PAPER NO: 91 DREDGED MATERIAL FROM PORT DEVELOPMENTS: A CASE STUDY OF OPTIONS FOR EFFECTIVE ENVIRONMENTAL MANAGEMENT

The disposal of dredged material arising from port expansion to accommodate larger vessel sizes or increased trade can pose significant environmental challenges, because of the large amounts that may be generated over a relatively short space of time. The conventional management option has been that of sea disposal, for which licences are issued by the Department for Environment, Food and Rural Affairs under the Food and Environment Protection (FEP) Act, 1985, following a satisfactory outcome to a risk assessment of the environmental consequences.

This Act also requires consideration of alternative uses and, while sea disposal continues to account for the bulk of dredged material in the UK, an increasing quantity has been directed elsewhere to serve a variety of purposes. In this paper, we reflect this trend by reference to activities associated with recent dredging of the approach channel and port facility at Harwich, on the SE English coast. Dredged material has been employed in a variety of schemes, designed to counter the effects of net erosional regimes in the adjacent Stour and Orwell estuaries, and to replace intertidal habitat as a result of port development. The outcome of ongoing evaluations of the success of these schemes, both by the industry and regulatory interests, will be briefly reviewed.