The Greater Paris Metropolis today has 220 km of rivers, streams and canals. There were approximately 410 km of them in 1900. By finely mapping these visible water networks, the Workshop highlights both permanent and ephemeral waters as well as the water lines that cross the territory.
Today 220 km of rivers, brooks and canals run through the Greater Paris - Grand Paris Metropolis -, in 1900 there were 410 km. By finely mapping these visible bodies of water, the agency sheds light on permanent and ephemeral waterways as well as other watercourses that flow through the territory.
Visible water now represents 2.25% of the surface area of Grand Paris. By documenting this water as well as old brooks and rivers and geo-referencing their trajectories, it is possible to reconstitute coherent courses on the scale of the metropolis using a detailed digital terrain model. This reconstitution makes it possible to reconstruct the main catchment basins of the principal rivers (Seine, Marne, Orge, Yvette), as well as existing brooks and streams (Croult, Morée, Petit-Rosne, Vieille-Mer, Chantereine, Merdereau, Morbras) and those which have disappeared (Ménilmontant, Charonne, Montfort, Clamart, Sèvres, Meudon, Montreuil, Châtenay…).
Through the approach of identifying watercourses, rivers and catchment basins one becomes aware of where waterways run which can accompany projects in public or private spaces, the continuity of parks and gardens, streams, ponds, springs and open air run-offs. The rediscovery of brooks and rivers has been underway over recent years and is currently ongoing. The study of the potential hydromorphological restoration launched by Grand Paris Metropolis in 2023 should enable these projects to be followed through and relevant action to be given priority.
The complementary nature of resources and networks, be they open-air or subterranean, natural or artificial, leads to many different strategies linked to water in the city: the conservation and enhancement of water ressources, climate change, networks and ecosystems, aesthetic and recreational qualities etc. The lines of thought and tools for exploring urban water cycles have broadened and include issues of rediscovering and evoking the presence of water, the links between the network and exceptional climatic conditions (too much or not enough water).Mapping waterways reminds one of their beauty and fragility through time, and offers an opportunity to consider their future. To give water a place in the metropolis, means reconsidering both the geography and history, water run-offs and resources, cooling and biodiversity.
