AZI Coastal water courses — Limit of the study area in the Loire-Atlantique

These data represent the boundary of the zone d'atlas study of flood zones of coastal rivers. The study perimeter of the flood zones (AZI) of coastal rivers covers the watersheds of the Etier du Pont d’Arm, du Boivre, the Canal de Haute Perche and Falleron (including its upstream part located in the Vendée department). The confluence zones of the 4 coastal watercourses with tributaries are treated (a few hundred meters depending on the configuration of the terrain). On the other hand, the atlas of flood zones does not cover the tributaries themselves. __Origin__ L' study led by the DDEA of Loire-Atlantique applies to the overall linear of the 4 courses d' coastal water the hydrogeomorphological method for determining floodable areas. This naturalistic approach based on the analysis of the forms and formations of valley bottoms makes it possible to do so; identify the different beds of the river. It is complemented by research d' archive on historical floods. L' analysis s' supports the geomorphological interpretation of n°#x27; stereoscopic cover of aerial photos validated by field checks The hydrogeomorphological study consists of maps of inundability carried out at the scales of the 1/25.000e on a background formed by SCAN 25 of l'I.G.N. and 1/10 000e for areas at stake on the #x27th; orthophotoplan. __Partner organisations__ DDTM Loire-Atlantique __Links annexes__ * [Atlas-des-zones-inundables-des-cours-d-eau-cotiers](http://www.loire-atlantique.equipement-agriculture.gouv.fr/Politiques-publiques/Risques-naturels-et-technologiques/Prevention-des-risques-naturels/Atlas-des-zones-inondables/Atlas-des-zones-inondables-des-cours-d-eau-cotiers) [See this page on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/e69dc5732052ed6f042dbada999d0abe9282f8e9)