Exploiting 2D/3D Geomatics Data for the Management, Promotion, and Valorization of Underground Built Heritage

The scarce knowledge and documentation of Underground Built Heritage (UBH) assets frequently limit their full exploitation and valorization. The aim of this work is to reflect on the techniques, functions, and technical features of a specific case study in a very broad context that can, however, be a building block for the understanding, preservation, and reuse of architectural and engineering values that represent a fundamental trace of the history of a society. Therefore, to fill these knowledge gaps, it was constructed a 3D GIS model, multi-scale, and interoperable database, capable of management, promotion, and valorization of UBH. The case study focuses on the old water supply system of the city of Lisbon, as UBH site, with galleries and cisterns that are points of connection with the urban environment above. For the creation of 3D models of the structure under investigation, it was decided to carry out a survey with Mobile Mapping System as a first step, which allowed the construction of a dense point cloud useful to build 3D models of individual objects. Finally, the 3D models were imported into the 3D GIS environment and multi-information could be linked for each previously identified element for greater knowledge sharing. This research has demonstrated how geomatic techniques can be effectively used in conjunction with the information management systems of GIS to explore this “hidden” heritage and has highlighted the limitations and problems of 3D digitization of the UBH. The results obtained offer the possibility of extending and adapting the methodology to different application contexts and the possibility of customizing the data representation.