Ecomorphology refers to the physical characteristics of a waterbody and its riparian zone. In recent decades, as a result of the development of settlements and transport infrastructure, and the intensification of agriculture, the space available for watercourses has been increasingly restricted. The natural course of streams and rivers has been modified by extensive engineering works designed to provide flood protection for settlements, infrastructure and crops.

In many cases, structural works of this kind adversely affect the capacity of watercourses to fulfil ecological functions. If a watercourse is to serve as a habitat, near-natural morphological and hydrological conditions are required in addition to good water quality. Thus, the Water Protection Law and Ordinance - the legal foundations for the attainment of these goals - seek to promote near-natural morphology for waterbodies as well as appropriate water quality.

• variability of water width
• modifications of the channel bed
• modifications of the river banks
• width and structure of the riparian zone.

When the individual parameters have been evaluated using a points system, sections of rivers and streams are assigned to one of four different categories and can then be mapped using colour codes so as to provide a rapid overview of the ecomorphological state of a region's watercourses.