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Tideway

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A tidal river is a river whose flow and level are caused by tides . A section of a larger river affected by the tides is a tidal reach , but it may sometimes be considered a tidal river if it had been given a separate and another title name.

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76-564: The Tideway is the part of the River Thames in England which is subject to tides . This stretch of water is downstream from Teddington Lock . The Tideway comprises the upper Thames Estuary including the Pool of London . Depending on the time of year, the river tide rises and falls twice a day by up to 7 m (24 ft). Because the tide goes against the outflow of fresh water from

152-435: A "river reach." In terms of tides, tidal rivers are classified as microtidal (<2 m), mesotidal (2-4 m), and macrotidal (>4 m). Areas of brackish water seaward of the tidal river section are often called estuaries . A phenomenon commonly associated with tidal rivers is a tidal bore , where a wall of water travels upriver during a flood tide. Freshwater tidal rivers discharge large amounts of sediment and nutrients into

228-561: A network of creeks. Lying below sea level, it is prone to flooding at exceptional tides, but has nevertheless been inhabited since Roman times. The usually quoted source of the Thames is at Thames Head (at grid reference ST980994 ). This is about 1.5 mi (2.4 km) north of the village of Kemble in southern Gloucestershire , near the town of Cirencester , in the Cotswolds . However, Seven Springs near Cheltenham , where

304-474: A shallow river with a large coastal mouth. In some cases, high tides impound downstream flowing freshwater, reversing the flow and increasing the water level of the lower section of river, forming large estuaries . High tides can be noticed as far as 100 kilometres (62 mi) upstream. Oregon's Coquille River is one such stream for which that effect can be noticed. The area of a tidal river can be difficult to define. The term "tidal river" generally encompasses

380-507: A small part of western England; the river is fed by at least 50 named tributaries . The river contains over 80 islands . With its waters varying from freshwater to almost seawater, the Thames supports a variety of wildlife and has a number of adjoining Sites of Special Scientific Interest , with the largest being in the North Kent Marshes and covering 20.4 sq mi (5,289 ha). According to Mallory and Adams,

456-639: A summer venue for organised swimming, which is prohibited on safety grounds in a stretch centred on Central London . After the river took its present-day course, many of the banks of the Thames Estuary and the Thames Valley in London were partly covered in marshland , as was the adjoining Lower Lea Valley . Streams and rivers like the River Lea , Tyburn Brook and Bollo Brook drained into

532-471: Is a landmark on the Boat Race course, while Glover's Island forms the centre of a view from Richmond Hill . Islands of historical interest include Magna Carta Island at Runnymede , Fry's Island at Reading, and Pharaoh's Island near Shepperton. In more recent times Platts Eyot at Hampton was the place where Motor Torpedo Boats (MTB)s were built, Tagg's Island near Molesey was associated with

608-600: Is a speed limit of 8 knots (15 km/h) west of Wandsworth Bridge and in tributary creeks, and except for authorised vehicles, 12 knots (22 km/h) between Wandsworth Bridge and Margaretness. The tidal river is used for leisure navigation. In London sections there are many sightseeing tours in tourist boats past riverside attractions such as the Houses of Parliament and the Tower of London , as well as regular riverboat services provided by London River Services . This section

684-402: Is an important water source, especially in the drier months, so maintaining its quality and quantity is extremely important. Groundwater is vulnerable to surface pollution, especially in highly urbanised areas. Brooks, canals and rivers, within an area of 3,842 sq mi (9,951 km ), combine to form 38 main tributaries feeding the Thames between its source and Teddington Lock . This

760-649: Is believed that Tamesubugus' name was derived from that of the river. Tamese was referred to as a place, not a river in the Ravenna Cosmography ( c.  AD 700 ). The river's name has always been pronounced with a simple t /t/ ; the Middle English spelling was typically Temese and the Brittonic form Tamesis . A similar spelling from 1210, "Tamisiam" (the accusative case of "Tamisia"; see Kingston upon Thames § Early history ),

836-604: Is formed for much of its length for shipping and supplies: through the Port of London for international trade, internally along its length and by its connection to the British canal system. The river's position has put it at the centre of many events in British history, leading to it being described by John Burns as "liquid history". Two broad canals link the river to other rivers: the Kennet and Avon Canal ( Reading to Bath ) and

