Evolution of the ecological status/potential of surface water bodies

The European Water Framework Directive sets the goal of “good status” for water bodies. For natural surface waters, this means, among other things, good ecological status. For artificial and heavily modified surface waters, the targets may be lower (= good ecological potential). The biological quality elements phytoplankton, macrophytes, phytobenthos, macroinvertebrates and fish and a number of hydromorphological, chemical and physicochemical parameters determine the ecological state. In the final assessment, water bodies are classified into classes (‘very good’, ‘good’, ‘moderate’, ‘inadequate’ and ‘bad’).