Powerline river crossings comprise both overhead lines and cable tunnels beneath rivers and estuaries. Overhead power lines are supported on towers (called pylons in the UK) which are usually significantly taller than overland pylons and are more widely spaced to cross the river in a single span. Tall pylons ensure that the electricity cables which they support provide an adequate safety clearance for river traffic.
Overhead crossings
The tallest and longest
overhead power line
An overhead power line is a structure used in electric power transmission and distribution to transmit electrical energy across large distances. It consists of one or more uninsulated electrical cables (commonly multiples of three for three-p ...
river crossings in the
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
are:
The tallest
electricity pylons in the UK are those of the
400 kV Thames Crossing, at
West Thurrock
West Thurrock is an area, former civil parish and traditional Church of England parish in Thurrock, Essex, England, located 17.5 miles (28.1 km) east south-east of Charing Cross, London. In 1931 the parish had a population of 5,153. On 1 Apr ...
, which are 190 m (630 ft) high. These were constructed by
BICC in 1965. The cables stretch 1300 m (4,500 ft) across the
River Thames
The River Thames ( ), known alternatively in parts as the The Isis, River Isis, is a river that flows through southern England including London. At , it is the longest river entirely in England and the Longest rivers of the United Kingdom, se ...
and have a minimum clearance of 76 m (250 ft). There are two 400 kV circuits that connect Littlebrook substation on the south bank to West Thurrock substation on the north side.
The longest powerline river crossing in the UK is the
Aust Severn Powerline Crossing
Aust Severn Powerline Crossing is the longest overhead power line span in the United Kingdom with a length of .
History
The crossing spans the River Severn between Aust and Beachley and is part of the National Grid.
It was commissioned in 19 ...
over the
River Severn
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, image = SevernFromCastleCB.JPG
, image_size = 288
, image_caption = The river seen from Shrewsbury Castle
, map = RiverSevernMap.jpg
, map_size = 288
, map_c ...
at
Aust
Aust is a small village in South Gloucestershire, England, about north of Bristol and about south west of Gloucester. It is located on the eastern side of the Severn estuary, close to the eastern end of the Severn Bridge which carries the M48 ...
, stretching 1700 m (5,310 ft) between towers 148 m (488 ft) high. The line was commissioned in 1959 and comprises two 275 kV electricity circuits forming part of the line between Iron Acton and Whitson substations. This pylon crossing is paralleled by the Severn-Wye Cable Tunnel beneath it, at almost the same location.
List of overhead powerlines
This is an incomplete list of overhead powerline river crossings in the UK.
Cable tunnel river crossings
In addition to overhead powerline river crossings, there are also underground powerline river crossings.
River Thames
Tunnels under the River Thames, from east to west are:
*
Thames Cable Tunnel
The Thames Cable Tunnel, also known as the Tilbury – Gravesend Cable Tunnel, is a tunnel carrying high-voltage electrical transmission lines beneath the lower River Thames between Tilbury and Gravesend. It remains the furthest tunnel downst ...
, between Tilbury and Gravesend, commissioned in 1970, comprising two 400 kV circuits between Tilbury and Kingsnorth substations
*
Dartford Cable Tunnel
The Dartford Cable Tunnel is a 2.4 km utility tunnel beneath the Thames, upstream of the Dartford Crossing. With a diameter of ~, it carries a 400 kV National Grid electrical transmission cable. It is accessible by foot as a crossing of ...
, between Littlebrook substation and West Thurrock substation, constructed 2003–04, comprising two 400 kV circuits
* Barking Cable Tunnel, between Barking and Thamesmead, comprising four 33 kV circuits
* Millennium Dome electricity cable tunnel, between West Ham substation and the Millennium Dome, comprising 11 kV circuits
*Deptford River Tunnel, between Deptford and Millwall Isle of Dogs, comprising 30 11 kV circuit
*
New Cross to Finsbury Market Cable Tunnel, between Bermondsey and Wapping, built between 2009 and 2017, comprises three 132 kV circuits
*Bankside river Tunnel, between Bankside and Blackfriars, connects Bankside substation and City Road substation, comprises 132 kV and 33 kV circuits
*Bankside – Charing Cross, crosses beneath Hungerford Bridge, comprises two 20 kV circuits
* Wimbledon – Pimlico Cable Tunnel, crosses the Thames between Nine Elms and Pimlico, comprises a 132 kV circuit
*
Battersea Power Station
Battersea Power Station is a decommissioned Grade II* listed coal-fired power station, located on the south bank of the River Thames, in Nine Elms, Battersea, in the London Borough of Wandsworth. It was built by the London Power Company (LPC) ...
Tunnels
*
London Power Tunnels Kensal Green to Wimbledon, crosses the Thames between Wandsworth and Hurlingham, constructed between 2011 and 2016, comprises a single 400 kV circuit.
Cable tunnels under other rivers
Other underground tunnel cable crossings are:
*
River Medway Cable Tunnels under the lower River Medway between Grain and Chetney Marshes, Kent, built between 1973–76, comprises two 400 kV circuits
*
Fawley Tunnel under Southampton Water between Fawley and Chilling, built between 1962 and 1965, comprises two 400 kV circuits
*
Severn-Wye Cable Tunnel under the River Severn and Wye between Aust and Newhouse, two 400 kV circuits.
This runs parallel to the Severn overhead pylon crossing (see above), and was commissioned in 1972.
References
*
{{DEFAULTSORT:Powerline River Crossings In The United Kingdom
United Kingdom
The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and North ...
Energy in the United Kingdom
Electric power infrastructure in the United Kingdom
Electric power transmission in the United Kingdom