ABSTRACT
It could have been a fairly straightforward infrastructure project. The Hamburg Port Authorities anticipated an increase in the draught of future ships. These ships extend deeper in the water and the Unterelbe River between Hamburg and the North Sea was deemed to be too shallow to receive such ships. Consequently, a plan was made to deepen the Unterelbe. The Unterelbe was deepened, and for a while everything seemed fi ne. However, two years after the deepening operation, the physical system responded with a dramatic change in the amount of sediment accumulation. The volume of sediment accumulating in the harbor doubled in 2001 and doubled again in the years following. Apart from the rising cost of dredging the harbor, the sediment accumulation also eliminated the very reason for the deepening, since it reduces the amount of depth available to ships.
