The Role of Positioning Infrastructure and Mapping Surveys in 3D Cadastre Implementation for Mass Rapid Transport Infrastructures – Indonesia Case

Abstract

In response to recent increases in the utilization of 3D spaces situated below and above land surfaces, both users and registrar increasingly demanding a reliable positioning infrastructure for a cadastre. This paper discusses some challenges and requirements for establishing a reliable positioning infrastructure to support 3D cadastre implementation in Indonesia. Since three decades ago, ground survey marks (TDT) have been conventionally used for parcel mapping and only have 2D coordinates. TDT can be used for 3D cadastre implementation by assigning the TDT height to the national height datum. Surveyors can define the TDT height by referring to the orthometric height pillars (TTG) or the Indonesian national geoid (InaGeoid). These two references are sub-elements of the 2013 Indonesia Geospatial Reference System (SRGI 2013), which since 2013 has been used as a reference for various geospatial data nationally. 2D parcel mapping practices in Indonesia are still referring to the previous reference system used by Indonesia, namely the 1995 National Geodetic Datum (DGN95). This condition makes an integrated 3D survey to support first registration and right transfers for 3D Cadastre is challenging. At the same time, a 3D validation survey for 3D cadastre aiming to validate X,Y and Z coordinates of 3D parcels to be registered needs to be done efficiently and accurately. This paper discusses challenges regarding coordinates shift, inconsistencies between 2D and 3D parcels, missing height references and lack of coordinate redefinition of GPS coordinate services. This paper will examine the 3D cadastral validation survey results done in the Mass Rapid Transit (MRT) stations in Jakarta City and evaluate the positioning infrastructure in Jogjakarta City where an MRT connecting the new airport to the city centre will soon be built.