D E V E L O P E D B Y G E O D A T A A U S T R A L I A P T Y L T D
Survey Database Management Tool with
Co-ordinated GIS Cadastral Outcomes
GeoCadastre®, utilised by ESRI under Licence from Geodata Australia Pty. Ltd., since 2007, is a unique, survey-based process developed by us to create and manage a numerical cadastral database (NCDB) which can provide spatial precision to GIS cadastral layers. The process has been separately licensed as the cadastral management engine within the ESRI database environment where it has been enhanced with considerable GIS functionality. GeoCadastre® has retained its basic functionality to minimise complexity with product development focused on survey data examination and validation.
Using survey rules and rigour (data verification) when applicable, the GeoCadastre® (GC) process replicates and automates the workflows and intuitive decisions made by surveyors to define cadastral boundaries. Existing survey cogo outcomes identify the local relationship between adjoining surveys whereas the GC solution can spatially manage a database of thousands of surveys.
The process accommodates all types of survey data (traverse, GPS, digitised maps etc.) and good and bad spatial accuracy through the weighting functionality. The data structure provides future management efficiencies and survey rigour to generate the highest accuracies when required or ease of management when not. Importantly, the spatial precision is stored as an attribute of a parcel.
A rigorous “least squares” technique to weight the accuracy of the survey measurement data and adjust the parcel network to geodetic control points;
Generates “survey accurate” coordinates as attributes of points in the parcel network;
Links the cadastre to GPS;
Facilitates the management of a dynamic geodetic reference system;
Creates and exports the cadastral dataset in file structures suitable for object oriented databases;
Provides the framework for complete digital workflows including electronic lodgement of XML survey plan files, automated plan examination and cadastral database updating and upgrading.
GeoCadastre® Software Characteristics:
Uses a single executable file which simplifies installation (no Registry entries or other intrusive procedures are necessary to make the software work);
Creates a co-ordinated Numerical Cadastre from Survey Plans;
The Numerical Cadastral Database (NCDB) is defined as the complete and precise parcel network derived from original survey plans, preserving their existing mathematical integrity (good and bad) and co-ordinated to the geodetic grid of choice);
Preserves all historical plan details (when they are recorded during data entry);
Manages all overlapping spatial entities.
CREATING THE CADASTRAL FABRIC
The GeoCadastre® process facilitates the input of survey measurement data from original title plans or co-ordinates. The cadastral outcomes are weighted to reflect the integrity of those original survey observations. The process builds a cadastral database model equivalent in spatial precision to the survey data entered. Electronic survey data can also be imported or existing co-ordinated cadastral databases can be migrated as a means to create a starting cadastral fabric. More accurate recent survey data can then be added and the process of building an accurate cadastre is commenced.
The survey based GeoCadastre® process provides a more rigorous solution than the mapping based GIS database creation solutions used in the past. The outcomes of the GeoCadastre® process are database accuracy and greater database management efficiencies.
The GeoCadastre® development team has spent considerable time over the last few years developing digital lodgement and plan examination tools for New South Wales and the Northern Territory. Many of those tools have now been incorporated into the COTS GeoCadastre® solution.
NOTE: In NSW, the ICSM LandXML survey plan files are converted to the COTS.acs/ESRI CEXML data structure to be accessed by the NSW LPI examination tools developed in-house.
The GeoPlan™ tool, referred to and described on the next page, is used for that purpose. In the NT, CEXML survey plan files and survey databases are used as a simplified lodgement and examination data structure.