© Geodata Australia CADASTRAL UPGRADE PROJECTS for LOCAL GOVERNMENT A Possible Upgrade Path

© Geodata Australia Geodata Process The Geodata process using software developed by Michael Elfick with Mike Fletcher and Mimaka Pty Ltd and now represented by Geodata allows the creation of a coordinated digital cadastral database from original survey data thus preserving the mathematical integrity of the original survey observations

© Geodata Australia It is Unique  The traditional method for surveying land is to measure a precise control network and then use this to fix the position of the land parcel.  Geodata has followed the Elfick approach and adopted the inverse of this concept in that the land parcels are captured, joined and assembled and then analyzed to determine the amount and location of the control required.

© Geodata Australia The Background  The process was developed as a result of investigations and a trial conducted by the NSW Lands Department together with the Association of Consulting Surveyors and University of Newcastle to determine whether a reasonable and cost effective alternative existed to creating a DCDB from digitised topographical maps.  The decision was taken following the investigations to implement proposals to digitise topographical maps.  Michael Elfick continued developing his cadastral software – CADP in the belief that it presented a better Cadastral Database

© Geodata Australia The Background  CADP as the program was then known has been used to create and manage the NCDB in the ACT and the NT (NCDB is used to differentiate between the spatially accurate Geodata cadastre from the DCDB derived from digitised topographical maps.  CADP has also been used in NZ, USA and The Philippines for cadastral management projects and has been successfully trialed and demonstrated in a number of Australian jurisdictions CADP has been licensed to Geodata and renamed GeoCadastre

© Geodata Australia The ESRI Connection  Geodata and ESRI have worked collaboratively to incorporate GeoCadastre into ArcMap as an extension to Survey Analyst which will be released to international markets circa Q1 2007, in ArcGIS 9.2  The Survey Analyst 9.2 will allow the storage of cadastral data in a geodatabase without any loss of mathematical integrity to the survey data.  SurveyXML™ has been jointly developed with ESRI as an interchange format to transport cadastral data to the geodatabase.

© Geodata Australia CAD data Text and Paper Documents - Data automation and maintenance - GIS analysis - Enterprise mapping requirements - Land records - Surveys Information System - Measurement-based Cadastre Maps, Plats Field Books Geodatabase Applications GIS data Imagery Survey Data (measurements) Field Measurements Other survey and engineering file formats Other survey and engineering file formats The ESRI Model for Application of GeoCadastre within Survey Analyst

© Geodata Australia Step by Step Geodata Approach to Cadastral Upgrade Step 1 – Collate source Deposited Plans and machine readable survey data Step 2 – Capture and convert source data – data entry from survey plans and or electronic files Step 3 – Identify irregularities and misclose Step 4 – Rectify errors Step 5 – Incorporate base cadastre with client GIS systems Step 6 – Move Asset Layers to the Accurate Cadastre Step 7 – Consult on maintenance of cadastral dataset

© Geodata Australia Data Entry Parcels Joined & Assembled Fabric Adjusted Data Delivery to Clients Built Environment GeoCadastre Process Survey Plans NCDBNCDB Survey Record Web Delivery Possible

© Geodata Australia Conversion Stage 1 - Parcel Data Entry  Keyboard operation  Screen will display the lines as they are entered  Enter bearings distances and areas – in the plan units of measurement : calculation of close and accuracy applied by the software  Supervisor would check errors on regular basis and rectify as needed

© Geodata Australia Conversion Stage 1 - Parcel Data Entry As parcel data is entered from the keyboard the drawing appears on screen

© Geodata Australia Conversion Stage 2 - Parcel Joining  Achieved by mouse operation  Parcels joined together by clicking on matching points  Operator checks rotation and scale precision and notes errors for supervisor rectification

© Geodata Australia Conversion Stage 2 - Parcel Joining Joining – Check scale, then type ‘y’. Common points on the parcel and the existing fabric are selected Parcel to be joined to the fabric is selected and common points of connection are selected

© Geodata Australia Common Points Selected & Parcel is Added into the Cadastral Fabric The joined parcel is added to the fabric and now appears in the parcel explorer window as joined

