Managing rainwater in Paris, atlas of each catchment basin potential

A change in the rainwater management paradigm has been reinforced in recent years by regulations making local infiltration obligatory within the framework of the newly established Rainwater Zoning Plan.

Greened bases of trees in Paris, Bd Raspail (14) © Apur

Continuing the large amount of work already carried out on this theme, this study, made by the Paris Urbanism Agency (Apur), locates and quantifies areas which are already permeable and/or greened and proposes an estimate of potential deimpermeablization/disconnection for each of the 18 Parisian catchment areas that is 97% of Paris’ surface area excluding the woods. This work is brought together in a cartographic atlas of Parisian water catchment basins with completely new maps.

The work puts forward the hypothesis that all urban spaces can contribute to the infiltration, evaporation, use of rainwater. Water can be gathered where it falls, on a roof, in a courtyard, on a garden, pavement, at the foot of continuum or random trees. It is therefore a question of working with the city as it is and looking into every opportunity offered by water at the level of its own natural cycle.

At this time of climate change, the local management of rainwater is of major importance. To illustrate this, intercepting the first 8 to 10 millimetres of rainwater in 24 hours and thus disconnecting it from the drainage system contributes enormously to easing the pressure on large water-works, reducing the high cost of this process and in addition favouring greening and the battle against heat islands. 

This atlas reveals that over 23% of the land considered could be rendered permeable / be disconnected according to the hypotheses, that is 1.895 ha. (252 to 269 ha. on public space, 1.642 ha. on land plots), and added to the 18% of surface areas already estimated to be permeable, that is 1.454 ha. (111 ha. on public land, 1.343 ha. on land plots).

Carried out in close liaison, notably with the technical office of the Department of Clean Water (Direction de la propreté et de l’eau), as well as with other City of Paris Departments, this work also describes a series of indicators developed in order to monitor and assess these actions as well as to develop suitable tools to deal with the environmental challenges  and objectives. One more step taken towards a more resilient city.

Infographie - Gérer les eaux pluviales à Paris, atlas du potentiel par bassin versant © Apur


Documents to download

  • Study

    Managing rainwater in Paris, atlas of each catchment basin potential

    Format : pdf, 43.14 MB

Maps to download

  • Map

    Potential deimpermeabilization /disconnection in Paris

    Format : pdf, 1.44 MB