Start date: 28/10/2026 | End date: 24/02/2027
Replacement of lighting and associated infrastructure within the A40 Gibraltar Tunnel in Monmouth, will commence on 28/10/2026 for 17 weeks.
The works will be carried out over 17 weeks under Contraflow arrangements – Excluding 2 weeks over Xmas / New Year.
Full closures will be required on specific dates for both the A40 Southbound carriageway and the A40 Northbound carriageway at Gibraltar Tunnel, to enable Contraflow arrangements and for the Contraflow to be installed and removed.
Proposed programme of traffic management restrictions:
Details of Restrictions (Dates may be subject to change but are currently planned for: | Start Date and Time** | End Date and Time** | Notes |
Overnight closures of Southbound and Northbound carriageways at Gibraltar Tunnel – To install Southbound Contraflow
| Wed. 28/10/26
| Thurs 29/10/26
| 1 Night |
Full closure of Southbound carriageway at Gibraltar - During Southbound Contraflow
| Wed. 28/10/26
| Fri. 18/12/26
| 7 weeks |
Overnight closures of Southbound and Northbound carriageway at Gibraltar Tunnel – To remove Southbound Contraflow
| Thurs. 17/12/26
| Fri. 18/12/26
| 1 Night |
Overnight closures of Southbound and Northbound carriageway at Gibraltar Tunnel – To install Northbound Contraflow
| Mon. 04/01/27
| Tue. 05/01/27 | 1 Night |
Full closure of Northbound carriageway at Gibraltar - During Northbound Contraflow
| Mon. 04/01/27
| Wed. 24/02/27
| 8 weeks |
Overnight closures of Southbound and Northbound carriageway at Gibraltar Tunnel – To remove Northbound Contraflow
| Tues. 23/02/27
| Wed. 24/02/27 | 1 Night |
** dates provisional, may be subject to change
Diversions will be in place and signed when the following are in place:
A40 Southbound and Northbound carriageway at Gibraltar Tunnel - For the Southbound Contraflow to be installed and removed
A40 Southbound and Northbound carriageway at Gibraltar Tunnel - For the Northbound Contraflow to be installed and removed
Traffic along the diversion route will be monitored to identify any issues / additional mitigation measures that may need to be considered.
For further information, please contact Traffic Wales on 0300 123 1213 or via Twitter @TrafficWalesS