The Thames Estuary is where the River Thames meets the waters of the North Sea, in the south-east of Great Britain.
The limits of the estuary have been defined in several ways:
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.
The traditional Thames sailing barge worked in this area, designed to be suitable for the shallow waters in the smaller ports. More recently one of the largest wind farms in the UK has been developed in the estuary, located 8.5 km north of Herne Bay, Kent. The farm contains 30 wind turbines generating a total of 82.4MW of electricity. The much larger 630 MW London Array was inaugurated in 2013.
This area has had several proposed sites for the building of a new airport to supplement, or even to replace Heathrow/Gatwick. In the 1960s Maplin Sands was a contender; in 2002 it was to be at Cliffe, Kent. The new airport would be built on a man-made island in the estuary north of Minster-in-SheppeyThere is also some discussion about the need for a Lower Thames Crossing in order to alleviate traffic congestion at Dartford.
The Thames Estuary is the focal part of the 21st-century toponym, the "Thames Gateway", designated as one of the principal development areas in Southern England.
The appellation Greater Thames Estuaryapplies to the coast and the low-lying lands bordering the estuary itself. These are characterised by the presence of mudflats, low-lying open beaches and salt marshes, namely the North Kent Marshes and the Essex Marshes. Man-made embankments are backed by reclaimed wetland grazing areas, but rising sea levels may make it necessary to temporarily flood some of that land in places at spring tides, to take the pressure off the defences.
There are many smaller estuaries in Essex, including the Rivers Colne, Blackwater and Crouch. Small coastal villages depend on an economy of fishing, boat-building, and yachting.The Isle of Sheppey, the Isle of Grain, Canvey Island, Two Tree Island, Havengore Island, New England Island, Rushley Island, Potton Island, Foulness Island and Mersea Island are part of the coastline.
Where higher land reaches the coast there are some larger settlements, such as Clacton-on-Sea to the north in Essex, Herne Bay, Kent, and the Southend-on-Sea area within the narrower part of the estuary.
|Official name||Thames Estuary and Marshes|
|Designated||5 May 2000|
The River Thames flowing through London is a classic river estuary, with sedimentary deposition restricted through manmade embankments. The district of Teddington a few miles south-west of London's centre marks the boundary between the tidal and non-tidal parts of the Thames, although it is still considered a freshwater river about as far east as Battersea insofar as the average salinity is very low and the fish fauna consists predominantly of freshwater species such as roach, dace, carp, perch, and pike. The Thames Estuary becomes brackish between Battersea and Gravesend, and the diversity of freshwater fish species present is smaller, primarily roach and dace, euryhaline marine species such as flounder, European seabass, mullet, and smelt become much more common. Further east, the salinity increases and the freshwater fish species are completely replaced by euryhaline marine ones, until the river reaches Gravesend, at which point conditions become fully marine and the fish fauna resembles that of the adjacent North Sea and includes both euryhaline and stenohaline marine species. A similar pattern of replacement can be observed with the aquatic plants and invertebrates living in the river.
Joseph Conrad lived in Stanford-le-Hope close to the Essex marshes. His The Mirror of the Sea (1906) contains a memorable description of the area as seen from the Thames. It is also described in the first pages of Conrad's Heart of Darkness , as both the launching place of England's great ships of exploration and colonization and, in ancient times, the site of colonization of the British Isles by the Roman Empire.
The form of speech of many of the people of the area, principally the accents of those from Kent and Essex, is often known as Estuary English. The term is a term for a milder variety of the "London Accent". The spread of Estuary English extends many hundreds of miles outside London and all of the neighbouring home counties around London have residents who moved from London and brought their version of London accents with them leading to interference with the established local accents. The term London Accent is generally avoided as it can have many meanings. Forms of "Estuary English" as a hybrid between Received pronunciation and various London accents can be heard in all of the New Towns, all of the coastal resorts and in the larger cities and towns along the Thames Estuary.
For commercial shipping approaching the Nore and thus London, main deep-water routes were the Princes Channel, the Queens Channel and the South Channel to the south, to a lesser extent the Kings Channel and the Swin to the north. The Swin was used by barges and leisure craft from the Essex rivers, and coasters and colliers from the north east. These channels were made up of natural troughs; Yantlet Channel (Sea Reach), Oaze Deep, Knock John Channel, Black Deep Channel which have been extensively marked. These are separated by slow moving sandbanks with names such as the East and West Barrows, the Nob, the Knock, the John, the Sunk, the Girdler, and the Long sands.
