The agreement between the port management company Bremenports and its partner organisation Hafenbedrijf, Rotterdam, involves the removal of 60,000 cubic metres of material from the bottom of Überseehafen that will be deposited in ‘De Slufter’ over an eight week period by the hopper dredger “Hein”. The work is expected to be completed by the beginning of March.
Constantly looking for alternative disposal sites to ease the strain on the limited capacities of its own facility in Bremen-Seehausen, which annually can accommodate approximately 200,000 cubic metres of silt, Bremerhaven is the first foreign port to permanently dispose dredged material in Rotterdam. Bremen’s Senator for the Environment and the Dutch government have both approved the scheme.
Most sediment occurs behind the locks in Bremerhaven as a result of seagoing vessels passing through the locks. To compensate for this, water from the Weser, which contains suspended matter is regularly pumped into the harbour, however the harbour sediment contains contaminants. Dumping of this sediment in the old fairway in the Outer Weser was stopped in 1997, since when it has been taken to a special disposal facility in Bremen to be drained and deposited in compliance with environmental requirements.
In recent years silts have also been taken to the Lower Rhine for reclamation of abandoned gravel pits.
Constructed to accommodate dredged material from Rotterdam and the Dutch waterways, the ‘De Slufter’ site became operational in 1987 and can hold around 150m cubic metres of silt. The disposal site consists of a 28 metre deep pit enclosed by a 24-metre high ring dyke, where dredged material is pumped in through a floating pipeline.