© Geodata Australia Conversion Stage 3 Adjustment & Assembly  Select known co-ordinate control points to adjust an area  Choose geodetic system, zone and acceptable tolerance for the adjustment based on precision of survey plans  Run the co-ordinate adjustment process

© Geodata Australia Conversion Stage 3 – Co-ordinate Adjustment Tolerances set Listing file location nominated Adjustment summary detailed

© Geodata Australia Cadastre – Display Parameters Easements Roads and Parcel Lines are shown in different colours and various display parameters can be turned on and off

© Geodata Australia Plan Shaded to Show Plan Accuracies

© Geodata Australia The Outcome  A complete parcel network;  A correct cadastral dataset;  Co-ordinate precision  The cadastral base layer for GIS

© Geodata Australia Zoom Window of DCDB (Blue) Overlaid on NCDB (Red)

© Geodata Australia Differences between NCDB and DCDB Gross error here of 101.6m but typically in this dataset the errors are circa 8 metres

© Geodata Australia Benefits of an NCDB 1.Complete, correct and precise position based cadastre 2.One common cadastre for all users 3.Elimination of duplication 4.Reduced delays for update 5.Provisional layer for planning purposes is possible 6.Unification of GIS with GPS 7.Interchangeable datasets between users 8.Reduction in labour intensive GIS conversions

© Geodata Australia Alternative – Gradual Upgrade  The cost of re-building a cadastre to NCDB standards from scratch is often greater than Councils are prepared and able to meet.  Geodata is able to assist in the alternative process of gradual upgrade to numeric standards

© Geodata Australia Progressive Upgrade  Using the existing DCDB as a base, accurate cadastral data can be prepared using GeoCadastre and inserted into the DCDB.  The DCDB for an area is first brought into GeoCadastre through GeoSurvey.  The following is the Gloucester DCDB on which Geodata is currently working

© Geodata Australia Area 5 within the DCDB

© Geodata Australia Progressive Upgrade  Area 5 comprises some parcels for which reasonable plans are available but the balance is an area comprising old system titles where reasonable survey data is not immediately available  Area 5 is exported from MapInfo (the format the DCDB was received in) but could as easily done from ArcMap for import to GeoSurvey

© Geodata Australia Area 5 Export from MapInfo (or ESRI ArcMap)

© Geodata Australia Converting Strings to Parcels in GeoSurvey Inversing the DCDB parcels

© Geodata Australia Area 5 in GeoCadastre The DCDB Converted to GeoCadastre format

© Geodata Australia Adjustment of Area 5 Control is applied and the cadastre adjusted without any attempt to improve accuracy

© Geodata Australia Accurate data to be appended Cadastral data recorded in GeoCadast re from survey plans

© Geodata Australia Unjoining parcels ready for appending Parcels comprising the accurate data are unjoined from the DCDB dataset

© Geodata Australia Appending accurate data The survey accurate GeoCadast re dataset is appended and joined to the DCDB

© Geodata Australia Accurate data joined with digitised DCDB

© Geodata Australia Whole Dataset Shaded to Show Relative Accuracy (Age of Plans) Weighting of data in the adjustment process is reflected in age of plans. Digitized DCDB is Orange

© Geodata Australia Progressive Upgrade  It can be seen from the last group of slides how a progressive update of cadastral data can be achieved using Geodata software and process  The process can be dictated and controlled by Council to it’s own timetable and requirements  Relatively unskilled (in Survey of GIS disciplines) personnel can be used for this process

© Geodata Australia Progressive Upgrade  To enable a Council to proceed immediately with a progressive update of it’s cadastre it would need to purchase at least one seat each of GeoCadastre and GeoSurvey  The cost of GeoCadastre and GeoSurvey is $3,750 each per seat plus annual maintenance (optional) of $500 each which carries with it free technical support and upgrades.  Discounts are available for multiple purchases.

© Geodata Australia Progressive Upgrade  Geodata is also able to offer consultancy services on cadastral upgrade and management  Consultancy services are available from Geodata at negotiated per diem rates

© Geodata Australia Inquiries:  Roger Lee Address: P.O. Box 574 East Maitland N.S.W   Tel:  Fax:  Mobile: