Geoscience Reference
In-Depth Information
1.7
example, sediment may be having an adverse
impact upon the ecological functioning of a river
basin, or excess sediment accumulation may be
having a negative impact upon the economic
functioning of a port or other navigable water-
way. In most cases, these issues will be about
either sediment quantity or sediment quality,
although in many cases they are interlinked
(see Case Study 1.3).
ASSESSMENT AND MANAGEMENT OF SEDIMENTS
Sediments are managed on many scales (both
spatially and temporally) for a wide range of
reasons, and different environments have unique
management challenges and solutions (see indi-
vidual chapters). In many cases it can be recog-
nized that there is a problem from the sediment
perspective which needs to be addressed. For
Case study 1.3 Sediment dredging and treatment in the Port of Hamburg, Germany
Hamburg harbour is the largest port in Germany, and one of the ten largest in the world. It is
near the mouth of the River Elbe, approximately 100 km from the North Sea, which drains
central Europe (Case Fig. 1.3A). As it is an economic port, water depths need to be maintained
to allow shipping access into the port. Sediment is supplied to the port both from the upstream
catchment of the River Elbe, but also by tidal movement of sediment from the North Sea.
Sedimentation rates in some parts of the port are in the order of several metres per year, and this
sediment accumulation has a major impact upon shipping access. As a result, there is a need for
sediment to be dredged from the port; approximately 3 to 4 million cubic metres of sediment
from the Elbe each year.
This creates an issue of how to dispose of this dredged sediment. Before the 1970s this
dredged material was either placed on agricultural land or disposed of further down the system.
However, high levels of contamination in this sediment, together with stricter environmental
Czech
Republic
N
Hamburg
ELBE
Prague
Border of
catchment area
Germany
50 km
Case Fig. 1.3A
The drainage basin of the River Elbe, which drains central Europe and has near its mouth the harbour of
Hamburg, the largest port in Germany.
