Body of groundwater of order 9

A body of groundwater is a distinct volume of groundwater within one or more aquifers. Groundwater bodies are derived from work carried out on the BDRHF v1 repository. The cut-off for water bodies follows the following key principles: — Water bodies are demarcated on the basis of geological and hydrogeological criteria, — The redistribution of water bodies to take account of the effects of anthropogenic pressures must remain limited. — The boundaries of water bodies must be stable and durable — Like surface water bodies, the demarcation of groundwater bodies is organised from a typology. This typology is largely based on that developed for hydrogeological entities defined as part of the revision of the RHF BD. It is based on the geological nature and hydrodynamic behaviour or “big” functioning of aquifer systems (nature, flow rate). It has 2 levels of characteristics (main and secondary). — Water bodies may interact with each other — All abstractions providing more than 10 m³/day of drinking water or used to supply water for more than 50 people must be included in a body of water — Deep groundwater, unrelated to rivers and surface ecosystems, from which no sampling takes place and which is not likely to be used for drinking water because of their quality (salinity, temperature?), or for technical and economic reasons (cost of disproportionate abstraction) may not constitute water bodies. — Given its size, a body of water may have a certain spatial heterogeneity in terms of both its hydrogeological characteristics and its qualitative and quantitative status. — At any point several bodies of water can be superimposed. (source: BRGM, WFD IMPLEMENTATION: Identification AND DELIMITATION OF SOUTERRAINE WATER MASSES — methodological guide, January 2003)