Since then the science has evolved from a crude form of conjecture to a fairly accurate predictive one.
This paper prepares a report form of investigation in which the implications of converting hydrographic surveying based on single-beam echo sounders to multiple-beam ones shall be studied and considered in detail to assess feasibility and functional efficacy with particular reference to Medway Ports, UK. To initiate this noble venture it is first necessary to study a little of Medway Port, Kent, UK, especially in detail to its known navigation features.
The Medway Ports authorities define the Medway River as one of the principal trade arteries of the United Kingdom with particular utility to the South East of England through which this river flows before ending into the sea strategically near to the English Channel and the North Sea (Overview, Medway Ports, 2007). This proximal position to two main European trade routes, the port's efficient functionality and its easy accessibility to its hinterland by road, rail and water has eventually evolved it into a port of choice for many export and import operators. Cargoes such a fresh produce, forest products, new vehicles and steel and containers pass through it to and fro British soil (Overview, Medway Ports, 2007).
Actually, the Medway Ports authority is a statutory one and is responsible for a 27 mile stretch of water that is a combination of the Medway and Swale rivers. The authority is responsible for maintaining the rivers and for providing and coordinating pilotage and vessel traffic services to ensure safety of all river users including pleasure boat ones (Overview, Medway Ports, 2007). The Ports are mainly a combination of the Sheerness and Chatham docks (Peel Ports Group, Medway Ports, 2007). Britain's first LNG handling terminal was constructed at the Isle of Grain within the Ports complex (Peel Ports Group, Medway Ports, 2007).
Pilotage services provided by the Ports authorities are compulsory for vessels of 50 metres and above in length.
The Medway Conservancy Board has taken over hydrographic surveying of the Medway Ports system from the Royal Navy Hydrographic Inshore Squadron since the 1960s. Presently, it has tow crafts at its service - the 18.9 metre Medway Surveyor that surveys the main reaches of the Medway and the deeper offshore waters and the 6 metre Medway Recorder which surveys the berths and shallower waters. Both vessels have permanently installed echo sounders that can also work as side scan sonar recorders (Hydrographic Service, Medway Navigation Service, 2007). It is assumed that the echo-sounders are all single beam ones.
Hydrographic surveying is undertaken in two types of operational locations - oceanic or relatively deeper offshore waters and relatively shallower inshore waters. As has already been evidenced with Medway Ports, the former locations are usually surveyed by larger survey ships like the Medway Surveyor and the latter locations by smaller