Technical Description

Property is created through processing property data sourced from Australia’s States and Territories. Source attributes are mapped and standardised to provide a coherent definition across the jurisdictional supplies, with associated geometry being cleaned and processed to output a topologically consistent layer of Australia’s property boundaries at a national scale.

Each property record has a boundary representing the overall coverage of the single property and a Contributor ID which is the jurisdiction’s reference to the property for land valuation and other property purposes. The Contributor ID can be utilised for searches in the relevant jurisdiction’s land valuation system to provide the indicative value of the property for rating purposes.

Property is updated and released regularly and has integrated relationships with other Geoscape Products. Further information regarding attributes, quality, coverage and product release details are outlined below.

Linkages

Property is integrated with the following Geoscape products:

  • Cadastre

  • G-NAF

  • Buildings

The joins used to link to these products are shown below, with attributes used in the joins described.

_images/property_linkages.png

The property_pid attribute can be used to link to a cadastre_pid in the Cadastre product where a relationship between Property and Cadastre exists. These relationships are represented within the property_cadastre table within the Property product. The three possible relationships between Cadastre and Property are:

  • one cadastral parcel is equal to one property

  • many cadastral parcels make up one property

  • one cadastral parcel contains many properties

Attributes

Contributor ID

The Contributor ID is the property identifier provided by the jurisdiction that is searchable for land valuation and rates purposes. The associated attribute(s) in the jurisdiction source data for each State or Territory are found in the table below.

State

Jurisdiction Value

ACT

TITLE_NUMBER [1]

BLOCK + “/” + SECTION + “/” + DIVISION_CODE [2]

NSW

PROPID

NT

VOLUME_TYP + “/” + VOLUME_NO + “/” + FOLIO_NO

QLD

PROPERTY_ID

SA

ASSNO_TENSEQNO

TAS

PID

VIC

PFI

WA

VPU_VE_NUMBER

Source

The name of the State or Territory that the property data was sourced from. Base Property The Base Property allows for a simple visualisation of property coverage across all States and Territories without overlapping parcels. Only property parcels which are not contained by another property can be part of the base representation.

Area

The area of each property polygon in square meters, calculated from the feature geometry using an equal area projection. The total area in square meters can be calculated by summing property parcels with a common Property PID.

Data Model

digraph G {
fontname="ROBOTO" fontsize="10pt"
node [fontname="ROBOTO" fontsize="8pt"]
edge [fontname="ROBOTO" fontsize="8pt"]
rankdir=LR

graph [pad="0.5", ranksep="1"];

subgraph cluster_property { label="Property"
    graph[style="dashed,rounded"  color="#EA6B66"]

property [shape=plain
label=<<TABLE BGCOLOR="#7EA6E0"
BORDER="1"
CELLBORDER="0"
style="rounded"
CELLSPACING="0"
CELLPADDING="5">

<TR>
<TD  COLSPAN="2">property</TD>
</TR>

<TR>
<TD BGCOLOR="white" >PK</TD>
<TD BGCOLOR="white" ALIGN="LEFT" >property_polygon_pid: varchar (15)  </TD>
</TR>

<TR>
<TD BGCOLOR="white" >FK</TD>
<TD BGCOLOR="white" ALIGN="LEFT" >property_pid: varchar (15) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >contributor_id: varchar (50) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >date_created: date </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >date_modified: date </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >state: varchar (3) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >source: varchar (20) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >base_property: varchar (3) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >area: number (14,2) </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >geometry: Polygon </TD>
</TR>

</TABLE>>];

property_cadastre [shape=plain
label=<<TABLE BGCOLOR="#FFD966"
BORDER="1"
CELLBORDER="0"
style="rounded"
CELLSPACING="0"
CELLPADDING="5">

<TR>
<TD  COLSPAN="2">property_cadastre</TD>
</TR>

<TR>
<TD BGCOLOR="white" >PK</TD>
<TD BGCOLOR="white" ALIGN="LEFT" >property_cadastre_pid: varchar (15)    </TD>
</TR>

<TR>
<TD BGCOLOR="white" ></TD>
<TD BGCOLOR="white" ALIGN="LEFT" >date_created: date </TD>
</TR>

<TR>
<TD BGCOLOR="white" >FK</TD>
<TD BGCOLOR="white" ALIGN="LEFT" >property_pid: varchar (15) </TD>
</TR>

<TR>
<TD BGCOLOR="white" >FK</TD>
<TD BGCOLOR="white" ALIGN="LEFT" >cadastre_pid: varchar (15) </TD>
</TR>

