4.     Hydromorphological pressures and impacts

4.1.    Drivers and pressure of hydromorphological alterations

4.1.1.      Drivers and activities

Hydromorphological pressures comprise all physical alterations of water bodies modifying their shores, riparian/littoral zones, water level and flow, (except water abstraction). Examples of such pressures are damming, embankment, channelization, non-natural water level fluctuations. The extent of hydromorphological alterations in European river basins has been significant over the past centuries. Hydromorphological pressures are the consequence of human activities (drivers) in the catchment area including hydropower production, flood defence structures, navigation, agriculture, land drainage, urban development and fisheries. Hydromorphological changes may result from more than one activity (e.g. a multi-purpose dam for hydropower generation, water supply and flood protection).