River in south England, flowing through London; length 338 km/210 mi. The longest river in England, it rises in the Cotswold Hills above Cirencester and is tidal as far as Teddington. Below London there is protection from flooding by means of the Thames Barrier (1982). The headstreams unite at Lechlade.
Tributaries from the north are the Windrush, Evenlode, Cherwell, Thame, Colne, Lea, and Roding; and from the south, the Kennet, Loddon, Wey, Mole, Darent, and Medway. Around Oxford the river is sometimes called the Isis.
Source, course, and estuary The Thames rises near Cirencester in the Cotswold Hills and follows a course of 330 km/205 mi to the Nore, where it flows into the North Sea. At Gravesend, the head of the estuary, it has a width of 1 km/0.6 mi, gradually increasing to 16 km/10 mi at the Nore. Lying some 5 km/3 mi southwest of the Nore is the mouth of the Medway estuary, at the head of which lie Chatham with important naval dockyards, Gillingham, and Rochester. Gravesend on the south bank of the river, some 40 km/25 mi from the Nore, developed at a point where vessels used to await the turn of the tide. Tidal waters reach Teddington, 100 km/62 mi from its mouth, where the first lock from the sea (except for the tidal lock at Richmond) is located. There are in all 47 locks, St John's Lock, Lechlade, being nearest the source.
The London Thames The normal rise and fall of the tide is from 4.5 m/15 ft to 7 m/23 ft at London Bridge and from 4 m/13 ft to 6 m/20 ft at Tilbury. Until Tower Bridge was built, London Bridge was the lowest in the course; the reach between these two bridges is known as the ‘Pool of London’. Tilbury, Fort and Docks, important as the main London container terminal, lies opposite Gravesend on the northern bank. At Woolwich, some 30 km/19 mi above Tilbury, is the arsenal; Greenwich, a little farther upriver, has the Royal Naval College. Between Tilbury and London Bridge (some 40 km/25 mi upstream) stretches the London dock System (see also Docklands. The Thames has been frozen over at various times, the earliest recorded occasion being AD 1150.
The embankments of the Thames in London were the work of Joseph Bazalgette (1819–1891), chief engineer of the Metropolitan Board of Works. The Albert Embankment on the south side was completed in 1869, the Victoria Embankment from Westminster to Blackfriars in 1870, and the Chelsea Embankment from the Royal Hospital to Battersea Bridge in 1874. In January 1949 work was started on a new embankment, designed by J Rawlinson, chief engineer of the former London County Council, on the south side from County Hall to Waterloo Bridge. These embankments were raised after 1974. There are walkways (formerly towpaths) from Teddington to Cricklade. The south bank of the river now hosts a number of attractions including the London Eye, the South Bank Centre, Oxo Tower Wharf, the National Theatre, the Tate Modern, and the Globe Theatre. This stretch of the river bank is now largely pedestrianized and has been transformed into a thriving public space.
The Port of London Authority is responsible for the control and conservation of the river below Teddington. There are more than 26,000 commercial vessel movements per year handled by the authority. Above Teddington the the working group Thames Ahead, part of the Environment Agency, is the responsible authority; there is some barge traffic on this stretch of the river. The Thames is of great importance to the water supply of London, partly because the many springs in the chalk usually maintain a steady flow in summer. Salmon returned to the Thames in 1974, showing evidence of improved water quality. The biggest pollution threat is from sewage due to flooding. An 11-km/7-mi flood alleviation channel between Maidenhead and Eton was completed in 2002.
London bridges Archaeological evidence of Bronze and Iron Age bridges has been unearthed. Today the river is spanned by 20 road and 9 rail bridges between Hampton Court and the Tower of London. These include Tower Bridge (which has a drawbridge mechanism to enable large vessels to pass)and a suspension bridge at Hammersmith. The Queen Elizabeth II Bridge, opened in 1991, joins the counties of Essex and Kent. The Millennium Bridge, a footbridge linking St Paul's Cathedral to the new Tate Gallery on the south bank of the Thames, was opened on 10 June 2000; its designers were sculptor Anthony Caro and architect Norman Foster. However it was closed on 12 June 2000 due to greater than expected movement of the bridge while under heavy usage, and was reopened in February 2002 after dampers were fitted. A pedestrian footbridge was opened at Hungerford in May 2002.
London tunnels The chief tunnels under the Thames are the Thames Tunnel, completed by Marc Isambard Brunel in 1843, now used by the East London Line of the London Underground; the Blackwall Tunnel (1897) from East India Dock Road to East Greenwich, the Rotherhithe Tunnel (1918) from Shadwell to Rotherhithe, and the Dartford tunnel completed in 1963.
Upstream There are regular boats from Kingston to Folly Bridge, Oxford, during the summer. There is some beautiful scenery along this part of the river, for example at Cliveden, Cookham, Sonning, and Pangbourne. There are fine bridges at Richmond, Hampton Court, Chertsey, Maidenhead, and Shillingford. Henley, Wallingford, Dorchester, Abingdon, Eton, and Windsor are attractive. Along the 80 km/50 mi from its source beneath a tree in ‘Trewsbury Mead’ to Oxford, the Thames glides through meadows, its course interrupted only by the small towns of Lechlade and Cricklade and the pretty stone-built hamlets of Kelmscott and Ashton Keynes. In these upper reaches there are two medieval bridges, New Bridge and Radcot Bridge. Motor launches can reach Lechlade; beyond that point it is possible to canoe up to Cricklade, but the final 16 km/10 mi to the source of the Thames is best done on foot. One particularly attractive section is the steep-sided valley through the chalk hills between Goring and Reading, known as the Goring Gap.
The Thames Barrier The Thames Barrier at Woolwich was completed in 1982. It is 520 m/1,706 ft long, with steel gates 20 m/66 ft high. When closed, it would prevent the flooding of London.
Tower Bridge raised
The conservancy belonged, but was scarcely exercised by the Crown until 1389 when it was conferred below Staines upon the Mayor or Warden (as...
1 anc. Tamesis \ta-mə-sis\ or Tamesa \-sə\. River, SE Connecticut; actually a tidal estuary formed by confluence of...