Marine sand and gravel extraction in the North Atlantic and its potential environmental impact, with emphasis on the North Sea

This paper reviews the dredging of aggregates in the North Atlantic, North Sea and Baltic Sea area in the period 1979–1985. It is estimated that the following average amounts are extracted per year: sand for building purposes 40 million m³; gravel 9 million m³; calcareous material 1 million m³; maintenance dredging (sand) 400 million m³. Sand for building purposes is mainly extracted in the southern North Sea, gravel along the English east coast and Channel, shell in the Wadden Sea (North Sea) area of the Netherlands, West Germany and Denmark. Intensive maintenance dredging is carried out along the American east coast and in the southern North Sea (estuaries of the rivers Rhine, Scheldt and Meuse). At present, the short term environmental impact of aggregate extraction activities is small. However, the dumping of polluted harbour dredgings from the ports of Rotterdam and New York is already causing problems. Conflicts might arise with fisheries interest from gravel extraction in the North Sea, where in heavily dredged areas there may be a permanent shift in the species composition of the benthic fauna