MaheMir New Song ‘Uska Kharam Dekh Kar’ Released
The River Thames is by far the largest river of the London (place) area, flowing west to east across the London Basin. It is rather larger than would be expected if it only drained the basin, since its headwaters cut into the London basin through the Goring Gap and also drain parts of the Cotswolds and Vale of Aylesbury. Similarly tributaries such as the Mole cut through the North Downs into the basin from the south. Further downstream the flow of the Thames is boosted by springs which open onto the riverbed where this is on chalk.
The Thames was once a much broader, shallower river than it is today. It has been extensively embanked. The Thames is tidal (the Tideway) up to Teddington Lock, and London is vulnerable to flooding by storm surges. The threat has increased over time due to a slow but continuous rise in high water level, caused by both the slow ’tilting’ of Britain (up in the north and down in the south) caused by post-glacial rebound and the gradual rise in sea levels due to climate change. The Thames Barrier was constructed across the Thames at Woolwich in the 1970s to deal with this threat, but in early 2005 it was suggested that a ten mile long barrier further downstream might be required to deal with the flood risk in the future.
Within London a considerable number of rivers and streams flow into the Thames, some large enough to have exerted a significant influence on the geography of the area. Many of the smaller London tributaries now flow underground.
Left bank tributaries
Larger left bank tributaries include the Colne, Crane, Brent, Lea (tidal reach known as ‘Bow Creek’), Roding (tidal reach known as ‘Barking Creek’), Rom (lower reaches known as the Beam) and Ingrebourne. There are many smaller, now often largely subterranean streams including Stamford Brook, Counter’s Creek (also known as ‘Chelsea Creek’), Westbourne, Tyburn, Tyburn Brook, Fleet and Walbrook. Some of the tributaries are themselves large enough to have named tributary streams, for example the Moselle, Salmons Brook and Pymmes Brook that feed the Lea, and the Silk Stream and Dollis Brook that feed the Brent.
Larger rivers such as the Lea have influenced local geography in several ways. Firstly a river and its marshland formed a significant barrier to east-west movement – the Lea formed a natural boundary between the historic areas of Middlesex and Essex. Secondly the valley of the Lea formed a route – both the river and later Lee Navigation, and roads including the Roman Ermine Street, the Hertford Road (A1010) and the later Great Cambridge Road (A10) and A1055. The Lea Valley is also followed by two routes of what became the Great Eastern Railway and had important marshalling yards and locomotive works at Temple Mills. Thirdly the river provided power for numerous water mills well known examples being the Royal Small Arms Factory at Enfield and nearby Waltham Abbey Royal Gunpowder Mills, Wright’s Flour Mill (London’s last surviving working mill) at Ponders End and the Three Mills at Stratford. In the 19th Century the lower Lea became an important area for the manufacture of chemicals, in part based on the supply of by-products such as sulphur and ammonia from the Gas Light and Coke Company’s works at Bow Common. In the 20th Century the combination of transport, wide expanses of flat land and electricity from riverside and canalside plants such as Brimsdown, Hackney, Bow and West Ham led to expansion of industries including for example Enfield Rolling Mills and Enfield Cables, Thorn Electrical Industries, Belling, Glover and Main, MK Electric, Gestetner, JAP Industries, etc. Much industry has now gone, to be replaced by warehousing and retail parks.
The valley also became very important for London’s water supply, as the source of the water transported by the New River aqueduct, but also as the location for the Lee Valley Reservoir Chain, stretching from Enfield through Tottenham and Walthamstow.
A second significant corridor of canal, railways and industries was associated with the Brent, stretching from the Thames at Brentford, through Isleworth, Greenford, Alperton and Park Royal.
The Colne (the historic boundary between Middlesex and Buckinghamshire) forms much of the western boundary of the county of Greater London.
Significant tributaries include the Mole, Wandle, Ravensbourne (tidal reach known as ‘Deptford Creek’) with its tributary the Quaggy, and the Darent and its tributary the Cray which together form part of the eastern boundary of Greater London. Smaller, some mainly subterranean tributaries include the Hogsmill River, Beverley Brook, Neckinger and Effra.
The Wandle formed south London’s nearest equivalent to the Lea Valley, with an industrial corridor stretching from the Thames at Wandsworth through Merton and Mitcham to Beddington and Croydon. A smaller corridor followed the Ravensbourne from the Thames at Deptford Creek through Lewisham, and many of the smaller rivers also once had mills.
A number of canals or canalised rivers have been constructed in the London area, mostly in the late 18th and early 19th centuries. These were originally for goods traffic, which has largely ceased. Within London the canals carried coal from the docks to many canal-side gas works and power stations (for example Brimsdown), and timber to timber yards, furniture manufacturers etc. (for example in Edmonton). Although most of the canals still survive today, they are used primarily for leisure craft.
North of the Thames
Canal construction in the London area started with navigation works on the Lea and Stort from 1424 onwards, leading to the River Lee Navigation and Bow Back Rivers. Initially used for transport of agricultural product from Hertfordshire, this later became an important industrial waterway connecting the heavily industrialised Lea Valley with the docks. A short-cut to the Thames avoiding the winding mouth of the Lea (Bow Creek) and closer to central London was provided by the Limehouse Cut (1760).
A connection from London to the Midlands had been provided by the Oxford Canal since 1790, but this required navigation up the winding the upper Thames to Oxford. The completion of the Grand Junction Canal (later Grand Union) from the Thames at Brentford (1798 onwards) provided a more convenient route. In 1801 an arm was opened from the Grand Junction at Hayes to a large basin at Paddington. This was later linked to the Thames at Limehouse (close to the Limehouse Cut) by the Regent’s Canal, completed in 1820. This in turn was linked to the Lea system by the Hertford Union Canal or Hackney Cut (1830). The Regent’s Canal had many substantial basins (City Road Basin, Kingsland Basin, Battlebridge Basin, St Pancras Basin, Cumberland Basin etc.), originally lined with industries dependent on traffic from the docks.
The City Canal (1805) was built to provide a short-cut across the Isle of Dogs. This was later incorporated into the West India Docks and is no longer connected to the Thames at its upstream end. Other short canals connecting to the Thames included the Grosvenor Canal (1825) and the Kensington Canal (1828).
South of the Thames
The former Grand Surrey Canal (1807) was intended to run from the Thames at Rotherhithe to the industrial town of Mitcham, but got no further than Camberwell. It closed with the Surrey Commercial Docks in 1970 and has been filled. The Grand Surrey Canal linked to the Croydon Canal (1809) which continued as far as West Croydon; this closed in 1836.
Further afield a link from London to Bristol is provided by the Kennet & Avon Canal which connects the Avon at Bath via the River Kennet to the Thames at Reading. Basingstoke could once be reached via the Thames, Wey Navigation and the Basingstoke Canal. The south coast at Littlehampton could be reached via the Thames, Wey and the Wey and Arun Canal.
Courtesy : Wikipedia