Geodetic Survey Modernisation activities 2014 ISV Surveying Expo

Geodetic Survey Modernisation activities 2014 ISV Surveying Expo Roger Fraser, Geodetic Survey Office of Surveyor-General Victoria

Outline Geodetic Strategy Consultation Draft New version of SMES Re-adjustment of Victoria’s GDA 94 and AHD survey control networks Progress towards datum modernisation 2

Geodetic Strategy Available as a consultation draft Identifies strategic context, priorities and challenges Focussed on improving positioning accuracy and reliability Guided by 2013 Geodetic Infrastructure Questionnaire results Closing date for feedback is 29 August 3

Geodetic Strategy 4

Geodetic Strategy 5

Geodetic Strategy How important is AHD? Not important 6% Moderate important 24% Very important 70% Very important 6 Moderately important Not important Total responses: 217

Geodetic Strategy 100% Which maintenance/enhancement activities do you feel the Victorian government should continue to invest in 85% Total responses: 177 80% 61% 60% 64% 58% 40% 20% 0% 7 Physical network (e. g. more marks in certain areas, high stability marks, marker posts, etc) Victoria's GNSS CORS infrastructure GNSS CORS real-time positioning The realisation of GDA 94/AHD 71 services (e. g. ongoing upgrades through management and readjustment)

New version of SMES New interface with updated Vic. Map data, Google street view Revised survey control mark categories and symbols Flexible search options and several download format options Online submission of sketch plans and raw survey measurements New geodetic measurements database Rigorous network adjustment system for processing of Victoria’s GDA 94 coordinates and AHD heights Open Web Services to support location based services applications 8

New version of SMES maps. land. vic. gov. au/smes 9

New version of SMES Legend Description SCN Mark. PM with adjusted GDA 94 coordinates, no AHD height SCN Mark. PCM with adjusted GDA 94 coordinates, no AHD height SCN Mark. PM with estimated GDA 94 coordinates, levelled AHD height Non-SCN Mark. PM or PCM with estimated GDA 94 coordinates, no AHD height Non-SCN Mark. PM or PCM with estimated GDA 94 coordinates, estimated AHD height SCN Mark. PM with adjusted GDA 94 coordinates, levelled AHD height SCN Mark. PM with adjusted GDA 94 coordinates, estimated AHD height 10 Defective PM or PCM

maps. land. vic. gov. au/smes 11

maps. land. vic. gov. au/smes 12

maps. land. vic. gov. au/smes 13

maps. land. vic. gov. au/smes 14

maps. land. vic. gov. au/smes 15

2014 Victorian Adjustments Victoria’s GDA 94 and AHD networks re-adjusted. New constraints GDA 94 adjustment fully integrated with GPSnet AHD adjustment aligned with AUSGeoid 09 Rigorous uncertainties Automated process within SMES 16

2014 Victorian GDA 94 Re-adjustment 2 D uncertainties (95%) 18000 15580 16000 Uncertainty 0. 050 0. 025 0. 02 0. 01 14000 12000 Frequency 10435 10000 Percentage 89% 64% 50% 12% 8000 5820 6000 3669 4000 2345 2000 17 1130 952 649 306 181 29 5 0. 200 0. 500 1. 000 More 0 0. 005 0. 010 0. 025 0. 050 0. 075 0. 100 Uncertainty 0. 150

2014 Victorian GDA 94 Re-adjustment Corrections to previous coordinates 18000 15440 16000 13741 14000 Correction 0. 050 0. 025 0. 02 0. 01 Frequency 12000 10000 8000 Percentage 97% 81% 44% 10% 6545 6000 4217 4000 2000 711 153 115 153 17 0. 500 1. 000 2. 500 5. 000 0 18 0. 010 0. 025 0. 050 0. 100 0. 250 Correction

2014 Victorian AHD 71 Re-adjustment 1 D uncertainties (95%) 12000 8000 Frequency Uncertainty 0. 050 0. 025 0. 02 0. 01 9706 10000 7448 Percentage 91% 60% 48% 7% 6000 3577 4000 1912 1562 2000 321 44 57 0 19 0. 005 0. 010 0. 025 0. 050 Uncertainty 0. 075 0. 100 0. 500

GDA 94 - initial establishment 20 GDA 94 constraints

GDA 94 – Present foundation 21 Present constraints

Progress towards datum modernisation Revised constraints (Au. Scope and GNSS CORS) National geodetic networks assembled Reprocessing of all old GNSS data Rigorous adjustment software run on ANU supercomputer Research into best approach for handling deformation and uncertainty Business plan and communication strategy 23

Progress towards datum modernisation National re-adjustment 2015 1994 2000 GDA 94 Established 2010 GDA 94 Adopted 2020 2012 Update Continuously realised Victorian re-adjustment 2014 Divergence of GDA 94 from ITRF (metres) 24 0 0. 4 7 cm per year 1. 1 1. 4 1. 8

ITRF velocity model 25

Progress towards datum modernisation New datum based on 2020 epoch (1. 8 m difference) Continuously realised frame, and a static realisation New tools and procedures Stakeholder consultations being run to identify issues, implications and best transition approach ICSM PCG and OSGV to provide leadership and assistance to surveying and spatial information stakeholders 26

Geodetic Survey Modernisation activities 2014 ISV Surveying Expo Roger Fraser, Geodetic Survey Office of Surveyor-General Victoria