,‘tur’ = ‘pressure’; source (Döner e.a. 2010). 
		In other countries registration of networks does not 
		happen, or is just possible in limited cases, as in Turkey where only 
		high voltage power lines are registered in the cadastral database. 
		Registration of other networks find place at municipal level, and 
		combined with cadastral data, see Figure 6 example from Istanbul, 
		Turkey. A general registration of (underground) networks does not exist 
		in Norway, where telecommunications, water and electricity networks are 
		not registered, but roads and railways are. Some jurisdictions have 
		"utility maps” (Australia, Victoria) or a" utility register " as 
		Croatia. In the latter country is expected that this register will be 
		integrated in the cadastral database in 2014. Also in other countries we 
		see developments towards the cadastral registration of networks, 
		especially in Denmark, Hungary, Israel and Italy. In the latter country 
		this would take place in the context of pilots projects leading to the 
		development of a subsurface cadastre. 
		
		5.6 Developments in the short term
		The purpose of the survey by the FIG Working group was 
		not only to make a world-wide inventory of the status of 3D-Cadastres at 
		this moment (2010/2011), but also to get an insight in the expectations 
		for the near future (2014). However, the planned developments in the 
		field of 3D cadastre for 2014 seem to be very limited. Whether this 
		means that one is satisfied with the existing system of 2D registration, 
		like the respondent for England and Wales expressly stated, remains 
		unclear. The vast majority of respondents did not answer the questions 
		one the expected situation for 2014. The most concrete developments 
		seems to happen in Switzerland, where in 2014 the concept of 3D plots 
		might be introduced, and Denmark, where the respondent mentions an 
		ongoing discussion of 3D parcels should be recorded in the cadastre and 
		a footprint on the cadastral map. Bahrain mentions the future 
		representation of the apartments in the cadastral database. In recent 
		years in Israel there has been much research into the development of a 
		3D cadastre and preparations aimed at legislation and it is hoped that 
		this will result in practical changes.
		6. CONCLUSION AND FUTURE WORK 
		As indicated, the solutions for registration of rights 
		with 3D characteristics are very different. Broadly, one can observe 
		that apartments are registered with drawings in the deed registration. 
		But a true 3D registration in the cadastre does not exist anywhere. Most 
		often it was approached by Spain, although the representation uses a 
		standard height per floor layer. 
		Techniques for 3D data acquisition, management and 
		distribution will be within reach. The next step is to optimally exploit 
		this in order to meet the growing information needs in 3D cadastres, 
		matching specific organizational and legal contexts. The international 
		approach of the FIG working group hopes to make an important 
		contribution to reach this, by the publication of “Primer on 
		3D-Cadastres” providing guidelines for specific contexts and 
		implementations, addressing legal, institutional and technical issues.
		ACKNOWLEDGEMENTS 
		The authors of this paper would like to express their 
		sincere gratitude to the members of the FIG joint commission 3 and 7 
		working group on 3D-Cadastres for their joint efforts to complete the 
		questionnaires: Diego Erba, Ali Aien, Don Grant, Mohsen Kalantari, 
		Gerhard Muggenhuber, Gerhard Navratil, Neeraj Dixit, Ammar Rashid 
		Kashram, Andréa Flávia Tenório Carneiro, Francois Brochu, Louis-André 
		Desbiens, Paul Egesborg, Marc Gervais, Jacynthe Pouliot, Francis Roy, 
		Renzhong Guo, Zhang Ning, Shen Ying, Miodrag Roic, Elikkos Elia, Lars 
		Bodum, Esben Munk Sørensen, Christian Thellufsen, Jani Hokkanen, Arvo 
		Kokkonen, Tarja Myllymäki, Claire Galpin, Hervé Halbout, Markus Seifert, 
		Efi Dimopoulou, Gyula Iván, Andras Osskó, Trias Aditya, S. Subaryono, 
		Yerach Doytsher, Joseph Forrai, Gili Kirschner, Yoav Tal, Bruno Razza, 
		Enrico Rispoli, Fausto Savoldi, Natalya Khairudinova, David Siriba, 
		Gjorgji Gjorgjiev, Vanco Gjorgjiev, Alias Abdul Rahman, Babu Ram 
		Acharya, Benedict van Dam, Chrit Lemmen, Thomas Dabiri, Lars Elsrud, 
		Olav Jenssen, Lars Lobben, Tor Valstad, Jaroslaw Bydlosz, Vladimir 
		Tikhonov, Natalia Vandysheva, Youngho Lee, Amalia Velasco, Jesper 
		Paasch, Jenny Paulsson, Helena Aström Boss, Robert Balanche, Laurent 
		Niggeler, Charisse Griffith-Charles, Cemal Biyik, Osman Demir, Fatih 
		Döner, Gareth Robson, and Carsten Roensdorf. Of course, the authors 
		remain responsible for the correct interpretation and the resulting 
		article.
		REFERENCES 
		
			- 
			
Fatih Döner, Rod Thompson, Jantien Stoter, 
			Christiaan Lemmen, Hendrik Ploeger, Peter van Oosterom and Sisi 
			Zlatanova (2010). 4D cadastres: First analysis of Legal, 
			organizational, and technical impact - With a case study on utility 
			networks. In: Land Use Policy, Volume 27, pp. 1068-1081, 2010. 
 
			- 
			
ISO (2011), ISO 19152. Draft International Standard 
			(DIS), Geographic information — Land administration domain model 
			(LADM), Geneva, Switzerland, 20 January 2011. 
 
