GIS and web-mapping

DSC Spatial Services have committed to provide Foundation Spatial Data in GDA2020 by 30 June 2020, and to continue to support GDA94 until 30 June 2023 (i.e. for 3 years).

GIS users need to incorporate GDA2020 and associated transformation capabilities within their GIS systems. Provided you can receive and supply data clearly identified as GDA94 or GDA2020, and align them through transformation, your current GIS workflows can remain on GDA94 for the short-term. When your organisation is ready and your needs and applications demand, you can convert existing workflows to GDA2020.

GIS users should confirm with their vendor that their software meets their GDA2020 requirements.

GIS software supporting the NTv2 grid transformation is recommended.

ICSM’s GDA Transformation Products and Tools may assist with planning your transformation strategy.

WGS84 and Web Mercator: Potential for misalignment

WGS84 (and its Web Mercator projection) are the defacto standard for many web mapping applications. Users should be aware of potential accuracy issues concerning WGS84 when working with datasets of metre-level accuracy or better.

WGS84 is a time-dependent datum and metre-level misalignments can occur if a timestamp is not provided. Refer to this WGS84 information sheet.

Where DCS Spatial Services provides data and web services in WGS84, these will be provided in WGS84@1994.0 (i.e. the nominal equivalent of GDA94) unless otherwise indicated, to align with existing cached GDA94 and WGS84 data in Australia.