Storm zoning

**Zoning of the Paris Rainfed Regulations** The Paris rain zoning regulation, called “ParisPluie”, has been enforceable since March 2018. It aims to manage rainwater as close as possible to where it falls and thus limit its intake into the sewerage system. Its principle is to cut the first millimetres of rainfalls on any ground or set of land, public or private, within 24 hours, as long as its area is eligible for rain zoning regulations. We speak of a minimum volume abatement (4, 8, 12 or 16 mm depending on the location). The excess volume is transferred to the sewerage system. The optimum objective, which can of course be sought, corresponds to the total disconnection of rainwater, which means no discharge into the sewerage system regardless of the type of rain until the ten-year rain (48 mm in 4 hours). The map of the Paris rain zoning was built according to the hydraulic operating rules of the sewerage network and the geological characteristics of the basement. To know the abatement zone in which a project is located (minimum objective to be achieved), it is the situation of its connection point to the sewerage system that counts (address of the existing connection or to be created). Peculiarity of the hatched area: in this area, the additional requirement applies for any project with a reference area of more than 2 500 m² to regulate the leakage rate at 10 L/s/ha from the discharge of unreduced rainwater volumes to the sewerage system, at least up to ten-year rain. **Documentation & Mapping:** To access the Paris Umbrella Regulation and Guide, please refer to the following page: [**Plan Paris Rain**](https://www.paris.fr/pages/le-plan-parispluie-5618/) **[Mapping of the rainfed zoning of Paris](https://capgeo.maps.arcgis.com/apps/Media/index.html?appid=fc5c34dcaccb4e1983d1367f12da0e4c)**