Rīga Municipality maintains a large scale (1:500) topographic information database, which includes information on underground infrastructure, i.e., power grid, sewerage, rainwater drainage system, gas pipelines etc. The data is maintained in vector data formats consisting of 600+ data levels/objects and split in 1000+ and more maps/planchets. To maintain and update data a proprietary software is used. In order to promote data exchange with other potential data users, it is important to ensure data exchange and compatibility with other data systems/ data users and the possibility to add additional data to the municipal database. Existing data structure and software does not allow to execute data exchange and updates effectively as data transformation processes must be involved. However, this data is very valuable, it is hardly used in building and urban modeling as 3D models.
The challenge our city faces is understanding and managing its underground urban space. This includes utility networks (e.g. water and electricity), traffic tunnels, archaeology, geology, ground water and natural entities (e.g. tree roots or habitats for fauna) These underground elements are crucial for the city’s functioning, but they are often hidden, making it difficult to capture reliable data and visualize it.
The Brussels Region, with an area of 16,300 hectares, is largely green, with more than half of its territory (52%) covered in vegetation. Tree vegetation represents approximately a third of the total surface area (31%). However, when we exclude the UNESCO heritage Sonian Forest (1,650 hectares), the area of green spaces per inhabitant is on average 12 m², barely higher than the minimum acceptable threshold of 10 m² per inhabitant. This regional average hides significant disparities between neighborhoods, with the least vegetated areas being mainly located in the city center. Densely built neighborhoods leave little room for public spaces and private gardens, while narrow roads offer little opportunity to accommodate trees or other types of vegetation. Brussels regional and municipal administrations have become aware of the benefits of green spaces and are increasingly planting and monitoring the characteristics of their trees (species, heights, diameters, years of planting, phytosanitary diagnostics, etc.).
However, while the importance of trees in the urban environment is undeniable, it is also often downplayed and lost among the myriad of other competing factors involved in the creation, management and maintenance of urban spaces. While the aerial parts of plants often have fairly regular growth, the root systems have a much more complicated growth. The subsoil is in fact a heterogeneous environment of great diversity where we find in particular soil layers, networks (drinking water, waste water, electricity, gas, telecommunications cables, urban heating networks, electrical charging of vehicles …), abandoned underground infrastructures (cables, pipes, etc.), building basements, geotechnical objects, geothermal probes, etc., tunnels, water tables, archaeological sites, etc.
