DIN EN 16503:2014-11

This document gives guidelines for characterizing the hydromorphology of transitional or coastal waters. The main aim is to improve the comparability of hydromorphological survey methods, data processing, and the interpretation and presentation of results. In a general sense, transitional waters (for example estuaries, fjords, some lagoons) are neither fully open coastal systems nor enclosed or flowing freshwater areas. Their boundaries can be defined by hydromorphological features and discontinuities, by salinity, or by any other hydrographic feature (for example water depth and tidal regime). The term "coastal waters" has been defined for various legal and political purposes but in this hydromorphological standard they are defined as waters characterized by coastal features and influenced by coastal processes. This European Standard serves for: a) the support of environmental and conservation agencies in meeting monitoring requirements of the WFD and MSFD; b) the generation of data material appropriate for monitoring and reporting on the condition of Natura 2000 sites designated under the Habitats Directive and the Birds Directive; c) the provision of information supporting other environmental reporting requirements (for example in relation to biodiversity or environmental impact assessments); d) the support of management and restoration initiatives. This European Standard: a) defines the term "hydromorphology" and other technical terms relating to the physical characteristics of transitional and coastal waters and their hydrological regime; b) lists essential features and processes of TraC waters that should be characterized as part of a hydromorphological survey and used for determining hydromorphological condition; c) identifies and defines the main pressures affecting European transitional and coastal waters; d) gives guidance on strategies for collecting and presenting hydromorphological data depending on the resources available and the anticipated use of the assessment; e) provides guidance on data quality assurance. This European Standard does not deal with biological assessments in transitional and coastal waters such as the presence or absence of individual species or community composition, nor does it attempt to link specific hydromorphological features with their associated biological communities. However, it is relevant where plants or other organisms form significant structural elements of the habitat (for example saltmarshes, biogenic reefs). Hydromorphology of transitional and coastal waters is one of the basic features of marine and coastal ecosystems controlling the presence of biota. Hydromorphology is the result of the interaction between the structure of the systems and their functioning. Structure includes sea-bed geology, sediment features, morphology and water depth, whereas functioning includes hydrodynamics, sediment dynamics and morpho-dynamic processes. Over the past several millennia, human developments in transitional and coastal waters throughout Europe have caused substantial changes in the hydromorphological characteristics and ecological functioning of many water bodies. Hydromorphological changes are an important consideration in implementing the Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD). In addition, for the Habitats Directive there is a need to maintain certain 'features' in favourable condition, which has also given rise to a focus on hydromorphological assessments. Note that in this standard, "assessment" is used as a broad term referring to the general description of features and the pressures that impinge upon them. It is not used to imply the judgement of particular levels of "quality" or "value", whether related to status under the WFD, MSFD or more generally. The preliminary work has been carried out by Working Group "Biological methods" (WG 2) of CEN/TC 230, the chairmanship of which is held by BSI (secretariat: United Kingdom). Regarding the German collaboration, the responsible committee is NA 119-01-03-05-06 AK "Biologisch-ökologische Gewässeruntersuchung" ("Biological-ecological water examination") of NA 119-01-03 AA "Wasseruntersuchung" ("Water examination") at the Standards Committee Water Practice (NAW).