Capacity Building in Africa: Training the Next Generation of Surveyors in Building High-Accuracy Digital Twins in South Africa

During the Federation Internationale des Geometres (FIG) Annual Meeting 2026 in Cape Town, the Department: Land Reform and Rural Development (DLRRD) will demonstrate its approach to high-resolution 3D mapping. By combining long-dwell DGNSS surveying, Continuously Operating Receiver Stations (CORS) DGNSS, and DGNSS-enabled drones, we have been able to map urban, rural, remote, and indigenous regions with 5 cm absolute accuracy, with a significant increase in efficiency over traditional ground surveying.<br />The intention of the training is to provide a comprehensive and detailed demonstration of the methodology. For executives and directors, we will focus the first and last sessions on understanding how to be an effective consumer of high-accuracy 3D collection programmes. The intermediate sessions will take the participants through an accelerated collection program, including participating in the collection of a site in the Cape Town area. Participants will perform mission planning, collection planning, collection execution (including ground control surveying in the field), post-processing, quality control, exploitation into GIS/GISc and digital twins, and post-mission documentation, including an out brief to the executive/director participants.<br />Historically, the maintenance of authoritative geodetic databases is the function of the national geodetic survey organizations, such as the Chief Directorate: National Geo-spatial Information (CD: NGI) in South Africa and their equivalent organizations worldwide. Every authoritative 3D database suffers from a burden of currency and completeness, in which the time between resurvey events defines an epoch during which the previous survey ages sufficiently to be marginally adequate for current needs. Issues of cost, access, and update frequency limit the quality, coverage, and currency of any curated database.<br />The transition to hybrid surveying using drones provides a unique opportunity in that the drones directly exploit the local and national geodetic DGNSS framework and produce dense, high-resolution, highly accurate 3D imagery. This hybrid surveying approach was pioneered by the Survey of India in the Survey of Villages Abadi and Mapping with Improvised Technology in Village Area) (SVAMITVA) project that successfully mapped 60 million rural land parcels.<br />South Africa has embraced this model and applied it directly to mapping 836 Indigenous regions that lack detailed property maps. DGNSS-enabled drone surveys extend the precision and accuracy of RSA&rsquo;s DGNSS network (TrigNet) for cadastral mapping of property suitable for its Land Planning Programme (LPP). DLRRD is building a prototype of an off-grid, locally managed, and operated GISc work site built into transportable containers that bring the GISc, communications, and drone infrastructure to the local community.