Nodal point

Key point for water management usually defined downstream of reference hydrographic units for sub-basin management plans (SAGEs) and/or within those units whose boundaries can be determined by the river basin management plans (SDAGEs). At these points, benchmark values for flow rates and quality can be defined according to the overall objectives selected for the unit. Their location is based on consistency criteria for a river basin, an ecosystem, hydrogeology and socio-economy.