</TABLE>>];

}

property -> property_cadastre [arrowhead=crownoneodot dir=both arrowtail=crownoneodot]

subgraph cluster_legend {
    graph[style="" label="Legend" ]

legend [shape=plain
        label=<<TABLE
            CELLBORDER="0"
            Border="0">
        <TR>
            <TD BGCOLOR="#7EA6E0" BORDER="1">     </TD>
            <TD>Spatial Attribute Table</TD>
        </TR>

        <TR>
            <TD BGCOLOR="#FFD966" BORDER="1">     </TD>
            <TD>Textual Attribute Table</TD>
        </TR>

        </TABLE>>]


       key [shape=plain  label=<<table border="0" cellpadding="1" cellspacing="0" cellborder="0">
      <tr><td port="i1"> Zero or Many </td> </tr>

      </table>>]

    key2 [shape=plain label=<<TABLE border="0" cellpadding="1" cellspacing="0" CELLBORDER="0">
      <tr><td port="i1"> </td></tr>

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    key:i1 -> key2:i1 [arrowhead=crownoneodot]


  }


}

Data Dictionary

property

Attribute

Data Type

Description

Primary Key

Mandatory

10 Character Alias

property_polygon_pid

Character String (15)

Persistent identifier for each property polygon.

Yes

Yes

PR_PLY_PID

property_pid

Character String (15)

Persistent Identifier for the property feature for the life of the property.

No

Yes

PR_PID

contributor_id

Character String (50)

An identifier used to link back to the contributor data where the contributor supplies a persistent identifier.

No

Yes

CNTRB_ID

date_created

Date

The date the record is first introduced to the Geoscape product.

No

Yes

DT_CREATE

date_modified

Date

The latest date that this record has been modified.

No

No

DT_MOD

state

Character String (3)

The abbreviated name of the State or Territory that the property spatially resides within.

No

Yes

STATE

source

Character String (20)

The State or Territory authority that has provided the source data for the property.

No

Yes

SOURCE

base_property

Character String (3)

A ‘Yes’ flag indicates that the parcel is part of the base representation.

No

No

BASE_PROP

area

Number (12,2)

The area in square metres of the polygon.

No

Yes

AREA

geometry

Polygon

The geometry of the polygon.

No

Yes

GEOMETRY

Domain Values

state

Domain Value

Description

ACT

The data is located within the Australian Capital Territory.

NSW

The data is located within the state of New South Wales.

NT

The data is located within the Northern Territory.

OT

The data is located within the Other Territories classification. Other Territories covers the external Australian territories of Cocos (Keeling) Islands, Christmas Island, Jervis Bay and Norfolk Island.

QLD

The data is located within the state of Queensland.

SA

The data is located within the state of South Australia.

TAS

The data is located within the state of Tasmania.

VIC

The data is located within the state of Victoria.

WA

The data is located within the state of Western Australia.

source

Domain Value

Description

ACT

The source data for the record was provided by the Australian Capital Territory Government. Jervis Bay data is sourced from the Australian Capital Territory Government.

NSW

The source data for the record was provided by the New South Wales Government.

NT

The source data for the record was provided by the Northern Territory Government.

OT

The data is located within the Other Territories classification. Other Territories covers the external Australian territories of Cocos (Keeling) Islands, Christmas Island, Jervis Bay and Norfolk Island.

QLD

The source data for the record was provided by the Queensland Government.

SA

The source data for the record was provided by the South Australian Government.

TAS

The source data for the record was provided by the Tasmanian Government.

VIC

The source data for the record was provided by the Victorian Government.

WA

The source data for the record was provided by the Western Australian Government. Cocos (Keeling) Islands and Christmas Island data is sourced from the Western Australian Government.

Geoscape Australia

The data has been created by Geoscape for the purposes of base parcel coverage.

base_property

Domain Value

Description

Yes

The property polygon has been identified as a base property. A base property is not contained by any other property parcel and provides base coverage across each state and territory.

<NULL>

The property parcel has been identified as not being a base property. Property parcels contained by other property parcels will have <NULL> values for this field.

Update Frequency

Property is continuously updated and released with the most up to date data available on a monthly schedule.

Data Quality

Positional Accuracy

Property has been created by combining land valuation/rates information with Cadastre. To achieve a single property representation a union of multiple Cadastre boundaries happens during production. This will preserve the outer boundaries accuracies as supplied by the jurisdiction. Geoscape makes minor changes only where they are required to create valid features described in Property Geometry Validity.

