To build the 16 km long bridge-tunnel link from Denmark to Sweden requires the dredging of extremely hard layers of limestone, often in extreme weather conditions, with strictly controlled spillage limitations.
Offshore sand and gravel at depths of -60 metres form an important economic resource. Accurate assessment of these offshore deposits are important to prevent environmental problems, conflicts and delays.
The environmental impact of turbidity depends upon the dredging technique used; the ease with which the sea bed material becomes resuspended; and the condition of the surface water. An on-site analysis is advisable.
Research has proven that most material dredged from Scotland's Firth of Clyde is clean. By dumping it at sea, port authorities are missing the opportunity to use this clean dredged material for beach nourishment and coastal erosion prevention.
To satisfy EC bathing water quality directives, a new, longer outfall was needed. Dredgers had to reckon with the recreational importance of Spain’s beaches, plus the existence of an operative gas pipeline.
By shifting from port-operated dredging to privatised contract dredging, three New Zealand ports have moved from world-ranked laggards to the top echelon of international ports in terms of profitability and performance.
Laboratory experiments demonstrate from a wear point of view the inefficiency of cutting tools on a cutter suction dredger. Recommendations are made to optimise the cutterhead design and cutting process.