For eagle-eyed readers of this blog, you may be asking where is Part Six, Newport’s railway bridge? It shall be featured at a later date, when Network Rail have finished repairs on the bridge and the current scaffolding is removed.

The M4 motorway’s Usk Bridge and Brynglas Tunnels were originally planned by Newport Corporation in August 1959 in a plan submitted to the Ministry of Transport.

Work started on the £3m project, led by engineer Sir Owen Williams, on 10 September 1962. Both structures were complete and open to traffic on 5 May 1967; thus becoming one of the first sections of the M4 in Wales. During the construction several houses on Brynglas Road had to be demolished due to structural weaknesses caused by the tunnelling.

Almost as soon as the M4 Newport bypass (junctions 24 to 28) had opened, the traffic levels grew to such a degree that the road had to be widened to three lanes in each direction. This was finished in 1982 with the exception of the tunnels and Usk Bridge, which remains dual two-lane sections (junctions 25-26).

The Usk Bridge and tunnels remain a bottleneck on the motorway.

A new M4 relief road south of Newport was proposed, but on 15 July 2009 the National Assembly for Wales dropped the scheme. Hence the A48 Southern Distributor Road, a two-lane dual carriageway connecting M4 junction 24 to junction 28, remains the alternative route.

However, the plans were revived in 2011 with indications of support from the Treasury given in April 2013. There was controversial media speculation that it would be the United Kingdom’s second full toll-paying motorway. In July 2014, the Welsh Transport Minister, Edwina Hart, stated that the scheme, following the so-called ‘black route’, would go ahead and could be completed by 2022.