digital cadastral databases

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digital cadastral databases
Wolfgang Effenberg
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cadastral map
land developer
cadastral system
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cadastral map description

• topographic map
• graphical cadastral map
• survey accurate cadastral map
• legal cadastral map
• coordinated cadastre ?

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UK - Scotland
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Austria
original 1820-1824digital map 1994
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Austria
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Canberra
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Victoria
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observations of spatial cadastres

• tradition of cadastral maps
• public access
• accuracy of cadastral maps
• multi purpose cadastral maps
• spatial data infrastructure
• differing institutional roles
• common digital issues

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cadastral data components

• register of parcel related information
• register of control points
• individual surveys relating to parcel boundaries
• cadastral map (DCDB)
• vs FIG statement - textual and spatial

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spatial cadastres

• England - no cadastral map
• large scale topographic maps are used to map the
  general parcel boundary if required

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spatial cadastres

• England - no cadastral map
• Australia -Vic NSW-graphical cadastre
• that maps the entire cadastral fabric to
  prescribed accuracies

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spatial cadastres

• England - no cadastral map
• Australia -Vic NSW-graphical cadastre
• Denmark - controlled graphical cadastre
• increasingly utilising survey accurate
  measurements tied to national control

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spatial cadastres

• England - no cadastral map
• Australia -Vic NSW-graphical cadastre
• Denmark - controlled graphical cadastre
• Australia (ACT) - survey accurate cadastre
• not part of the legal land titling or land
  register documentation.

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spatial cadastres

• England - no cadastral map
• Australia -Vic NSW-graphical cadastre
• Denmark - controlled graphical cadastre
• Australia (ACT) - survey accurate cadastre
• Austria - legal survey accurate cadastre
• the digital cadastral map is the legal
  representation of the parcel boundary.

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cadastral content - spatial

• parcel boundaries
• easements or right of ways
• property boundaries
• building footprints
• land use boundaries
• occupation boundaries
• cadastral administration boundaries
• general administration boundaries

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cadastral content - aspatial

• parcel identifer
• survey identifer
• property identifier
• street names
• street address
• accuracy indication

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Uses of spatial cadastral data

• index
• land market
• base map
• councils and utilities
• display
• census data
• analysis

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infrastructure? multipurpose?

• multipurpose cadastre
• to service the widest range of users and
  innovative uses outside it traditional land
  tenure role
• infrastructure component
• to facilitate the integration of data and support
  spatial information business systems critical to
  sustainable economic, social and land development

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spatial cadastral system
cadastral map
land developer
?
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maintenance - update and upgrade

• distribution of changes
• changes to spatial cadastre

maintain digital cadastral map map custodian
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spatial cadastral updates

• recording all new legal subdivisions
• ensuring map completeness including recognised
  backlog or holes in the map
• inclusion of a proposed or planning data or layer
  to secure planning spatial cadastral.

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spatial cadastral upgrades

• increase in spatial accuracy of any part of the
  cadastre
• the inclusion of survey control and measurements
• alignment of the cadastre with topographic
  features
• changes in spatial data models to introduce (or
  delete) entities
• generation of topological spatial structures
• inclusion of a historical layer to allow
  verification of new parcel creation
• unique feature identification for all spatial
  entities.

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spatial cadastral maintenance

• encompasses both update and upgrade
• where the update and the upgrade may occur
  simultaneously
• controlled update

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spatial cadastral system
cadastral map
land developer
Australia
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institutional issues - DCDB creation

• surveyor general
• crown land
• topographic mapping
• surveyors
• land titles offices
• freehold land
• surveying and mapping
• water authorities

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Australian state DCDBs

• digistised from best available paper maps
• urban, rural and metro
• varying accuracy
• sourced from different bodies
• different data emphasis
• post title product
• business focus

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DCDB maintenance

• incremental flow of spatial data
• different institutional issues
• differing business requirements
• cost recovery
• infrastructure role

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analogue spatial data system
customers
state digital cadastre

• organisations

land titles office
local government
utilities
surveyor
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data flow diagram for spatial cadastral data
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transfer of data - network
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cadastral update - issues solutions

• currency
• planning data
• crown lands
• back log
• incremental updates
• shifting cadastre
• pricing

• proposed layer
• digital lodgment
• incremental updates
• unique feature identification (ufi)
• version control
• mirror sites
• pricing review

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cadastral upgrade - issues solutions

• accuracy
• loss of accurate data
• topographic alignment
• data model
• topology
• parcel/property
• building footprint
• aspatial attributes
• street addressing
• standards

• cooperative ventures
• institutional reform
• organisational integration
• new technology
• topology
• point level ufi
• parcel and property
• seamless database
• attributes review

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digital environment
Surveyor/ Developer
Electricity
Gas
Telecoms
Digital Spatial Planning
Water
LocalCouncils
Digital Lodgement
E-Commerce
Incremental updates
Land TitlesOffice
State DCDB
Viewing Internet
Searching Delivery
Spatial Data Customers
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observations of Australian DCDBs

• Australia wide DCDB
• graphical cadastre
• high GIS focus
• state by state solution
• meta data
• accuracy upgrade
• incremental updates

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