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Towards a 3D Data Model of Underground Utilities for Land Administration

Cities around the world face an increasing need for land as density in urban areas increases rapidly. The pressure to expand a city's space is especially acute for a city-state like Singapore. In the big data era, a data-driven approach of underground spaces is necessary for the sustainable development of a city along with rapid urbanization. A reliable three dimensional (3D) digital map of utility networks is crucial for urban planners to understand one of the most impactful aspects of underground space planning. How to map reliable 3D underground utility networks and use it in the land administration? This is a challenging issue, especially for cities with limited land resources, congested underground spaces, and a lack of uniform existing practices. First, this paper proposes a framework for utility data governance from the underground utility data survey to data usage. This is the backbone to support coordination of different roles in the utility data management and usage. Then, an initial design of the 3D utility cadastral data model is introduced, which aims to support the 3D modelling of utility networks and connect it to the cadastral parcel. It is expected that reliable and accurate information on underground utility networks can lead to a better understanding and management of underground space, which eventually contributes to better city planning, making the unseen structures visible.