Keeping the river Weser at depth is vitally important for the harbour group Bremerhaven and Bremen, forming the second largest port in Germany. Over the past years Bremerhaven developed to one of the largest container and automobile ports in Europe. The seaport Bremerhaven is prominent for its impressive 5 kilometre long container terminal.
As a member of the so-called "Hamburg-Antwerp-Le Havre Range" – the seaports on the southern North Sea – Bremerhaven is in competition with the other ports of this area, in particular with Rotterdam and Antwerp. To maintain this position, Bremerhaven is continuously investing in the port and its access. Trade is vital to the prosperity of the region, and as a result it is crucially important to guarantee navigational depth for modern vessels on the river Weser.
As the body that is responsible for navigational depth and for ensuring safe passage from the North Sea to the harbour group Bremerhaven and Bremen on the river Weser, the ‘Wasser- und Schifffahrtsamt’ in Bremerhaven calls for tenders according to specifications for the maintenance dredging.
Following several earlier maintenance contracts on the river Elbe and Jade, Nordsee Nassbagger- und Tiefbau GmbH was awarded the 24 months dredging campaign for the years 2015 and 2016 on the river Weser. The contract covers a 130 km stretch of the river between Weser-km 40 and 130, including the turning basins of the areas Brake, Nordenham and Bremerhaven.
Several trailing suction hopper dredgers (TSHD) were and are assigned to the 2015-2016 maintenance dredging campaign on a 130 km stretch of the river Weser. Their optimal size is in the 4.500 to 5.600 m³ range, but also ≥ 8.000 m³ TSHD are scheduled.
As a constant deployment of the TSHD over the full 24 month is not assured, one particular feature was to minimise the downtimes resulting from fluctuating quantities to be dredged. This was achieved by adapting the hopper size and by optimising the timing for vessel changes.
Furthermore a dedicated onshore team has been selected to focus on several defined improvement levers to increase productivity.
Nordsee Nassbagger- und Tiefbau GmbH has executed similar maintenance dredging projects on several German estuaries for the past decade, which constitutes a clear proof of confidence from the respective ‘Wasser- und Schifffahrtsamt’ in Wilhelmshaven, Hamburg, Emden, Cuxhaven and, for this project, in Bremerhaven, the client. For 2015-2016 an approximate volume of 14 million m³ of sand and mud is estimated to be dredged and dumped at various locations of the river Weser.
Special attention is given to the turning basins of Brake, Nordenham and Bremerhaven to always guarantee sufficient depth and room for a safe manoeuvre of the vessels entering and leaving the port of Bremerhaven.