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912-697: Is found in Magna Carta . The Thames through Oxford is sometimes called the Isis . Historically, and especially in Victorian times, gazetteers and cartographers insisted that the entire river was correctly named the Isis from its source down to Dorchester on Thames and that only from this point, where the river meets the Thame and becomes the "Thame-isis" (supposedly subsequently abbreviated to Thames) should it be so called. Ordnance Survey maps still label

988-456: Is not suitable for sporting activity because of the strong stream through the bridges. Rowing has a significant presence upstream of Putney Bridge, while sailing takes place in the same area and also along the coasts of the Estuary. The annual Great River Race for traditional rowed craft takes place over the stretch from Greenwich to Ham . Thames meander challenges along the length of

1064-452: Is responsible for managing the flow of water to help prevent and mitigate flooding, and providing for navigation: the volume and speed of water downstream is managed by adjusting the sluices at each of the weirs and, at peak high water, levels are generally dissipated over preferred flood plains adjacent to the river. Occasionally, flooding of inhabited areas is unavoidable and the agency issues flood warnings. Due to stiff penalties applicable on

1140-948: Is shared by many other river names in Britain, such as the River Tamar at the border of Devon and Cornwall , several rivers named Tame in the Midlands and North Yorkshire , the Tavy on Dartmoor , the Team of the North East, the Teifi and Teme of Wales , the Teviot in the Scottish Borders and a Thames tributary, the Thame . Kenneth H. Jackson proposed that the name of

1216-772: Is the longest river entirely in England and the second-longest in the United Kingdom , after the River Severn . The river rises at Thames Head in Gloucestershire and flows into the North Sea near Tilbury , Essex and Gravesend , Kent, via the Thames Estuary . From the west, it flows through Oxford (where it is sometimes called the Isis), Reading , Henley-on-Thames and Windsor . The Thames also drains

1292-404: Is the usual tidal limit ; however, high spring tides can raise the head water level in the reach above Teddington and can occasionally reverse the river flow for a short time. In these circumstances, tidal effects can be observed upstream to the next lock beside Molesey weir , which is visible from the towpath and bridge beside Hampton Court Palace . Before Teddington Lock was built in 1810–12,

1368-403: Is visited occasionally by cruise ships or warships , which moor alongside HMS Belfast , and a few smaller aggregate or refuse vessels, operating from wharves in the west of London. Most trade is handled by the Port of Tilbury , roll-on/roll-off ferry terminals at Dagenham and Dartford , and petroleum products handling facilities at Purfleet , Coryton and Canvey Island . There

1444-811: The Berwyn Mountains in North Wales . About 450,000 years ago, in the most extreme Ice Age of the Pleistocene , the Anglian , the furthest southern extent of the ice sheet reached Hornchurch in east London, the Vale of St Albans, and the Finchley Gap . It dammed the river in Hertfordshire , resulting in the formation of large ice lakes, which eventually burst their banks and caused

1520-541: The British Geological Survey from the banks of the tidal River Thames contain geochemical information and fossils which provide a 10,000-year record of sea-level change. Combined, this and other studies suggest that the Thames sea-level has risen more than 30 m during the Holocene at a rate of around 5–6 mm per year from 10,000 to 6,000 years ago. The rise of sea level dramatically reduced when

1596-570: The Churn (which feeds into the Thames near Cricklade ) rises, is also sometimes quoted as the Thames' source, as this location is farthest from the mouth and adds some 14 mi (23 km) to the river's length. At Seven Springs above the source is a stone with the Latin hexameter inscription "Hic tuus o Tamesine pater septemgeminus fons", which means "Here, O Father Thames, [is] your sevenfold source". The springs at Seven Springs flow throughout

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1672-684: The Grand Union Canal (London to the Midlands). The Grand Union effectively bypassed the earlier, narrow and winding Oxford Canal which remains open as a popular scenic recreational route. Three further cross-basin canals are disused but are in various stages of reconstruction: the Thames and Severn Canal (via Stroud ), which operated until 1927 (to the west coast of England), the Wey and Arun Canal to Littlehampton , which operated until 1871 (to

