April / May 2021 – Having completed the Northern section of the underpass work is close to completion on the Southern section. The photo below shows construction of this southern section into the embankment we have constructed.
The below photo shows the concrete being poured on the platform that will be the foundation for the westbound carriageway when completed, enabling us to switch the carriageway onto the section leaving an area in the centre so barrier installation works can be completed.
Looking in cross section we can see the current position from the diagram below.
Working nights on the 9th, 10th and 11th May the Westbound Carriageway will be closed to remove existing Traffic Management.
Working nights on 12th, 13th and 14th May the Eastbound Carriageway will be closed to remove existing Traffic Management.
Diversions will be in place for the respective lane closures between J15 and J16 via the A419.
The below diagram shows how the east and westbound lanes will sit on the new structure whilst earth is removed from the underpass whilst allowing motorway traffic to be unhindered.
Once barrier work is completed excavation of the underpass will continue and construction of the Southern Access Road will continue through it.
Motorway traffic will return to its usual configuration with hard shoulders restored as below.
06th July 2020 – Griffiths have commissioned Wessex Archaeology to undertake the archaeological mitigation during the construction of the Wichelstowe Southern Access Road. Site work is well underway and late prehistoric, Roman and medieval sites all showing up along the route of the road. Please click this LINK to see details of progress on the Wessex Archaeology website for this work.’
15th June 2020 – This Thursday – 18th June – we plan to switch M4 westbound traffic onto a temporary embankment. This will allow us to construct the north half of the M4 underpass for Wichelstowe Southern Access Road. We plan to switch the east-bound on the 6th July.