The shallow bottomed barges and coasters would navigate the swatchways at flood tide, and would cross the sand banks at spitways, points where the water was least shallow, and just deep enough at that point of the tide. If they missed the moment they would heave to and wait for the next tide.
Recreational craft are expected use channels most suited to the size of their vessel. When navigating to or from the north they should use the Middle Deep, Swin and Warp. Barrow Deep and Warp. When navigating to or from the south, they should use the Horse and Gore and Four Fathom Channels.
To cross the estuary large vessels used Fisherman's Gat, and small vessels to were expected to use Foulger's Gat.
This table shows, from west to east, the principal navigation lights, buoys and other marks to the north (port) and south (starboard) of the main deep-water channels of the River Thames from Gallions Reach to the Sunk Light Float.The Thames is in IALA region A so port buoys are red and starboard buoys are green.
Thames estuary navigation marks
|Name of navigational mark||South of channel||Channel||North of channel|
|Type||Light||Location coordinate||Type||Light||Location coordinate|
|Margaretness Point (or Tripcock Ness) Light||Lighthouse||Group flashing (2) white 5s||Gallions Reach / Barking Reach||̶||̶||̶|
|Crossness Point Light||Lighthouse||Flashing white 5s||Barking Reach / Halfway Reach||̶||̶||̶|
|Crayfordness Point Light||Lighthouse||Flashing white 5s + fixed||Erith Rands / Long Reach||̶||̶||̶|
|Stone Ness Light||̶||̶||̶||Long Reach / St Clement's Reach||Lighthouse||Flashing green 2.5s|
|Broadness Point Light||Lighthouse||Occulting red 5s||St Clement's or Fiddler's Reach / Northfleet Hope||̶||̶||̶|
|Tilbury Warning Light||̶||̶||̶||Gravesend Reach||Warning light, vessels manoeuvring at Tilbury||Isophase 6s|
|Shornmead Light||Lighthouse||Group flashing (2) white, red 10s||Gravesend Reach / The Lower Hope||̶||̶|
|Ovens||̶||̶||̶||The Lower Hope||Quick flashing green|
|Haven Traffic Warning Lights||Warning light, vessels manoeuvring at Coryton||E||The Lower Hope / Sea Reach||Warning light, vessels manoeuvring at Coryton||White|
|London Gateway||̶||̶||̶||Sea Reach||Buoy|
|Sea Reach No. 7||Port buoy |
|Flashing Red 2.5s||The Yantlet Channel||Yellow pillar buoy||Flashing yellow 2.5s|
|Sea Reach No. 6||Port buoy||Flashing red 5s||Starboard buoy||Flashing green 5s|
|Sea Reach No. 5||Port buoy||Very quick flashing red||Starboard buoy||Very quick flashing Green|
|Sea Reach No. 4||Port buoy||Group flashing (2) red 5s||Starboard buoy||Group flashing (2) green 5s|
|Sea Reach No. 3||Port buoy||Quick flashing red||Starboard buoy||Quick flashing green|
|Sea Reach No. 2||Port buoy||Flashing red 5s||Starboard buoy||Flashing green 5s|
|Sea Reach No. 1||Port buoy||Flashing red 2.5s||Yellow pillar buoy |
|Flashing yellow 2.5s|
|West Oaze||̶||̶||̶||The Oaze Deep||Red & white buoy||Isophase 5s|
|Oaze Bank||̶||̶||̶||Starboard buoy||Quick flashing green|
|Oaze||Yellow pillar buoy||Group flashing (4) Yellow 10s||̶||̶||̶|
|Argus||̶||̶||̶||Yellow pillar buoy yellow ‘X’ topmark||Flashing yellow 2.5s|
|Oaze Deep||̶||̶||̶||Starboard buoy||Group flashing (2) green 5s|
|Knob||Red & white buoy||Isophase 5s||̶||̶||̶|
|SE Mouse||̶||̶||̶||Starboard buoy||Quick flashing green|
|Knock John No. 7||̶||̶||̶||The Knock John Channel||Starboard buoy||Group flashing (4) green 15s|
|Knock John No. 5||̶||̶||̶||Starboard buoy||Group flashing (3) green 10s|
|Knock John No. 4||Port buoy||Group flashing (3) red 10s||̶||̶||̶|
|Knock John No. 3||̶||̶||̶||Starboard buoy||Flashing green 5s|
|Knock John No. 2||Port buoy||Flashing red 5s||̶||̶||̶|