1748-867: The Port of London Authority (PLA). The upstream limit of this authority is marked by an obelisk just short of Teddington Lock and to seaward by the London Stone at Yantlet Creek. The PLA is responsible for one lock on the Thames: Richmond Lock . Within Greater London, the Tideway is secured by the Metropolitan Police Marine Policing Unit . East of Crayford Ness, Essex Police and Kent Police assume responsibility in their respective jurisdictions. 21st-century criminal investigations have included

1824-489: The River Lea can be considered another boundary. Most of the local riverside was also marshland. The land was drained and became farmland; it was built on after the Industrial Revolution . Canvey Island in southern Essex (area 18.45 km , 7.12 sq mi; population 40,000 ) was once marshy, but is now a fully reclaimed island in the Thames estuary, separated from the mainland of south Essex by

1900-745: The Roberto Calvi and Torso in the Thames cases. London Fire Brigade maintains a fire boat on the river in central London. As a result of the Marchioness disaster in 1989, when 51 people died, the Government asked the Maritime and Coastguard Agency , the Port of London Authority , and the Royal National Lifeboat Institution (RNLI) to work together to set up a dedicated Search and Rescue service for

1976-662: The Royal Academy , London , in 1785. They are now on show at the River and Rowing Museum in Henley). Richard Coates suggests that while the river was as a whole called the Thames, part of it, where it was too wide to ford, was called * (p)lowonida . This gave the name to a settlement on its banks, which became known as Londinium , from the Indo-European roots * pleu- "flow" and * -nedi "river" meaning something like

2052-504: The Thames Barrier , which protects central London from flooding by storm surges . Below the barrier, the river passes Woolwich , Thamesmead , Dagenham , Erith , Purfleet , Dartford , West Thurrock , Northfleet , Tilbury and Gravesend before entering the Thames Estuary near Southend-on-Sea . The sea level in the Thames estuary is rising and the rate of rise is increasing. Sediment cores up to 10 m deep collected by

2128-482: The Thames Basin , it takes longer to subside (6–9 hours) than it does to flow in (4–5 hours). London Bridge is used as the basis for published tide tables giving the times of high tide . High tide reaches Putney about 30 minutes later. Low-lying banks of London are naturally vulnerable to flooding by storm surges . The threat has increased due to a slow but continuous rise in high water level, caused by

2204-549: The Thanetian stage of the late Palaeocene epoch. Until around 500,000 years ago, the Thames flowed on its existing course through what is now Oxfordshire , before turning to the north-east through Hertfordshire and East Anglia and reaching the North Sea near present-day Ipswich . At this time the river-system headwaters lay in the English West Midlands and may, at times, have received drainage from

2280-766: The Greater Thames Estuary and is one of the largest inlets on the coast of Great Britain . The water can rise by 4 metres moving at a speed of 8 miles per hour. The estuary extends into London near Tower Bridge, and can be divided into the Outer Estuary up to the Swale at the west end of the Isle of Sheppey , and the Inner Estuary, designated the Thames Gateway above this point. The shore of

2356-686: The North Sea, and the Thames Barrier was built in the 1980s to protect London from this risk. The Nore is the sandbank that marks the mouth of the Thames Estuary , where the outflow from the Thames meets the North Sea . It is roughly halfway between Havengore Creek in Essex and Warden Point on the Isle of Sheppey in Kent. Until 1964 it marked the seaward limit of the Port of London Authority. As

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2432-546: The Outer Estuary consists of saltmarshes and mudflats, but there are manmade embankments along much of the route. Behind these, the land is cultivated or used for grazing. Parts of the Outer Estuary are on a major shipping route. The Gateway is some 70 kilometres (43 mi) long, stretching from the Isle of Sheppey to Limehouse in Tower Hamlets . Its boundary was drawn to capture the riverside strip that formerly hosted many land extensive industries, serving London and

2508-550: The River Thames on the Tideway include the rivers Crane , Brent , Wandle , Ravensbourne (the final part of which is called Deptford Creek ), Lea (the final part of which is called Bow Creek ), Roding (Barking Creek), Darent and Ingrebourne . In London, the water is slightly brackish with sea salt, being a mix of sea and fresh water. This part of the river is managed by the Port of London Authority . The flood threat here comes from high tides and strong winds from

