NSW DCDB July 2010

BOB DAVIS, Team Leader DCDB Update

BILL MILLER, Team Leader DCDB Upgrade

BACKGROUNDInitial capture commenced 1989 using Genamap software and was completed in1993. Best available datawas used :

• CMA cadastral maps drawn from old parish maps and hand plotted plans ranging in scale from 1:2000 to 1:100 000

• Crown town and village maps• Digital data sourced from Sydney Water, Hunter

District Water Board and Shoalhaven City Council• Manual update and digital capture of hard copy maps

was undertaken by a combination of private contractors and in house staff

• LPI Bathurst staff provided quality control of contractor captured data

DCDB Update

CONTENT

Fabric Layer

The DCDB currently contains 4,135,300 “legal”fabric parcels

• 3,055,200 lot parcels • 44,500 unidentified parcels• 1,017,600 road parcels • 18,000 water feature parcels

DCDB Update

CONTENT

Corridor Layers

The DCDB currently contains 902,000 corridor feature parcels

• 875,900 road corridors• 5,100 railway corridors• 21,000 water feature corridors

DCDB Update

CONTENT Administrative LayersThe DCDB contains 14 administrative layers

• County• Federal Electoral Division• Land District• Lands Office• Local Aboriginal Land Council• Local Government Area• Mines Subsidence District• Miscellaneous Reserves• NPWS Reserve• Parish• Rural Land Protection District• State Electoral District• State Forest• Suburb

DCDB Update

UPDATE SOURCES

• New plan registrations at LPI Sydney• Amendments from Crown Lands Division• Gazette notices, legislation and notification• New and amended data from external

agencies• Corrections to DCDB identified both internally

and by external agencies

DCDB Update

ACTIVITY BY UPDATE TYPE

• Plan updates – 67% (43% subdivision updates, 57% non subdivision, e.g. compilation, strata)

• Ad Hoc updates, corrections and/or modification of existing data - 16%

• Corridor updates - 5%• Administrative boundary updates

gazetted/notified or by legislation - 3%• Miscellaneous updates – 9%

DCDB Update

ACTIVITY BY JOB AND FEATURE COUNT • Average 26,000 jobs processed per year• Average 30,000 lot features added per year,

with 147,000 lot features being modified• Average 68,000 road, railway and water

features added/modified per year• Average 38,000 road centrelines

added/modified• Average 420,000 plan lines added/modified per

year• Average 740,000 “cadpoints” added/modified

per year

DCDB Update

RESOURCES• ARC ESRI GIS software which was adopted in

December 2004 is used to update the DCDB• ARC provides a job management system (JTX)

which enables all jobs to be tracked by operator and job stage

• Access to title data and plan images is provided through the Department’s “SIX” website

• Imagery and/or topographic data is also imported where required

• The process is managed by a Team Leader and 2 Supervisors, with 20 operators undertaking jobs allocated by LGA

DCDB Update

ACCURACY• Except where data has been upgraded the base data

accuracy is derived from the accuracy of the original source documents, e.g . + or - 2 metres from 1:4000 maps, + or - 12.5 metres for 1:25000 maps etc

• Generalisation caused by original map scale results in some boundary steps and bends being omitted from the data

• Digital data used in original capture carries no accuracy as supplying organisations could not provide metadata

• Unless the area has been upgraded, no accuracy metadata is stored against points or lines, rather the accuracy of the base data is referred to when needed

DCDB Update

UPDATE PROCESS• Plans registered at LPI Sydney are scanned and

incorporated into job packets that are placed on the job queue that are accessed by update operators using JTX.

• Where jobs are corrections or miscellaneous jobs the jobs are created by the operator.

• Bearing and distance data is captured for “Survey” type jobs and stored for later access in the upgrade process.