|Knock John No. 1||̶||̶||̶||South cardinal buoy||Quick flashing white (6) + long flash 15s|
|Knock John||Port buoy||Group flashing (2) red 5s||̶||̶||̶|
|Black Deep No. 12||Port buoy||Group flashing (4) red 15s||The Black Deep Channel||̶||̶||̶|
|Black Deep No. 11||̶||̶||̶||Starboard buoy||Group flashing (3) green 10s|
|Black Deep No. 10||Port buoy||Group flashing (3) red 10s||̶||̶||̶|
|Black Deep No. 9||̶||̶||̶||South cardinal buoy||Quick flashing white (6) + long flash|
|Inner Fisherman||Port buoy||Quick flashing red||̶||̶||̶|
|Black Deep No. 7||̶||̶||̶||Starboard buoy||Quick flashing green|
|Black Deep No. 8||̶||̶||̶||West cardinal buoy||Quick flashing white (9) 15s|
|BDM2||Yellow pillar buoy (mid-channel)||Flashing yellow 2.5s||̶||̶||̶|
|Black Deep No. 6||Port buoy||Flashing red 2.5s||̶||̶||̶|
|Black Deep No. 5||̶||̶||̶||East cardinal buoy||Very quick flashing white (3) 5s|
|Black Deep No. 4||Port buoy||Group flashing (2) red 5s||̶||̶||̶|
|BDM1||Yellow pillar buoy (mid-channel) yellow ‘X’ topmark||Flashing yellow 2.5s||̶||̶||̶|
|Black Deep No. 3||̶||̶||̶||Starboard buoy||Group flashing (3) green 15s|
|Black Deep No. 1||̶||̶||̶||Starboard buoy||Flashing green 5s|
|Black Deep No. 2||Port buoy||Group flashing (4) red 15s||̶||̶||̶|
|SHM||Yellow pillar buoy (mid-channel) yellow ‘X’ topmark Racon T||Flashing yellow 2.5s||̶||̶||̶|
|Sunk Head Tower||̶||̶||̶||North cardinal buoy||Quick flashing white|
|Black Deep||Port buoy||Quick flashing red||̶||̶||̶|
|Trinity||South cardinal buoy||Quick flashing (6) + long flash 15s||̶||̶||̶|
|Dynamo||̶||̶||̶||Yellow pillar buoy yellow ‘X’ topmark||Flashing yellow 2.5s|
|Sunk Inner||̶||̶||̶||Light float||Isophase 3s|
Brackish water, also sometimes termed brack water, is water occurring in a natural environment having more salinity than freshwater, but not as much as seawater. It may result from mixing seawater with fresh water together, as in estuaries, or it may occur in brackish fossil aquifers. The word comes from the Middle Dutch root "brak". Certain human activities can produce brackish water, in particular civil engineering projects such as dikes and the flooding of coastal marshland to produce brackish water pools for freshwater prawn farming. Brackish water is also the primary waste product of the salinity gradient power process. Because brackish water is hostile to the growth of most terrestrial plant species, without appropriate management it is damaging to the environment.
The River Thames, known alternatively in parts as the River Isis, is a river that flows through southern England including London. At 215 miles (346 km), it is the longest river entirely in England and the second-longest in the United Kingdom, after the River Severn.
The history of lightvessels in the United Kingdom goes back over 250 years. This page also gives a list of lightvessel stations within the United Kingdom, the Channel Islands and Gibraltar.
The Isle of Sheppey is an island off the northern coast of Kent, England, neighbouring the Thames Estuary, centred 42 miles (68 km) from central London. It has an area of 36 square miles (93 km2). The island forms part of the local government district of Swale. Sheppey is derived from Old English Sceapig, meaning "Sheep Island".
Poole Harbour is a large natural harbour in Dorset, southern England, with the town of Poole on its shores. The harbour is a drowned valley (ria) formed at the end of the last ice age and is the estuary of several rivers, the largest being the Frome. The harbour has a long history of human settlement stretching to pre-Roman times. The harbour is extremely shallow, with one main dredged channel through the harbour, from the mouth to Holes Bay.