2584-779: The South East. The decline of these industries has left a legacy of large scale dereliction and contaminated land , but an opportunity for major redevelopment. The area includes the London Docklands , Millennium Dome , London Riverside and Thames Barrier . The Pool of London is divided into two parts, the Lower Pool and Upper Pool. The Lower Pool traditionally runs from the Cherry Garden Pier in Rotherhithe to Tower Bridge . The Upper Pool consists of

2660-480: The Thames Estuary), the river is subject to tidal activity from the North Sea . Before the lock was installed, the river was tidal as far as Staines, about 16 mi (26 km) upstream. London, capital of Roman Britain , was established on two hills, now known as Cornhill and Ludgate Hill . These provided a firm base for a trading centre at the lowest possible point on the Thames. A river crossing

2736-521: The Thames as "River Thames or Isis" down to Dorchester. Since the early 20th century this distinction has been lost in common usage outside of Oxford, and some historians suggest the name Isis is nothing more than a truncation of Tamesis , the Latin name for the Thames. Sculptures titled Tamesis and Isis by Anne Seymour Damer are located on the bridge at Henley-on-Thames , Oxfordshire (the original terracotta and plaster models were exhibited at

2812-636: The Thames due to the introduction of shipping containers and coastal deep-water ports in the 1960s emptied the Pool and led to all of the wharves being closed down. The Lower Pool area was extensively redeveloped in the 1980s and 1990s to create new residential and commercial neighbourhoods, often using converted warehouses. In the Upper Pool this provided scope for office development in the City of London and Southwark . Between London Bridge and Putney Bridge ,

2888-523: The Thames from Lechlade often pass through the London sections and finish well downstream, for example at Gravesend Pier. The Grand Union Canal joins the river at Brentford , with a branch – the Regent's Canal – joining at Limehouse Basin . The other part of the canal network still connecting on the Tideway is the River Lea Navigation via Bow Lock . Narrow low-lying belts beside

2964-493: The Thames is not Indo-European (and of unknown meaning), while Peter Kitson suggested that it is Indo-European but originated before the Britons and has a name indicating "muddiness" from a root *tā- , 'melt'. Early variants of the name include: Indirect evidence for the antiquity of the name "Thames" is provided by a Roman potsherd found at Oxford, bearing the inscription Tamesubugus fecit (Tamesubugus made [this]). It

3040-423: The Thames' discharge is low considering its length and breadth: the Severn has a discharge almost twice as large on average despite having a smaller drainage basin . In Scotland , the Tay achieves more than double the Thames' average discharge from a drainage basin that is 60% smaller. Along its course are 45 navigation locks with accompanying weirs . Its catchment area covers a large part of south-eastern and

3116-511: The Thames, from Middle English Temese , is derived from the Brittonic name for the river, Tamesas (from * tamēssa ), recorded in Latin as Tamesis and yielding modern Welsh Tafwys "Thames". The name element Tam may have meant "dark" and can be compared to other cognates such as Russian темно ( Proto-Slavic * tĭmĭnŭ ), Lithuanian tamsi "dark", Latvian tumsa "darkness", Sanskrit tamas and Welsh tywyll "darkness" and Middle Irish teimen "dark grey". The origin

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3192-481: The Tideway is home to most of London's rowing clubs, and is the venue for training and racing throughout the year. The Championship Course over which The Boat Race and many other events are run, stretches from Putney to Mortlake. River Thames The River Thames ( / t ɛ m z / TEMZ ), known alternatively in parts as the River Isis , is a river that flows through southern England including London . At 215 miles (346 km), it

3268-487: The Tideway is still poor. Heavier rainfall in London causes overflows from pipes on the river banks from the standard type of sewer in the capital, the combined sewer . Around 39,000,000 m (3.9 × 10 L) or 39 million tonnes of untreated sewage mixed with rainwater are released into the Tideway each year from sewage treatment works and combined sewer overflows (CSOs), averaging 106,849 m (106,849,000 L) per day or 106,849 tonnes per day. These CSOs can cause

3344-411: The area upriver of the maximum limit of salinity intrusion and downriver of tidal water level fluctuations. This classification is based on both tidal trends and salinity. By this definition, a tidal river will be affected by tides, surges, and sea level variation, though its water may not have a high salinity content. If that is the case, this section of river can be known as a "tidal freshwater river" or

