Conwy Tunnel closure

[Hamma52]

Earlier today, a large vehicle fire engulfed the westbound carriageway of the A55 Conwy Tunnel. The road has been shut all day in both directions.

North Wales police deemed the fire under control later in the afternoon, yet stated that:

Due to the scale of the incident and the need for ongoing safety assessments, the Conwy Tunnel remains closed in both directions and is expected to remain closed for a significant amount of time. Detailed inspections will need to be carried out to determine the extent of any damage before the tunnel can be safely reopened

https://www.northwales.police.uk/news/north-wales/news/news/2025/june/conwy-tunnel-fire-latest-information/

At the moment, the A55 is shut at Llanfairfechan to J.19 at Llandudno Junction.
The diversion is huge, going down the A470 to Betws-y-Coed, then joining the A5 through the Ogwen Valley and Bethesda, before rejoining the A55 at J.11 for Bangor.

The A470 and A5 are busy roads at the best of times, especially around Llanrwst, Betws and Bethesda, so closure for a long period of time could be very disruptive indeed. The A55 up to the tunnel should reopen soon enough, yet the alternative route through Conwy is hardly suitable for large volumes of traffic.

Would the Conwy Tunnel reopen just eastbound? Could the eastbound carriageway be split in direction?

== Doublepost prevention - post automatically merged: 20 Jun 2025 ==

An update on this:

The A55 is now fully reopen, INCLUDING the Conwy Tunnel in both directions. However, the tunnel is down to 1 lane for both carriageways.

Incredible to get it reopen that quickly, however yesterday was definitely a warning shot as to what the region would look like without the tunnel.

The current structure is from the 90s, and with no fire mitigation systems other than ventilation fans and a tannoy alarm system. I know the Tyne Tunnel in Newcastle is fitted with sprinkler and mist systems. Whilst that wouldn't have helped yesterday, and with the increasing number of EVs on the UK's roads, would provide a different risk, having some sort of fire suppression system in the tunnel is surely overdue?

 

[Cloud Strife]

Would the Conwy Tunnel reopen just eastbound? Could the eastbound carriageway be split in direction?

The tunnel is set up for single carriageway operation, but it certainly should be improved with fire mitigation systems. Having said that, until the new tube of the Tyne Tunnel opened, it was also in an absolutely dreadful condition and not at all suitable for modern use.

I think here, the more sensible solution might be not only to improve the fire safety systems, but also to rebuild one of the tunnels so that a major fire in one tube doesn't affect the operation of the other one. They could easily create a new tunnel just to the south of the existing westbound tunnel, and the existing westbound tunnel could be kept as an emergency exit route.

 

[Hamma52]

A new tunnel would be incredibly expensive, but yesterday proved that the tunnel really is a ticking timebomb, and as you say, in desperate need of future proofing.

I fear that going off other Welsh road infrastructure projects, this won't happen, or will a ridiculously long time to happen (Head of the Valleys taking over 20 years?!) - either way, too late in the impending event of sustained tunnel closure.

Purely speculative at the moment, but with both improvement works at the Llanfairfechan roundabouts and the Third Menai Crossing both being shelved indefinitely, it would probably take a full closure for a sustained period of time before the tunnel was actually bought up to modern standards

 

[Bald Rick]

think here, the more sensible solution might be not only to improve the fire safety systems, but also to rebuild one of the tunnels so that a major fire in one tube doesn't affect the operation of the other one.

The tunnels were built through immersed tube, so both ’tunnels‘ are part of the same integral construction.

 

[stuu]

They could easily create a new tunnel just to the south of the existing westbound tunnel, and the existing westbound tunnel could be kept as an emergency exit route.

"Easily' is doing a lot of work in that sentence. Have you seen how much it costs to build roads across open fields in this country?