Surface water

Surface waters comprise rivers, lakes, transitional and coastal waters. Surface waters are located in diverse natural spaces and differ from each other regarding the catchment area geology, their morphology and the existing flora and fauna. Therefore a system was developed, which compiles the waters into water types, according to their natural spatial features and considering common characteristics. The sections of a water stream of the same type, which also display some other important boundary conditions uniformly, such as stream characteristics and main impacts, are designated as water bodies. Water bodies in coastal waters are delineated according to their salinity and depth, whereas lakes are generally not delineated into further water bodies. Surface waters are also delineated in natural and artificial water bodies. Concerning the morphological alterations,natural waters can further be designated as heavily modified water bodies. This difference is important in regard to the environmental objectives required. The requirements regarding the heavily modified and artificial waters are less stringent than those regarding natural waters, due to their particular water uses.

Groundwater

Groundwater is subsoil water, which coherently fills the soil pores.
Regarding the geological relations, several groundwater floors can lie on top of each other with the single aquifers separated from each other by impermeable layers. Ground water is a part of the natural water circulation and at the same time our greatest and most important fresh water storage. Springs, rivers and lakes get water from it. Ground waters which are located close to the surface provide plants with water and allow the development of valuable wet biotopes. Groundwater bodies constitute the principal basis of our drinking water supply.

A groundwater body in terms of WFD is a delimited groundwater volume within one or several aquifers. However all observations refers comprehensively to the shallow aquifer (main aquifer) which is relevant in terms of water management.