3420-423: The case of the Colne ), and man-made distributaries such as the Longford River . Three canals intersect this stretch: the Oxford Canal , Kennet and Avon Canal and Wey Navigation . Its longest artificial secondary channel (cut), the Jubilee River , was built between Maidenhead and Windsor for flood relief and completed in 2002. The non-tidal section of the river is managed by the Environment Agency , which

3496-423: The confluence, the overall length of the Thames measured from Seven Springs, at 229 mi (369 km), is greater than the Severn's length of 220 mi (350 km). Thus, the "Churn/Thames" river may be regarded as the longest natural river in the United Kingdom. The stream from Seven Springs is joined at Coberley by a longer tributary which could further increase the length of the Thames, with its source in

3572-403: The deaths of marine life and health hazards for river users. The Thames Tideway Scheme , under construction, aims to divert most of the overflow from sewers into a tunnel under the river. The Thames Estuary is bordered by the coast and the low-lying lands upstream between the mouth of the River Stour on the Essex / Suffolk border and The Swale in north Kent . It is now usually designated

3648-403: The extremely slow 'tilting' of Britain (up in the north and down in the south) due to post-glacial rebound and the gradual rise in sea levels due to climate change. The city and state have erected defensive barriers, including the Thames Barrier , which was constructed across the Thames at Woolwich to deal with this threat. The Tideway, often referred to as the Port of London , is managed by

3724-412: The flowing river or the wide flowing unfordable river. The river gives its name to three informal areas: the Thames Valley , a region of England around the river between Oxford and West London; the Thames Gateway ; and the greatly overlapping Thames Estuary around the tidal Thames to the east of London and including the waterway itself. Thames Valley Police is a formal body that takes its name from

3800-533: The grounds of the National Star College at Ullenwood . The Thames flows through or alongside Ashton Keynes , Cricklade , Lechlade , Oxford , Abingdon-on-Thames , Wallingford , Goring-on-Thames and Streatley (at the Goring Gap ), Pangbourne and Whitchurch-on-Thames , Reading , Wargrave , Henley-on-Thames , Marlow , Maidenhead , Windsor and Eton , Staines-upon-Thames and Egham , Chertsey , Shepperton , Weybridge , Sunbury-on-Thames , Walton-on-Thames , Molesey and Thames Ditton . The river

3876-452: The highest flow, largest volume of sediment discharge, and largest drainage basin of any river in the world. Because of its large flow volume, saltwater never enters the mouth of the Amazon River, and the limit of salinity is 150 km seaward of the river mouth. The Amazon River is classified as macrotidal, as its tidal range is 4 to 8 meters at the mouth of the river. During low-flow periods, this river's tidal area may extend over 1,000 km into

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3952-404: The ice melt nearly concluded over the past 4,000 years. Since the beginning of the 20th century, rates of sea level rise range from 1.22 mm per year to 2.14 mm per year. The Thames River Basin District, including the Medway catchment, covers an area of 6,229 sq mi (16,130 km ). The entire river basin is a mixture of urban and rural, with rural landscape predominating in

4028-416: The impresario Fred Karno and Eel Pie Island at Twickenham was the birthplace of the South East's R&B music scene. Westminster Abbey and the Palace of Westminster (commonly known today as the Houses of Parliament ) were built on Thorney Island , which used to be an eyot . Researchers have identified the River Thames as a discrete drainage line flowing as early as 58 million years ago, in

4104-426: The non-tidal river, which is a drinking water source before treatment, sanitary sewer overflow from the many sewage treatment plants covering the upper Thames basin should be rare in the non-tidal Thames. However, storm sewage overflows are still common in almost all the main tributaries of the Thames despite claims by Thames Water to the contrary. Below Teddington Lock (about 55 mi or 89 km upstream of

4180-748: The ocean. This is a necessary influx for the global water balance. Rivers contribute about 95% of sediment entering the ocean. Discharge estimates from freshwater tidal rivers are important for informing water resource management and climate analyses. These discharge amounts can be estimated using tidal statistics. Some challenges to estimating discharge amounts include reversing tidal flow, compensation flow for Stokes drift, spring-neap water storage effects, lateral circulation, and multiple distributaries or ebb and flood channels. Tidal rivers face threats due to climate change and other human-caused impacts. In tidal rivers' deltas, mineral and water extraction, reduced sediment input, and floodplain engineering are causing

