Wetland landscape 

The plant communities along the shore of a river or a stream are called “wetland landscapes”. Only the plants that can adapt to the conditions of fluctuating water level can grow there.

Internal waterway transport 

Internal waterway transport that takes place on rivers, seas etc.

Compensatory measures 

Regarding nature conservation areas: Measures for avoiding the loss of a nature conservation area. This usually happens when there is an attempt to prepare an additional area in order to host a similar biotope, so that the previously existing protected area may exist in a new location. Many environmentalists criticize such measures (see, for example, the opinions on the environment that are available at the station on the harbours).

HGK 

HGK / Hafen und Güterverkehr Köln AG (Harbour and Goods Traffic Cologne PLC): The HGK is a company that belongs to the City of Cologne which is responsible for the management of the commercial harbours of Cologne.

IHK 

IHK / The Chamber of Industry and Commerce of Cologne: The IHK represents all companies in a certain region. Some of its responsibilties include the coordination and implementation of exams for vocational education.

Water level 

The height of the water level according to a defined status of water depth.

Renaturation 

Renaturation means the reconditioning of natural habitats, in other words, the attempt to reverse changes to nature caused by humans. Attempts are frequently made, for example, to (partially) realign rivers to their original course.

Retention space 

Retention space / Flood detention space: an area that may be inundated in the case of flooding in order to reduce the water level/flood wave. An area that is automatically inundated in the case of flooding, due to its natural conditions, is regarded as a natural retention space.

Apex 

In regard to flooding: the highest level of the flood wave.

Threshold 

Threshold: elevation. In regard to flooding: the point under which a certain area cannot be flooded.