Coordinates Referencing the GDA2020 Datum

Spatial features referencing the GDA2020 datum are produced using a coordinate transformation from the GDA94 datum using the following parameters.

shift_x = 0.06155,
shift_y = -0.01087,
shift_z = -0.04019,
rotate_x = -0.0394924,
rotate_y = -0.0327221,
rotate_z = -0.0328979,
scale_adjust = -0.009994

Property Geometry Validity

Property geometry is validated to ensure polygons are a valid representation and free of self-intersection. Issues being detected and resolved include spikes, bow ties, duplicate vertices, null geometries, multipart geometries, and self-contacts. Minor overlaps are also resolved where a property has a Base Property of ‘Yes’. Overlapping polygons will persist in the product as they can be valid geometries representing the jurisdictions intent.

Polygon orientation conforms to the following specifications:

This means the polygon outer boundary will be counter clockwise and the inner boundary will be clockwise for file formats that support the above standards.

Further Comments

Property has been processed to assure all polygons are stored as single part features to improve capability with a range of software applications. Due to this there is duplication of the Property PID and Contributor ID information.

Extent/Geographic Description

The spatial coverage of Property includes Australia’s land mass and surrounding offshore islands.

The Bounding Box for this data is as follows:

  • North bounding latitude: -8˚

  • South bounding latitude: -45˚

  • East bounding longitude: 155˚

  • West bounding longitude: 112˚

_images/extent_map.png

A detailed description of the coverage for each State and Territory is provided in the table below.

Spatial Reference System

GDA94

Horizontal Datum: The Geocentric Datum of Australia 1994 (GDA94) is the target horizontal datum.

Coordinate System: Geographic Coordinate System Geocentric Datum of Australia 1994 (GDA94).

GDA2020

Horizontal Datum: The Geocentric Datum of Australia 2020 (GDA2020) is the target horizontal datum.

Coordinate System: Geographic Coordinate System Geocentric Datum of Australia 2020 (GDA2020).

Delivery Format

Property is provided at a National and State/Territory level, depending on the file format selected. The data is made available in the File Geodatabase, GeoJSON, ESRI Shapefile and MapInfo TAB formats described below.

Format

National

State/Territory

File Geodatabase

Yes

Yes

GeoJSON

Yes

Yes

ESRI Shapefile

Yes

MapInfo TAB

Yes

File Geodatabase

Format name
File Geodatabase – ESRI™

Specification
This format includes files with the following extensions: *.gdb

Language
English

GeoJSON

Format name
GeoJSON
Specification

This format includes files with the following extensions: *.geojson

Language
English

Note

The GeoJSON specification states that the coordinate reference system for all GeoJSON coordinates is: “a geographic coordinate reference system, using the World Geodetic System 1984 (WGS 84) datum, with longitude and latitude units of decimal degrees” Cadastre will be provided with coordinates using the datum selected for download (GDA94/GDA2020) with longitude and latitude units of decimal degrees.

JSON

Format name
JSON

Specification
This format includes files with the following extensions: *.json

Language
English

ESRI Shapefile

Format name
Shape – ESRI™

Specification
This format includes files with the following extensions: *.shp, *.shx, *.dbf
ESRI Shapefile Technical Description, an ESRI White Paper, July 1998. Follow this link: https://www.esri.com/library/whitepapers/pdfs/shapefile.pdf

Language
English

MapInfo TAB

Format name
TAB – MapInfo Professional™

Specification
This format includes files with the following extensions: *.tab, *.dat, *.id, *.map
The MapInfo TAB format is a popular geospatial vector data format for geographic information systems software. It is developed and regulated by MapInfo as a proprietary format. TAB files support geospatial standards such as Open GIS, the OGC, ISO, W3C and others.

Language
English

Product Versioning

Property versioning is managed through incrementing when there is a change to the product schema or a significant change in data population, these are described further below:

  • A schema change can affect a major or minor increment to the versioning. Additive changes (changes that won’t break customers’ ability to work with the data) will be incremented with a minor version increment, an example is the addition of a new attribute. Removal of attributes or changing the structure of the Property schema will enact a major change to identify that this requires the attention of all customers and partners.

  • Where a significant geography of Australia either has a new population of data for an attribute or is populated from a much higher quality source a minor increment will be applied to the product version.

Therefore, Property versioning will not increment with every data update, published releases will have a name e.g. ‘May 2021’ and will reference a version of the Property product e.g. ‘1.0’.