4256-466: The risk of flooding. The Rio de la Plata is a tidal river on the border between Uruguay and Argentina . It is classified as microtidal, as its tidal range is less than 1 meter. This river is significant mostly due to its size, as more than one tidal wavelength can be accommodated in this river's estuary. Similarly to most tidal rivers, saltwater does not extend far up the river, due to its large volume of freshwater discharge. The Amazon River has

4332-534: The river passes Pimlico and Vauxhall , and then forms one of the principal axes of the city, from the Palace of Westminster to the Tower of London . At this point, it historically formed the southern boundary of the medieval city, with Southwark , on the opposite bank, then being part of Surrey . Beyond central London, the river passes Bermondsey , Wapping , Shadwell , Limehouse , Rotherhithe , Millwall , Deptford , Greenwich , Cubitt Town , Blackwall , New Charlton and Silvertown , before flowing through

4408-433: The river passes through Central London and some of the most famous landmarks. River boats carry tourists up down and across the river, and also provide a regular commuter service. (culverted tributaries largely converted to sewers are marked ‡) From Putney Bridge to Teddington Lock , the river passes through inner and outer suburbs such as Hammersmith , Chiswick , Barnes , Richmond on Thames and Ham . This part of

4484-514: The river to divert onto its present course through the area of present-day London. The ice lobe which stopped at present-day Finchley deposited about 14 metres of boulder clay there. Its torrent of meltwater gushed through the Finchley Gap and south towards the new course of the Thames, and proceeded to carve out the Brent Valley in the process. Tidal river Generally, tidal rivers are short rivers with relatively low discharge rates but high overall discharge, which generally implies

4560-439: The river was tidal at peak spring tides as far as Staines upon Thames . In descending order, non-related tributaries of the non-tidal Thames, with river status, are the Churn , Leach , Cole , Ray , Coln , Windrush , Evenlode , Cherwell , Ock , Thame , Pang , Kennet , Loddon , Colne , Wey and Mole . In addition, there are occasional backwaters and artificial cuts that form islands, distributaries (most numerous in

4636-530: The river, covering three counties . In non-administrative use, the river's name is used in those of Thames Valley University , Thames Water , Thames Television , publishing company Thames & Hudson , Thameslink (north–south rail service passing through central London ) and South Thames College . An example of its use in the names of historic entities is the Thames Ironworks and Shipbuilding Company . Marks of human activity, in some cases dating back to Pre-Roman Britain , are visible at various points along

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4712-399: The river, while some islands, e.g. Thorney Island , formed over the ages. The northern tip of the ancient parish of Lambeth , for example, was marshland known as Lambeth Marshe , but it was drained in the 18th century; the street names Lower Marsh and Upper Marsh preserve a memory. Until the middle of the Victorian era, malaria was commonplace beside the River Thames, even in London, and

4788-467: The river. These include a variety of structures connected with use of the river, such as navigations, bridges and watermills , as well as prehistoric burial mounds . The lower Thames in the Roman era was a shallow waterway winding through marshes. But centuries of human intervention have transformed it into a deep tidal canal flowing between 200 miles of solid walls; these defend a floodplain where 1.5 million people work and live. A major maritime route

4864-494: The sandbank was a major hazard for shipping coming in and out of London, in 1732 it received the world's first lightship . This became a major landmark, and was used as an assembly point for shipping. Today it is marked by Sea Reach No. 1 Buoy. The River Thames contains over 80 islands ranging from the large estuarial marshlands of the Isle of Sheppey and Canvey Island to small tree-covered islets like Rose Isle in Oxfordshire and Headpile Eyot in Berkshire. They are found all

4940-441: The section between Tower Bridge and London Bridge . In the 18th and 19th centuries the river was lined with nearly continuous walls of wharves running for miles along both banks, and hundreds of ships moored in the river or alongside the quays. The lack of capacity in the Pool of London prompted landowners to build London's Docklands with enclosed docks with better security and facilities. The abrupt collapse of commercial traffic in

