Tideway

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The lower course of the Thames in 1840
The lower course of the Thames in 1840
Teddington Weir marks the start of the Tideway
Teddington Weir marks the start of the Tideway

The Tideway is a name given to the part of the River Thames in England that is subject to tides. This stretch of water is downstream from the Teddington Lock and is just under 160 km long. The Tideway includes the Thames Estuary, Thames Gateway and the Pool of London.

Contents

[edit] Tidal activity

Depending on the time of year, the river tide rises and falls twice a day by anything up to 7 m (24 ft) and takes longer to flow out (between 6 to 9 hours) than it does to flow in (4 to 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 than London Bridge, and Teddington about an hour later. 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 to deal with this threat,


[edit] Responsibilities

A Fast Response Targa 31 boat of the Marine Support Unit of the Metropolitan Police
A Fast Response Targa 31 boat of the Marine Support Unit of the Metropolitan Police

This part of the river is managed by the Port of London Authority and is often referred to as the Port of London. The upstream limit of the PLA's authority is marked by an obelisk just short of Teddington Lock. The PLA is responsible for just one lock on the Thames - Richmond Lock.

Within London the Thames is policed by the Thames Division, the River Police arm of London’s Metropolitan Police. Essex Police and Kent Police have responsibilities on the parts of the river downstream outside the metropolitan area. Notable criminal investigations have included the Roberto Calvi and Torso in the Thames cases. The London Fire Brigade has a fire boat on the river.

RNLI E class lifeboat based at Chiswick Pier performing a rescue
RNLI E class lifeboat based at Chiswick Pier performing a rescue

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 the tidal River Thames. As a result, there are four lifeboat stations on the river Thames based at Teddington, Chiswick Pier, Tower Pier and Gravesend. [1]

[edit] Navigation

River traffic around Waterloo Pier in 2008
River traffic around Waterloo Pier in 2008
The Thames Lock on the Grand Union Canal at Brentford
The Thames Lock on the Grand Union Canal at Brentford

The river is navigable to large ocean-going ships as far as the Pool of London and London Bridge. Today little commercial traffic passes above the docks at Tilbury and central London sees only the occasional visiting cruise ship or warship, moored alongside HMS Belfast and a few smaller aggregate or refuse vessels, operating from wharves in the west of London. The tidal part of the river has a speed limit of 8 knots (15 km/h) west (upstream) of the Wandsworth Bridge;[2] east of this point, there is no speed limit although boats are not allowed to create undue wash. An episode of Top Gear in 2007 showed Jeremy Clarkson driving a boat at claimed speeds of up to 70 miles per hour (113 km/h) near Canary Wharf.

The tidal river is used for leisure navigation. In London sections there are many sightseeing tours in tourist boats, past the more famous 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 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 Ham to Greenwich. Thames meander challenges along the length of 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.

[edit] Environment

The River Thames flooding at Chiswick Lane South in London's W4 postal district.
The River Thames flooding at Chiswick Lane South in London's W4 postal district.

Some low-lying areas beside the tidal section of the Thames regularly flood at spring tides. However, in recent years, the flooding has been occurring more frequently at unusual times. One such example exists at Chiswick Lane South in London's W4 postal district, where the river now bursts its banks almost daily between March and September.[citation needed]

Although efforts to clean up the Tideway have led to the reintroduction of marine life and birds, the environment of the Tideway is still poor. High levels of rainfall in London cause hundreds of thousands of tonnes of raw sewage to be poured into the Tideway several times per year, causing the deaths of marine life and health hazards for river users.

[edit] Sections of the Tideway

[edit] Thames Estuary

Main article: Thames Estuary

The Thames Estuary applies to 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 the Greater Thames Estuary and is one of the largest inlets on the coast of Great Britain. It has the world's second largest tidal movement, where the water can rise by 4 metres moving at a speed of 8 miles per hour. The whole estuary extends up the river into London near Tower Bridge, but this is divided into the Outer Estuary up to the Isle of Sheppey, and the Inner Estuary, designated the Thames Gateway above the Isle of Sheppey. The shore of the Outer estuary consists of saltmarshes and mudflats, but there are man-made embankments along much of the route where the land behind is now cultivated or used for grazing. Parts of the Outer estuary constitute a major shipping route.

[edit] Thames Gateway

Main article: Thames Gateway
The Grain Tower, Isle of Grain 1855, and causeway seen at low tide 2008.
The Grain Tower, Isle of Grain 1855, and causeway seen at low tide 2008.
The Queen Elizabeth II Bridge
The Queen Elizabeth II Bridge

The Gateway is some 40 miles (60 KM) long, stretching from the Isle of Sheppey to Westferry in Tower Hamlets. Its boundary was drawn to capture the riverside strip that formerly hosted many land extensive industries, serving London and 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.

Tributaries

Islands

Major Crossings

[edit] Pool of London

Main article: Pool of London
Bridge open to admitHMS Northumberland (F238)
Bridge open to admit
HMS Northumberland (F238)

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 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 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, ofen using converted warehouses. In the Upper Pool this provided scope for office development in the City of London and Southwark.

Major Crossings

[edit] Inner London

London Bridge with the Gherkin in the background
London Bridge with the Gherkin in the background
Blackfriars Bridge with St Paul's Cathedral behind
Blackfriars Bridge with St Paul's Cathedral behind
Lambeth Palace, photographed looking east across the River Thames.
Lambeth Palace, photographed looking east across the River Thames.
Battersea Power Station viewed from the north bank of the River Thames at Pimlico.
Battersea Power Station viewed from the north bank of the River Thames at Pimlico.

Between London Bridge and Putney Bridge, the river passes through Central London and some of the most famous landmarks.

North Bank South Bank
Monument
St Paul's Cathedral
Inner Temple
Somerset House
Victoria Embankment
HMS President
HMS Wellington
Cleopatra's Needle
Charing Cross railway station
Norman Shaw Building
Houses of Parliament
Tate Britain
Thames Embankment		 Southwark Cathedral
St Saviour's Dock
Globe Theatre
Tate Modern
Royal National Theatre
Royal Festival Hall
London Eye
Albert Embankment
County Hall, London
St Thomas' Hospital
Lambeth Palace
SIS Building
Battersea Power Station

Riverboats carry tourists up down and across the river, and also provide regular commuter service.

Major Crossings

Tributaries

[edit] Outer London

Putney Bridge
Putney Bridge
Historic riverside pub, Strand-on-the-Green, Chiswick
Historic riverside pub, Strand-on-the-Green, Chiswick
View from Richmond Hill, Richmond.
View from Richmond Hill, Richmond.

From Putney Bridge to Teddington Lock, the river passes through inner and outer suburbs like Hammersmith, Chiswick, Barnes, Richmond on Thames and Ham. This part of 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, stretchs from Putney to Mortlake.

Tributaries

Islands

Major Crossings

[edit] See also

[edit] References

  1. ^ http://news.bbc.co.uk/1/hi/england/1739401.stm BBC News Wednesday, 2 January, 2002, ‘’Thames lifeboat service launched’’.
  2. ^ Port of London Notice to Mariners No. 14 of 2006, River Thames Speed Limits

[edit] External links