The Almondsbury Interchange in

South Gloucestershire South Gloucestershire is a unitary authority area in the ceremonial county of Gloucestershire, South West England. Towns in the area include Yate, Chipping Sodbury, Kingswood, Thornbury, Filton, Patchway and Bradley Stoke. The southern p ...

, is one of 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 Northwestern Europe, off the coast of European mainland, the continental mainland. It comprises England, Scotlan ...

's largest motorway stack interchanges. The interchange is one of only three four-level stacks in the UK, and including slip roads covers . It is the interchange for the M5 at junction 15 and M4 at junction 20, and is situated at the northern fringes of

Bristol Bristol () is a City status in the United Kingdom, cathedral city, unitary authority area and ceremonial county in South West England, the most populous city in the region. Built around the River Avon, Bristol, River Avon, it is bordered by t ...

close to the village of

Almondsbury Almondsbury () is a large village and civil parish in South Gloucestershire, England. It is situated on the A38 road in the Avon Green Belt north of Bristol city centre. It is adjacent to junction 16 of the M5 motorway and Almondsbury Interc ...

, the Aztec West industrial estate, and

Bradley Stoke Bradley Stoke is a town and civil parish in South Gloucestershire, England, situated north-northeast of Bristol city centre.OS Explorer Map, Bristol and Bath, Keynsham & Marshfield. Scale: 1:25 000.Publisher: Ordnance Survey B4 edition (2013). ...

. When it opened in 1966, it was the most complex junction on the British motorway network, a free-flowing interchange on four levels. Since then traffic volumes have increased. At busy periods, the interchange becomes more difficult to negotiate safely. In an attempt to ease congestion, the Interchange has become part of a smart motorway. South Gloucestershire - Almondsbury Interchange

South Gloucestershire - Almondsbury Interchange

The interchange

The Almondsbury Interchange is immediately adjacent to junction 16 of the M5, which allows traffic on and off the motorway from the

A38 road The A38, parts of which are known as Devon Expressway, Bristol Road and Gloucester Road, Bristol, Gloucester Road, is a major A-class trunk road in England. The road runs from Bodmin in Cornwall to Mansfield in Nottinghamshire. It is long, mak ...

running between

and

Gloucester Gloucester ( ) is a cathedral city, non-metropolitan district and the county town of Gloucestershire in the South West England, South West of England. Gloucester lies on the River Severn, between the Cotswolds to the east and the Forest of Dean ...

. The slip roads from the A38 junction intertwine with those from the M5/M4 interchange. Unusually within the UK motorway system, this forces multiple lane changes for vehicles traversing some of the routes. The centres of the junctions are at Ordnance Survey Grid References ST 617837 (M5 J15/ Almondsbury Interchange) and ST 606833 (M5 J16/ A38), and are therefore apart. Almondsbury Interchange was the first four-level interchange in the United Kingdom. It was designed by Freeman Fox and Robert Earley. When it opened in 1966, it was the most complex junction on the British motorway network. The interchange was built by Richard Costain Ltd, with work commencing in May 1964. The bridge was opened by the

Queen Queen most commonly refers to: * Queen regnant, a female monarch of a kingdom * Queen consort, the wife of a reigning king * Queen (band), a British rock band Queen or QUEEN may also refer to: Monarchy * Queen dowager, the widow of a king * Q ...

on 8 September 1966.

Congestion

The interchange handles high volumes of traffic especially in the morning and evening rush hours. It is overlooked by the RAC Tower. Traffic travelling between the M5 and Second Severn Crossing can bypass the interchange by using the M49 motorway. Under normal conditions, traffic flows freely through the interchange. Congestion becomes a problem in heavy traffic flow, such as during the summer holiday season, because of the close proximity of the A38 junction. This makes the required changing of lanes when travelling west on the M5 much more problematic. The interchange is at the centre of a managed motorway project which covers junctions 19 to 20 on the M4 and 15 to 17 on the M5. This became fully operational in January 2014, after being installed over a two-year period. It involves the use of the hard shoulders on the M4 and M5 over seven miles of motorway during busy times, at which time a variable speed limit function is activated. Thirty-three new overhead gantries have been installed to advise motorists on the speed limits applicable at the time. The system is being enforced by speed cameras, and there are six emergency refuge areas for motorists who get into difficulties.

References

{{Motorways in the United Kingdom 1966 establishments in England Buildings and structures in South Gloucestershire District Motorway junctions in England Transport in South Gloucestershire District Transport infrastructure completed in 1966 M4 motorway M5 motorway