• The captured plan data is input using a ”fit to fabric” process except where gross errors outside of expected base data accuracy are found, when “Ad Hoc” updates are carried out to fix such problems

DCDB Update

UPDATE PROCESS(Continued)

• The system imposes strict checks to ensure our cadastral business rules are adhered to in the “BUILD” stage and that topology is maintained in the “QA VALIDATE” stage

• Completed jobs are then incorporated into the DCDB Maintenance data set in the “POST” stage

• Data from the maintenance data base is posted to the delivery data base for distribution to clients

DCDB Update

UPDATE PROCESS OVERVIEW

DCDB Update

DCDB USE BY LGA

DCDB Data Supply

INCREMENTAL UPDATE SUPPLY

DCDB Data Supply

FREQUENCY OF UPDATE SUPPLY

DCDB Data Supply

DCDB Upgrade

WHY UPGRADE

• Conflicting accuracy with other datasets

• Availability of a range of accurate imagery

• Accurate GPS for positioning assets

• Increased use of GIS applications

DCDB Upgrade

WHY A SINGLE CADASTRE

• Eliminate duplication

• Single source of reference

• Consistent approach to upgrade

• Incremental electronic updates

• More than 150 potential clients

DCDB Upgrade

UPGRADE PROGRAM

• LGA Based

• Agency enters into a MOU

• Agency commits to a Single Cadastre

• Compelling or strategic reasons - internal and external

• Available survey control, accurate plans and connections

CURRENT PROGRAM• Sydney Metropolitan

– Sydney Water Completed 2007– Spatial comparison of approximately 1.35 million polygons– 400,000 polygons upgraded to SWC position

• Regional NSW– Cities– Towns and villages– 200,000 polygons upgraded

• Rural NSW– Test 3,500 polygons

DCDB Upgrade

TARGET ACCURACY• Sydney Water AOI within 0.2 of SW position

• Metro Areas– 0.5 metres is achievable with adequate survey control and plans– 0.3 is achievable with optimum survey control and plans

• Urban Areas – 0.5 metres is achievable with adequate survey control and plans– 0.3 is achievable with optimum survey control and plans

• Rural Areas – depends on control source– LPMA developing improved processes

DCDB Upgrade

DCDB Survey Plan Content

DP’s in DCDB(Excluding Departmentals) 549958

49.4%

Departmentals 98927 9.9%Portion PlansDP 750001 to 757523 363833 32.7%Town Portions DP 757523 to 759144 100895 9.0%

Total1,113,61

3 100%DCDB Upgrade

Cadastral Upgrade

Type of Survey Plans in DCDB

549958, 49%

98927, 9%

363833, 33%

100895, 9% DP's in DCDB (ExcludingDepartmentals)Departmentals

Portion Plans

Town Portions

12.7% has Control

1.7% full Geometry

All 750,000’s DPsBathurst Regional LGA

UPGRADE METHOD

• Complete B&D capture

• Cadastral traverses

• Conflation

DCDB Upgrade

Old Position

Upgraded Position

Cadastral Upgrade

COMPLETE B&D CAPTURE

Cadastral Upgrade

Cadastral Upgrade

CADASTRAL TRAVERSE

Conflation

Cadastral Upgrade

CONFLATION

Cadastral Upgrade

IRRIGULAR SHIFTS

DCDB Upgrade

UPGRADE RESOURCES• ARC ESRI GIS – capture and manage data

• ACRES - capture adjust and integrate data

• Conflation - move DCDB to another target dataset

• Upgrade Manager (CE) capture and adjust small areas

• Team Leader and two Supervisors, with 10 operators

DCDB Upgrade

Survey Measurements + LSA1890 Survey Plan

Survey Measurements + LSA1995 Survey Plan

Survey Measurements + LSA2008 Survey Plan

CADASTRAL FABRICContractor, Council, LPMA

Least Squares Adjustment of 1000s of plans in one

adjustment

DCDBStatic Shape

2010 Plan Update New Title

Fit to Fabric

Fit DCDB fabric to PlanReadjust DCDB every

update

Alternate Plan Update

New Title

Observe how measurements change throughout the process. How important is it?

MILLIMETRE MADNESS

GapsOverlaps

DCDB

Adjustment Job

DCDB Upgrade

Buffer Polygons

DCDB

Outside Boundary Locked Down

Flexible Inside

Boundary

DCDB Upgrade

INTEGRATING ACCURATE DATA

DCDB Upgrade

MOVING ASSETS• Pipes, wires, planning etc

• Shift vectors provided by LPMA

• Software solutions

• LPI Support

• Contractor services

DCDB Upgrade

METADATA

DCDB Upgrade

PARTNERING TO ACCELERATE THE UPGRADE PROCESS

• LPMA will provide free of charge:– Imagery– Access to SCIMS– Copies of plans– Access to CORS for an agreed period– Consultation with LPMA staff on upgrade strategies

• Council might provide– Plan geometry– Upgraded cadastre– Survey – Imagery– Reconnaissance

DCDB Upgrade

Cadastral Upgrade