The SCDB Landgate Western Australia Lou Teeuwissen Manager SCDB DCDB National Workshop Sydney
Overview of Presentation Brief history of the SCDB SCDB advancements Database architecture Daily maintenance Current survey process SCDB element attributes Spatial upgrade program System features Data access Issues 2
History of the SCDB Capture completed in 1990 Digitised from the agency’s 5,500 working plans Plans of various scales ranging from 1:2000 up to 1:500,000 Point coordinate accuracy achieved was no better than 1 mm at map scale (eg to 2 metres at 1:2000 and 250 metres at 1:250,000) 3
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Advancements in the development of the SCDB Spatial upgrade 93% completed to date Entire coastline updated with data sourced from within Landgate All administrative area’s captured Lodged layer introduced in 1995 Development of shared line usages Ability to show spatial interests (e.g. easements, tree plantations, carbon covenants) 2002 Eradication of road “voids” approx 85% complete Introduction of automatic survey integration 2005 Connectivity between SmartPlan and SmartRegister
Database Architecture
Daily maintenance Landgate undertakes to maintain, improve and enhance the SCDB for: –Currency –Accuracy –Completeness In order to: –provide an accurate cadastral framework for use by both external and external stakeholders –provide an accurate framework for initiatives such as SLIP, MapViewer, Property Finder etc –support it’s statutory responsibilities for registration and valuation 7
Daily maintenance.. cont Placement of new surveys into the lodged layer Integration of approved surveys Spatial upgrade Tenure maintenance Ad hoc error corrections Allocation of lot numbers to support digital crown title creation Capture of infrastructure easements Road polygon capture Coastline and inland water updates Administrative areas changes 8
Current survey process SMARTPLAN SMART REGISTER PLANNING APPROVAL SMARTPLAN SMART REGISTER PLAN LODGED Auto placement into Lodged Layer Mathematical close report Lots created *Title documents lodged PLAN AUDITED DRAFT TITLES CREATED PLAN PLACED “IN ORDER FOR DEALINGS” TITLES CREATED Manual process Certified Correct Title documents examined Plans sent, signed and returned electronically PLAN APPROVED AUTOMATICALLY INTEGRATED SMARTPLAN
Some facts about the SCDB Contains over 4.2 million cadastral points and 1.6 million polygon Elements (points, lines, angles, polygons) have unique numeric identifiers Elements are attributed with derivation method Elements have time stamps for create, modify and retire Lines can have multiple usages Accuracy indicators provided 10
Element attributes Points –Least Square Adjusted –Traverse Adjusted –Keyed in –Precal –Digitised –Transformed –Graphical Construct Lines and angles - Measured - Calculated - Derived - Described - Approximate
Point Identification In Digitised Area Coordinate values Coordinate method - Digitised Point Accuracy metres based on map scale
Point Identification In Spatially Upgraded Area Coordinate values Coordinate method - Least Square Adjusted Point Accuracy metres circular error
Line Identification In Spatially Upgraded Area Distance will be the observed distance Derivation is measured Accuracy is 1:4000
Multiple line usages
Multiple line usages…cont
Spatial Upgrade Currently undertaken by Landgate resources under recurrent funds Some has been completed externally and paid for out of capital funds Some has been completed internally and externally funded First pass due for completion in 2014 A second pass is planned to take advantage of any additional control and to adjust new data introduced into previously spatially upgraded areas; already occurring to a limited extent 17
Spatial Upgrade…cont Accuracies achieved are: Metro +/- 0.25m Rural +/- 2m Pastoral +/- 10m Special Survey Areas Accuracy +/ m to +/ m Supported by a local control network tied into the geodetic network 18
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System features
Search methods
Browse Survey screen
Survey screen
Graphic screen
Map types - Derivation
Map types – Survey Index Plan
Data Access Methods 28 My Landgate – Access to SCDB and all attribute information through Map Viewer. Order Form – Access to the Cadastre via dissemination. Access is granted through single orders or annual licensing agreements. SLIP – Access via a web service to the data. Cadastral data can be queried and downloaded as required.
Issues Misinterpretation of data by users –Attribute information not properly understood –Land area’s being misused Referential topology –Agencies looking to Landgate to take the lead –Some agencies already taking steps to resolve their problems Data quality System stability
Questions? 30