As communicated previously, the final stage of the Landgate GDA2020 implementation project will deliver the full implementation of GDA2020 into SLIP, including data storage, web services and maps. This means SLIP subscription services and all other SLIP services will change to GDA2020 as the default datum but will support transformation on-the-fly to GDA94 and WGS84. The GDA2020 implementation is scheduled for 24 July 2022.
- Testing has been completed:
A thorough testing phase involving both external and Landgate SLIP users has now been completed to ensure that the proposed solution will work as intended. This testing phase validated that in most cases there will be no impact to users and services can continue to be used as they currently are, without any change required. There will be no need to repoint any existing connections, the change will simply enable those ready to move to GDA2020 to do so. Users of any of the SLIP web maps LandInfo WA, Locate, Map of Bushfire Prone Areas and WA Marine Map will not be impacted.
Please see the high-level overview below:
Current State
Future State
- Results of testing:
One limitation identified during testing relates to the transformation on-the-fly back to WGS84 and GDA94, in that the Esri software does not allow for the intended transformation to occur outside of the NTv2 grid (this impacts offshore areas including Cocos Keeling and Christmas Islands) Unfortunately, this means that when working with web services in these legacy datums anything outside of the NTv2 grid will remain in the GDA2020 geometry and a misalignment of approx. 1.8m will occur. We recommend that when accuracy is required in these areas the SLIP data downloads extracts are used.
As well as this limitation, the testing did identify two potential use cases where users may have to make changes in preparation for the GDA2020 implementation. These are:
- FME users extracting directly from the webservices – a solution has been identified please see this link for more details.
- TechnologyOne SLIP Downloader users – a solution has been identified and will be communicated via TechnologyOne.
While these changes are minor, we understand it may require some effort from users to implement. Given this, we have postponed the implementation of GDA2020 slightly to allow additional preparation time. The GDA2020 implementation will now be scheduled for 24 July 2022.
For technical information on the GDA project implementation please go to our GDA2020 Information page.