Discussion on Papers 15–17

MR BARRETT, Paper 15

1. The wide spread of subject matter in the Symposium papers illustrates the many interests and requirements which have to be reconciled by the design engineer. I am concerned that many

of the papers and much of the discussion may give the impression that sea walls are no longer an acceptable expedient. While many rigid structures are ill conceived, I submit that hard defences remain an essential option.

2. Unlike the North Sea coastline of mainland Europe, many UK beaches are shallow and are underlain and backed by relatively soft strata comprising fine sediments which, once eroded, are permanently lost to the littoral system. Such materials must be protected against the eventuality of beach draw-down under exceptional storm conditions even though normal beach profiles are adequate. Under these circumstances sea walls are an effective (and often the only practical) expedient. The schemes described in the Paper are illustrated in Figs 1-6.