Hydrogeological entities — Métropole

The hydrogeological entity is a part of the geological space, aquifer or non-aquifer, corresponding to a physical system characterised by its state and hydrogeological characteristics. The hydrogeological entity must be understood in a systemic sense and corresponds to a breakdown of the geological space realised at a given stage of knowledge in particular for deep systems. The constitution of hydrogeological entities is derived from knowledge at a given date of the underground environment (geological map, geological cutting, geological log, structural diagram and piezometric map). Hydrogeological entities can be multi-part. Hydrogeological entities cover the entire territory ensuring a horizontal and vertical relationship of entities in accordance with the principle of completeness. A hydrogeological entity is a part of the geological space: — delimited on a certain scale (level d' use) — attached to a type of geological formation (theme) — defined by its aquifer potentialities (nature) — characterised by a type of porosity (mid) — characterised by the presence or not of a tablecloth, which may be free, captive or free and captive (state) They have been defined according to rules developed within the framework of a common national methodology and validated by a national steering committee under the responsibility of the Ministry responsible for the environment. A hydrogeological entity will be represented by its orthogonal ground projection. The reference scale is the 1/50 000th, i.e. the national geological reference scale. Each entity has a code that is assigned by the BRGM (Order of 26 July 2010, SNDE). (D' after Sandre, dictionary of the hydrogeological reference SAQ V 2.1) __Origin__ The entities disseminated are entities at local level (NV3). These entities have " parent entities; at the regional (NV2) and national (NV1) levels, these associations are described in the multi-scale table downloadable above. __Partner organisations__ Ash, Bureau of Geological and Mining Research __Links annexes__ * [see the interactive dictionary on Sandre website](http://www.sandre.eaufrance.fr/?urn=urn:sandre:dictionnaire:SAQ::entite:EntiteHydroGeol:ressource:2.1:::html) * [see BDLISA’s delivery description v.2](http://www.sandre.eaufrance.fr/sites/default/files/document-sandre/Descriptif_données_BDLISA2_v3.pdf) * [consult the monitoring report of hydrogeological entities online](http://mdm.sandre.eaufrance.fr/geo/rapports/public/EntiteHydroGeol) * [recover an anomaly or propose a correction on the BDLISA forge](https://forge.eaufrance.fr/BDLISA) * [download Level 3 Hydrogeological Entities — Metropole BDLISA v.2 — Geodatabase Format](http://services.sandre.eaufrance.fr/telechargement/geo/SAQ/BDLISA/2/FXX/BDLISA_V2_FXX-gdb.zip) * [download Level 3 Hydrogeological Entities — BDLISA Metropole v.2 — SQLite Format](http://services.sandre.eaufrance.fr/telechargement/geo/SAQ/BDLISA/2/FXX/BDLISA_V2_FXX-sqlite.zip) * [download Level 3 Hydrogeological Entities — Metropole BDLISA v.2 — Format gpkg](http://services.sandre.eaufrance.fr/telechargement/geo/SAQ/BDLISA/2/FXX/BDLISA_V2_FXX-gpkg.zip) * [download batteries of #x27; hydrogeological entities BDLISA v.2 Metropole — CSV Format](http://services.sandre.eaufrance.fr/telechargement/geo/SAQ/BDLISA/2/FXX/PileEntiteHydroGeol_FXX-csv.zip) [See this page on geo.data.gouv.fr](https://geo.data.gouv.fr/fr/datasets/a04624bb77b104521af2c6e52d5df773433d1a9b)