I.

Introduction

Thames (Roman, Tamesis), river in southern England, the longest and most important river in England. It rises in four headstreams—the Isis (or Windrush), the Churn, the Coln, and the Leach—on the south-eastern slope of the Cotswold Hills, in Gloucestershire, near Cheltenham. The streams converge on Oxford and flow generally south-east to Reading, through a gap in the Chiltern escarpment. The Thames thereafter follows a generally eastern course through London, and a few kilometres below Gravesend it expands into a wide estuary and enters the North Sea. It is about 344 km (215 mi) long. At London Bridge (see London’s Bridges) the width of the river is about 265 m (870 ft); at Woolwich, 448 m (1,470 ft); at Gravesend pier, 732 m (2,400 ft); 5 km (3 mi) below Gravesend, 1,180 m (3,870 ft); at Nore Light, 10 km (6 mi); and at its mouth, between Whitstable and Foulness Point, the estuary is 29 km (18 mi) across.

II.

The Port of London and Docklands

The area designated as the Port of London extends from Teddington Lock, which is about 16 km (10 mi) west of the city and the limit of the tidal water, downriver to the outer limit of the Tongue light vessel, a distance of 150 km (93 mi). Ocean-going vessels navigate to the upper part of the river through Tower Bridge: these are mainly cruise ships. During the 19th century the docks, at the hub of Britain's worldwide trade, made London the world's busiest port. Rapid decline set in after 1945, however, and shipping is now much diminished.

Bulk cargoes of aggregates are shipped by coasters up river as far as Fulham, thus avoiding many lorry loads travelling on the city's roads. In the reverse direction, much of London's domestic rubbish is transported in containers to landfill sites towards the estuary. Cargo handling takes place on about 100 riverside wharves between Deptford and Canvey Island as well as at enclosed docks at Tilbury. On average 52 million tonnes of cargo is handled in the port annually, making it Britain's largest general cargo port.

It has two oil refineries at Shellhaven and Coryton, and the only cane sugar refinery in the United Kingdom at Silvertown near the Thames Flood Barrier. The Ford Motor Company at its Dagenham riverside works manufactured and shipped completed cars to continental Europe by sea (in 2002 the company switched to producing diesel engines). The whole region has been designated as a development area by the government under the title of “Thames Gateway Initiative”.

The London Docklands, in the capital’s East End, have especially declined greatly since the mid-1960s, and the areas closest to the city have been rezoned for housing and commercial development. A Conservative government initiative in the 1980s to regenerate the area led to some business relocation at sites such as Canary Wharf, the construction of Britain’s tallest building, Canada Tower (also known as Canary Wharf Tower), and the redevelopment of riverside warehouses as luxury apartments.

III.

The Thames in London

The part of the river immediately below London Bridge is called the Pool. Two embankments have been formed, one on the northern shore from Blackfriars Bridge to Westminster and one on the southern shore from Westminster Bridge to Vauxhall. Between Hampton Court and the Tower of London the river is crossed by 20 road and 9 rail bridges. The world's first bored tunnel was built under the Thames by Marc and Isambard Kingdom Brunel from 1825 to 1842. The latest road bridge is the QEII Bridge opened by Elizabeth II in 1991. Sited east of the city, it joins the counties of Essex and Kent, and is the north-south link of the M25 London orbital motorway (the Dartford tunnels are the south-north link).

In June 2000 the Millennium Bridge opened, London’s only dedicated pedestrian bridge across the Thames. It was also the first new bridge to be built over the river in the capital for more than 100 years, and connects St Paul's Cathedral to the new Tate Gallery of Modern Art in Southwark. However, the bridge was forced to close the day after it opened due to safety concerns. After proposed modifications were undertaken the bridge reopened in early 2002. In January that year, the first inland emergency lifeboat service in England was launched along the Thames in London, with stations at Chiswick Pier, Gravesend, Teddington, and Tower Pier, and with headquarters at the Thames Barrier.

IV.

History

Interesting archaeological discoveries have been made in the Thames valley, including fossils of seashells and a human skull of the Palaeolithic period. The Roman invading force (see Roman Britain) commanded by Julius Caesar penetrated to the Thames valley in 55 bc, and Caesar named the river Tamesis. The armies of Claudius's invasion in ad 43 are thought to have first forded, and perhaps bridged, the river in the area of today's Westminster Bridge.

At that time the river in this stretch was shallower and approximately twice its current width, with low-lying marshy ground on either side. When the Romans came to develop the settlement as a port and city, however, they chose a site on higher ground with deeper water, about 1.6 km (1 mi) further downstream, the site of today’s London Bridge and, on the north bank, the City of London. From the late 8th century onward the Thames valley was an important route for invading Vikings, penetrating far inland by ship. In the Middle Ages the valley was prosperous, with many famous religious houses and several large towns, including Oxford, Reading, and Windsor.

V.

Environmental Concerns

The Thames has always been the main source of drinking water for the people along its banks and, since the 19th century, for Greater London as a whole. At the same time, the river has been used as the city’s sewage and industrial waste outlet. This problem was first addressed by the sewage system devised by Joseph Bazalgette and built between 1859 and 1875, which diverted all domestic sewage and rainwater in a unified system of drains to outfalls further downriver. Tides delayed the dispersal of the waste, however, and industrial pollution direct into the river continued until by 1949 the Thames in London had become completely devoid of oxygen. Stringent standards on the purity of all effluents have since 1964 raised the quality of Thames water.

By 1974, when the Port of London Authority handed over pollution control to the new Thames Water Authority, 82 species of freshwater and sea fish were to be found in waters previously inhabited only by the occasional eel. By the year 2000, this had increased to over 100 species.

In 1984 a moveable barrier to protect London from floods caused by extreme high tides and a rising sea level was opened by Elizabeth II at Woolwich. The Thames Flood Barrier consists of six steel gates each weighing up to 1,500 tonnes that are rotated 90° into position from beneath the water.