5016-452: The sinking of deltas. This, combined with rising sea levels , is causing tidal rivers to become deeper, which amplifies the tidal motion and increases the extent of salt intrusion. Increasing salinity in tidal rivers could have a detrimental impact on freshwater organisms and alter tidal river ecosystems significantly. The increasing effect of deltaic subsidence, which is due to the removal of gas, oil, and water from deltas, will also increase

5092-419: The south coast), and the Wilts & Berks Canal . Rowing and sailing clubs are common along the Thames, which is navigable to such vessels. Kayaking and canoeing also take place. Major annual events include the Henley Royal Regatta and the Boat Race , while the Thames has been used during two Summer Olympic Games : 1908 ( rowing ) and 1948 ( rowing and canoeing ). Safe headwaters and reaches are

5168-417: The tidal River Thames. Since 2002, four lifeboat stations have been established on the Thames, at: Teddington , Chiswick , Tower Pier , and Gravesend . The River is navigable to large ocean-going ships as far as the Pool of London at London Bridge . The Port of London is the United Kingdom's second largest port by tonnage. Today, little commercial traffic passes above the Thames Barrier. Central London

5244-408: The tidal section of the Thames regularly flood at spring tides, supporting brackish plants. One such example is at Chiswick Lane South, where the river, as pictured, overflows this road a few times per year. (Picture taken in 2006). Although water quality has improved over the last 40 years and efforts to clean up the Tideway have led to the reintroduction of marine life and birds, the environment of

5320-652: The way from Fiddler's Island in Oxfordshire to the Isle of Sheppey in Kent. Some of the largest inland islands, for example Formosa Island near Cookham and Andersey Island at Abingdon, were created naturally when the course of the river divided into separate streams. In the Oxford area the river splits into several streams across the floodplain ( Seacourt Stream , Castle Mill Stream , Bulstake Stream and others), creating several islands ( Fiddler's Island , Osney and others). Desborough Island , Ham Island at Old Windsor and Penton Hook Island were artificially created by lock cuts and navigation channels. Chiswick Eyot

5396-412: The western part. The area is among the driest in the United Kingdom. Water resources consist of groundwater from aquifers and water taken from the Thames and its tributaries, much of it stored in large bank-side reservoirs . The Thames itself provides two-thirds of London's drinking water, while groundwater supplies about 40 per cent of public water supplies in the overall catchment area. Groundwater

5472-487: The whole of Greater London . The lower reaches of the river are called the Tideway , derived from its long tidal reach up to Teddington Lock . Its tidal section includes most of its London stretch and has a rise and fall of 23 ft (7 m). From Oxford to the estuary, the Thames drops by 55 metres (180 ft). Running through some of the drier parts of mainland Britain and heavily abstracted for drinking water,

5548-580: The year, while those at Thames Head are seasonal (a winterbourne ). With a length of 215 mi (346 km), the Thames is the longest river entirely in England. (The longest river in the United Kingdom, the Severn , flows partly in Wales .) However, as the River Churn, sourced at Seven Springs, is 14 mi (23 km) longer than the section of the Thames from its traditional source at Thames Head to

5624-479: Was built at the site of London Bridge . London Bridge is now used as the basis for published tide tables giving the times of high tide . High tide reaches Putney about 30 minutes later than London Bridge, and Teddington about an hour later. The tidal stretch of the river is known as "the Tideway ". Tide tables are published by the Port of London Authority and are available online. Times of high and low tides are also posted on Twitter. The principal tributaries of

5700-463: Was frequently lethal. Some cases continued to occur into the early 20th century. Draining of the marshes helped with its eradication, but the causes are complex and unclear. The East End of London , also known simply as the East End , was the area of London east of the medieval walled City of London and north of the River Thames, although it is not defined by universally accepted formal boundaries;

5776-617: Was subject to minor redefining and widening of the main channel around Oxford, Abingdon and Marlow before 1850, when further cuts to ease navigation reduced distances further. Molesey faces Hampton , and in Greater London the Thames passes Hampton Court Palace , Surbiton , Kingston upon Thames , Teddington , Twickenham , Richmond (with a famous view of the Thames from Richmond Hill), Syon House , Kew , Brentford , Chiswick , Barnes , Hammersmith , Fulham , Putney , Wandsworth , Battersea and Chelsea . In central London ,

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