The Thelwall Viaduct () is a

steel Steel is an alloy made up of iron with added carbon to improve its strength and fracture resistance compared to other forms of iron. Many other elements may be present or added. Stainless steels that are corrosion- and oxidation-resistant ty ...

composite

girder A girder () is a support beam used in construction. It is the main horizontal support of a structure which supports smaller beams. Girders often have an I-beam cross section composed of two load-bearing ''flanges'' separated by a stabilizing ' ...

viaduct A viaduct is a specific type of bridge that consists of a series of arches, piers or columns supporting a long elevated railway or road. Typically a viaduct connects two points of roughly equal elevation, allowing direct overpass across a wide v ...

Lymm Lymm is a village and civil parish in the Borough of Warrington, Cheshire, England, which incorporates the hamlets of Booths Hill, Broomedge, Church Green, Deansgreen, Heatley, Heatley Heath, Little Heatley, Oughtrington, Reddish, Rushgreen and ...

Warrington Warrington () is a town and unparished area in the borough of the same name in the ceremonial county of Cheshire, England, on the banks of the River Mersey. It is east of Liverpool, and west of Manchester. The population in 2019 was estimat ...

England England is a country that is part of the United Kingdom. It shares land borders with Wales to its west and Scotland to its north. The Irish Sea lies northwest and the Celtic Sea to the southwest. It is separated from continental Europe b ...

. It carries the

M6 motorway The M6 motorway is the longest motorway in the United Kingdom. It is located entirely within England, running for just over from the Midlands to the border with Scotland. It begins at Junction 19 of the M1 and the western end of the A14 at t ...

across the

Manchester Ship Canal The Manchester Ship Canal is a inland waterway in the North West of England linking Manchester to the Irish Sea. Starting at the Mersey Estuary at Eastham, near Ellesmere Port, Cheshire, it generally follows the original routes of the river ...

and the

River Mersey The River Mersey () is in North West England. Its name derives from Old English and means "boundary river", possibly referring to its having been a border between the ancient kingdoms of Mercia and Northumbria. For centuries it has formed part ...

. It is between

junction Junction may refer to: Arts and entertainment * ''Junction'' (film), a 2012 American film * Jjunction, a 2002 Indian film * Junction (album), a 1976 album by Andrew Cyrille * Junction (EP), by Basement Jaxx, 2002 * Junction (manga), or ''Hot ...

s 20 and 21 of the M6, the former being also known as junction 9 of the M56.

Structure

It comprises two separate bridges, one of long carrying the northbound carriageway, the longest motorway bridge in England when it was opened in July 1963, and one long carrying the southbound carriageway, opened in 1995. The longest single span is that of crossing the Ship Canal.

History

The scheme was announced on Thursday 9 July 1959 by Minister of Transport

Harold Watkinson Harold Arthur Watkinson, 1st Viscount Watkinson, (25 January 1910, in Walton on Thames – 19 December 1995, in Bosham) was a British businessman and Conservative Party politician. He was Minister of Transport and Civil Aviation between 1 ...

, with the Gathurst Viaduct and Creswell Viaduct, near Stafford, over the

River Sow The River Sow is a tributary of the River Trent in Staffordshire, England, and is the river that flows through Stafford. Course The river rises to the south of Loggerheads, near Broughton and flows south-east beside the villages of Fairoak ...

. The bridge would cost £5,056,678, and was to be built by

Leonard Fairclough & Son Leonard Fairclough & Son Ltd was a construction firm based in Adlington, Lancashire, England. History The firm was founded by Leonard Fairclough, a stonemason in Adlington who established his business in 1883. Leonard's son, Leonard Miller Fa ...

, and designed by Sir James Drake.

Construction

Work started in September 1959, and was to be finished by March 1962. 10,500 tons of steel superstructure was made by

Dorman Long Dorman Long & Co was a UK steel producer, later diversifying into bridge building. It was once listed on the London Stock Exchange. History The company was founded by Arthur Dorman and Albert de Lande Long when they acquired ''West Marsh ...

. Concrete was supplied by Four Square Industries of

Middlewich Middlewich is a town in the unitary authority of Cheshire East and the ceremonial county of Cheshire, England, east of Chester, east of Winsford, southeast of Northwich and northwest of Sandbach. The population at the 2011 Census was 13,595 ...

. On Thursday 16 May 1963, the last two girders were put into place. The bridge had taken longer to build than expected, and the motorway was due to open on Monday 29 July 1963. The bridge was designed to take up to 79,000 vehicles per day. In August 1990 it was proposed to build a second viaduct, to start in 1992. The £52.5m contract was awarded to Tarmac Construction of Wolverhampton in October 1992, with consulting engineers

Pell Frischmann Pell Frischmann (PF) is a multi-disciplinary engineering consultancy based in London that provides structural and civil engineering, planning, design, and consulting services. Pell Frischmann employs over 1000 staff worldwide with 8 offices acros ...

. Junctions 20 and 21a would be remodelled. Concrete came from Pochin Group of Middlewich.

Maintenance

In July 2002 a failed

roller bearing In mechanical engineering, a rolling-element bearing, also known as a rolling bearing, is a bearing which carries a load by placing rolling elements (such as balls or rollers) between two concentric, grooved rings called races. The relative m ...

was discovered and it became necessary to close all but one northbound lane. As the M6 at the time carried an estimated 150,000–160,000 vehicles per day, this led to serious congestion. The viaduct was not completely reopened to daytime traffic until February 2005, and subsequently remained partially closed at night for further remedial work to take place. In all, 148 bearings were replaced, the repair scheme costing around £52 million. The bridge's height and openness to the elements mean that it has frequently been the subject of speed reductions because of strong gusts of wind that badly affect the stability of high-sided vehicles. On several occasions lane closures have resulted as a consequence of articulated vehicles simply being blown over. However, the open sides of the bridge are a deliberate design feature to reduce the likelihood of snow drifts building on the carriageways.

Events

In April 2011 a massive

free party A free party is a party "free" from the restrictions of the legal club scene, similar to the free festival movement. It typically involves a sound system playing electronic dance music from late at night until the time when the organisers d ...

took place under the bridge, with reportedly over 5,000 ravers in attendance.

1971 accident

At approximately 8am on 13 September 1971 thick fog led to a catastrophic multiple vehicle crash on the viaduct. More than 200 cars, trucks and tankers piled up, five vehicles burst into flames, 10 people were killed and 70 injured. It was the worst accident ever recorded on British roads at that time.

External links

The Motorway Archive website

References

{{Reflist Bridges across the River Mersey Bridges in Cheshire Bridges completed in 1963 Bridges completed in 1995 Motorway bridges in England Viaducts in England M6 motorway