The contribution concerns the trial entitled 'Brussels' visible water', a mainly visual trial based on a reading of the hydrographic system in the Vijevers Van Elsene and Flagey-Malibran districts, both in the commune of Ixelles and located in the upper part of the Maelbeek catchment area. If the rainwater collection system is completely buried, during heavy rainfall the water in the drainage system tends to come back to the surface and can cause major damage. The work then develops some of the results of the 'Water vs Urban Scape' workshop and puts forward the hypothesis of a radical scenario: it envisages all the rainwater that falls within the Maelbeek catchment area being treated on the surface as much as possible, giving life to a new, extensive and non-hierarchical hydrography that would cover the entire catchment area.