			- 
			
P.J.M. van Oosterom, J.E. Stoter, E.M. Fendel (Eds.) 
			(2001); Proceedings International Workshop on 3D Cadastres, 
			Registration of properties in strata, Delft, November 2001, 
			published by FIG (online www.gdmc.nl/3DCadastres/literature) 
 
			- 
			
S. Karki, R.J. Thompson, K McDougall (2011): 
			Analysis of 3D Cadastral situation in Australia, Unpublished Paper, 
			2011
 
		
		BIOGRAPHICAL NOTES 
		Peter van Oosterom obtained an MSc in Technical 
		Computer Science in 1985 from Delft University of Technology, The 
		Netherlands. In 1990 he received a PhD from Leiden University for this 
		thesis ‘Reactive Data Structures for GIS’. From 1985 until 1995 he 
		worked at the TNO-FEL laboratory in The Hague, The Netherlands as a 
		computer scientist. From 1995 until 2000 he was senior information 
		manager at the Dutch Cadastre, were he was involved in the renewal of 
		the Cadastral (Geographic) database. Since 2000, he is professor at the 
		Delft University of Technology (OTB institute) and head of the section 
		‘GIS Technology’. He is the current chair of the FIG joint commission 3 
		and 7 working group on ‘3D-Cadastres’ (2010-2014). 
		Jantien Stoter defended her PhD thesis on 3D 
		Cadastre in 2004, for which she received the prof. J.M. Tienstra 
		research-award. From 2004 till 2009 she worked at the International 
		Institute for Geo-Information Science and Earth Observation, ITC, 
		Enschede, the Netherlands (www.itc.nl). As associate professor at ITC 
		she led the research group in the field of automatic generalization. She 
		was project leader of an EuroSDR project on generalisation from 2005 
		till 2009. Since October 2009, she fulfils a dual position: one as 
		Associate Professor at Section GIS technology at OTB and one as 
		Consultant Product and Process Innovation at the Kadaster. From both 
		employers she is posted to Geonovum. The topics that she works on are 
		3D, information modelling and multi-scale data integration. Since 
		January 2010 she leads the 3D pilot that aims at establishing a 3D 
		reference model in The Netherlands in a collaboration of 55 partners. In 
		November 2010 she received a VIDI grant, which is a prestigious award 
		given by the Netherlands Organisation for Scientific Research (NWO) for 
		excellent senior researchers 
		Hendrik Ploeger studied law at Leiden University 
		and the Free University of Amsterdam, The Netherlands. In 1997 he 
		finished his PhD-thesis on the subject of the right of superficies and 
		the horizontal division of property rights in land. He is associate 
		professor at Delft University of Technology (OTB Research Institute) and 
		holds the endowed chair in land law and land registration at VU 
		University of Amsterdam. His research expertise focuses on land law and 
		land registration, especially from a comparative legal perspective. 
		Rod Thompson has been working in the spatial 
		information field since 1985. He designed and led the implementation of 
		the Queensland Digital Cadastral Data Base, and is now principal advisor 
		in spatial databases. He obtained a PhD at the Delft University of 
		Technology in December 2007. 
		Sudarshan Karki is senior Spatial Information 
		Officer, Cadastral & Geodetic Data (Survey Information Processing Unit), 
		in the Data Management & Acquisition, Spatial Information Group of 
		Department of Environment and Resource Management, Queensland 
		Government, Australia. He completed his professional Masters Degree in 
		Geo-informatics from ITC, The Netherlands in 2003 and is currently doing 
		Master of Spatial Science by Research at the University of Southern 
		Queensland.
		CONTACTS 
		Peter van Oosterom
		Delft University of Technology 
		OTB, Section GIS-technology 
		P.O. Box 5030
		2600 GA Delft
		THE NETHERLANDS
		Tel. +31 15 2786950
		Fax +31 15 2784422 
		E-mail: 
		P.J.M.vanOosterom@tudelft.nl 
		
		website http://www.gdmc.nl  
		Jantien Stoter
		Delft University of Technology + Kadaster
		OTB, Section GIS-technology 
		P.O. Box 5030
		2600 GA Delft
		THE NETHERLANDS
		Tel. +31 15 2781664
		Fax +31 15 2784422 
		E-mail: J.E.Stoter@tudelft.nl 
		
		website http://www.gdmc.nl 
		Hendrik Ploeger
		VU University Amsterdam, Faculty of Law &
		Delft University of Technology
		OTB, Section Geo-Information and Land management
		P.O. Box 5030
		2600 GA Delft
		THE NETHERLANDS
		Tel.: + 31 15 2782557
		Fax: + 31 15 2782745
		Email: 
		h.ploeger@otb.tudelft.nl 
		
		Website: www.juritecture.net
		
		Rod Thompson
		Queensland Government, Department of Environment and Resource Management
		Landcentre,
		Main and Vulture Streets,
		Woolloongabba
		Queensland 4102
		AUSTRALIA
		Tel. +61 7 38963286
		E-mail: Rod.Thompson@qld.gov.au 
		
		Web site: 
		http://www.derm.qld.gov.au/  
		Sudarshan Karki
		Queensland Government, Department of Environment and Resource Management
		Landcentre,
		Cnr Main and Vulture Streets,
		Woolloongabba
		Queensland 4102
		AUSTRALIA
		Tel.: +61 7 389 63190 
		Fax: +61 7 389 15168
		E-mail: 
		Sudarshan.Karki@derm.qld.gov.au  
		Web site: 
		http://www.derm.qld.gov.au/  
		
		
		