Thames Estuary

Coordinates: 51°30′N 0°35′E / 51.500°N 0.583°E / 51.500; 0.583

The Thames Estuary is the estuary in which the River Thames meets the waters of the North Sea.

It is not easy to define the limits of the estuary. Although physically the head of Sea Reach or the Kent/Essex Strait, south of Canvey Island on the northern (Essex) shore presents a western boundary, the Tideway itself can be considered estuarine; it starts in south-west London at Teddington/Ham. The eastern boundary of the estuary suggested in a Hydrological Survey of 1882-9 is a line drawn from North Foreland, Margate, Kent via the Kentish Knock lighthouse to Harwich in Essex. It is to this line that the typical estuarine sandbanks extend. The estuary downstream of the Tideway has a tidal movement of 4 metres, moving at a speed of 8 miles per hour.

The estuary is one of the largest of 170 such inlets on the coast of Great Britain. It constitutes a major shipping route: its thousands of movements each year include large oil tankers, container ships, bulk carriers and roll-on/roll-off (ro-ro) ferries entering the estuary for the Port of London and the Medway Ports of Sheerness, Chatham and Thamesport.