M4 (M48) River Severn crossing

The first crossing - the Severn Road Bridge
The concept of a crossing of the Severn Estuary had certainly existed since early in the 19th century. It was first solved by the railway companies, initially by a train/passenger ferry/train transfer at purpose-built jetties at both shores of the estuary, later by the building of the tunnel. Until the Severn Bridge was opened road transport to and from Wales via the A40 crossed the Severn at Gloucester and took the tortuous route via Ross-on Wye and Monmouth, or through the Forest of Dean and Chepstow. As a possible alternative light vehicles might take the inadequate and irregular ferry between Beachley and Aust.

M4 (M48) Severn Bridge - first crossingMott Hay and Anderson, with Freeman Fox and Partners, were the Engineers for the scheme, and it was built as a number of contracts. The first, the substructure, was started in March 1961, and completed by contractors John Howard and Co in March 1963. The superstructure contract was awarded to Associated Bridge Builders Ltd in March 1963 and completed in September 1966.

In parallel with this work, the Wye Bridge and Beachley Viaduct scheme was carried out by Cleveland Bridge and Engineering Co between July 1963 and September 1966. It is this cable-stayed bridge over the Wye which forms the boundary between England and Wales.

The adjoining road schemes were the section from Aust to Almondsbury (covered in the South West pages) and the Wye Bridge to Crick section. The latter contract, which started in March 1964, was let initially to Martin Cowley Ltd but completed by Fitzpatrick and Son (Contractors) Ltd. In the original plan, a roundabout at Crick was to mark the end of the motorway but a later decision by the Ministry of Transport permitted the 9.5 mile motorway extension from Crick to the Coldra, Newport (Junction 24). The roundabout was omitted and the motorway is carried over the A48 at Crick by a bridge

After the completion of the second Severn crossing, this section of the M4 was re-numbered the M48

The second Severn crossing
This is decribed in the South West Region section. Click here to view it.

Contract details




Cost (£million)

Severn bridge substructure Mott Hay and Anderson, Freeman Fox & Partners John Howard and Company


Severn Bridge Superstructure Mott Hay and Anderson, Freeman Fox & Partners Associated Bridge Builders Ltd


Wye Bridge and Beachley Viaduct Mott Hay and Anderson, Freeman Fox & Partners Cleveland Bridge and Engineering Co


M4 Aust to Almondsbury Mott Hay and Anderson, Freeman Fox & Partners Richard Costain (Civil Engineering) Ltd


M4 Wye Bridge to Crick Mott Hay and Anderson, Freeman Fox & Partners Martin Cowley Ltd  later taken over by Fitzpatrick and Son (Contractors) Ltd


Second Severn crossing W S Atkins, G Maunsell & Partners  


M49 and English approach roads   WS Atkins, G Maunsell & Partners  

Incl above