The Port of London Authority (PLA) is a self-funding public trust established on 31 March 1909 in accordance with the Port of London Act 1908 to govern the Port of London. Its responsibility extends over the Tideway of the River Thames and its continuation. It maintains and supervises navigation, and protects the river's environment.
Queenborough is a small town on the Isle of Sheppey in the Swale borough of Kent in South East England.
Isle of Grain is a village and the easternmost point of the Hoo Peninsula within the district of Medway in Kent. No longer an island and now forming part of the peninsula, the area is almost all marshland and is a major habitat for diverse wetland birds. The village constitutes a civil parish, which at the 2011 census had a population of 1,648, a net decrease of 83 people in 10 years.
A tidal island is a piece of land that is connected to the mainland by a natural or man-made causeway that is exposed at low tide and submerged at high tide. Because of the mystique surrounding tidal islands, many of them have been sites of religious worship, such as Mont-Saint-Michel with its Benedictine Abbey. Tidal islands are also commonly the sites of fortresses because of their natural fortifications.
The Swale is a tidal channel of the Thames estuary that separates the Isle of Sheppey from the rest of Kent. On its banks is a 6,509.4-hectare (16,085-acre) biological Site of Special Scientific Interest which stretches from Sittingbourne to Whitstable in Kent. It is also a Ramsar internationally important wetland site and a Special Protection Area under the European Union Directive on the Conservation of Wild Birds. Parts of it are a Nature Conservation Review site, Grade I, National Nature Reserves, a Kent Wildlife Trust nature reserve and a Local Nature Reserve.
The Nore is a sandbank at the mouth of the Thames Estuary, England. It marks the point where the River Thames meets the North Sea, roughly halfway between Havengore Creek in Essex and Warden Point on the Isle of Sheppey in Kent.
The Tideway is that part of the River Thames in England which is subject to tides. This stretch of water is downstream from Teddington Lock. The Tideway includes the Thames Estuary, the Thames Gateway and the Pool of London.
Chiswick Eyot is a 3.266-acre (1.3 ha) narrow, uninhabited ait in the River Thames. It is a tree- and reed-covered rise on the Tideway by Chiswick, in the Borough of Hounslow, London, England and is overlooked by St Nicholas Church, Chiswick, the Mall of Hammersmith and by some of the Barnes riverside on the far bank. Excluding tidal mudflats and sandbanks, it is the most downstream island purely on the Thames itself.
The River Roach is a river that flows entirely through the English county of Essex. It is one of four main streams that originate in the Rayleigh Hills to the west, and flow east. They then flow towards the centre of the Rochford Basin, a circular feature which may have been caused by an asteroid impact in the Late Oligocene or Early Miocene periods. To the east of Rochford, the river becomes tidal, and is governed by the Crouch Harbour Authority. It joins the River Crouch between Wallasea Island and Foulness Island. To the west of Rochford, there is some doubt as to which of the four streams is officially the Roach.
Grazing marsh is a British Isles term for flat, marshy grassland in polders. It consists of large grass fields separated by fresh or brackish ditches, and is often important for its wildlife.
The Black Deep is a channel which forms the most important of the three main permanent shipping routes past the shoals in the North Sea and outer Thames Estuary, the others being the Barrow Deep and Princes Channel.
The geology of Kent in southeast England largely consists of a succession of northward dipping late Mesozoic and Cenozoic sedimentary rocks overlain by a suite of unconsolidated deposits of more recent origin.
Deadman's Island is a small island in the estuary of the River Medway in Kent, United Kingdom close to where The Swale flows into the Medway. It is a flat, raised area of marshland around 1,200 metres (3,900 ft) long and 200 metres (660 ft) wide among the tidal sand banks on the southern side of the estuary and separated from the British mainland of Chetney Marshes by a narrow channel known as Shepherd's Creek. The town of Queenborough lies around one kilometre (0.62 mi) to the east across the West Swale channel. The island is crossed by several narrow tidal channels that mean that at high tide the island is separated into several smaller islands.
The Swin is a passage in the Thames estuary between Maplin Sands, Foulness Sand and Gunfleet Sand to the north and the Barrow and Sunk sand ridges to the south. The Swin was used by barges and leisure craft from the Essex rivers, and coasters and colliers from the north east.
George Smeed is a Thames barge built in 1882 by Smeed Dean & Co. Ltd. in Murston.