There is little doubt that the long term future of port and estuary hydrographic surveying may well lie with multibeam (swath) echo sounding; the big question is, at what point will the present rapid developments in this field allow it to be all things to all men? For some time now, this type of equipment has opened up the possibility of carrying out extensive surveys in deep water and now manufacturers are looking towards extending its capabilities into large-scale shallow water surveying.
With the recent rapid advancements in computer technology, there is no longer a problem in the collection and processing of vast data sets (up to 30,000 data points per second can be produced by a swath multibeam system!) The swath system is also particularly suited to the production of almost 'photographic' views of the seabed and, in addition, because of its large area of view, it can be used in a 'sideways looking' mode to inspect jetties, piers, breakwaters etc. It can also be used a tool to search a large area for wreck location, it has obvious coverage advantages over a conventional echo-sounder, these advantages only previously being equalled by a side-scan sonar.