Four lanes of traffic will remain open during the daytime. Temporary traffic management will take place in early Construction is due to complete by spring Skip to main content. About cookies. We are addressing network issues on this section of the A Part of:. Why we are doing it. The scheme. We are improving safety along a 2. We are replacing these areas with: combined access road active travel route between junction 12 and 13 We are improving the road's drainage system to reduce the risk of flooding in the area.
His eventful life included a near-death experience when a fellow sailor accidentally discharged a revolver. Now you can discover Tom's story by Conwy Tunnel, A55 Expressway. Six sections of concrete tunnel tube were cast in a basin excavated near Morfa Conwy.
Each section weighed c. The cross-section was large enough for two lanes of traffic to run easily and safely through the tubes. This ruled out another bridge by the castle on aesthetic grounds, since it would have damaged the view of the world heritage site Conwy Castle, and the two bridges by Robert Stephenson and Thomas Telford.
Another alternative bridge crossing was proposed at Deganwy, but this too was ruled out for aesthetic reasons. An inland alternative with heavy grades which would have passed over Bwlch y Ddeufaen pass at metres 1, ft , following the old Roman road, was also worked up but rejected for cost and utility reasons. The 3 million tonnes of silt and mud extracted to create the trench in which the tunnel sections sat, were vacuumed to one side of the construction site, as to let them drift down river would have harmed the large mussel fishing beds downstream.
The silt was deposited upstream of the bridge at Conwy which created a large new area of low-lying land which was subsequently given to the RSPB for a wildlife preserve.
The casting basin for the tunnel sections was later converted into a new marina in the lower estuary. Because of the valuable fishery in the river and also because of the history of heavy metal mining in the catchment of the river, extensive ecological assessments were made both prior to the construction of the tunnel and subsequently. These studies finally concluded that no significant environmental damage had been caused. The Penmaenbach Tunnels are in the distance.
Leaving Conwy in a westerly direction, the construction of this section has involved major civil engineering works because it crosses two major headlands: Penmaenbach Point and Penmaenan Point.
Work has involved the cutting of several hard rock tunnels beneath the sea cliffs. The first to be built in was the Penmaenbach Tunnel which carried motor traffic to Penmaenmawr.
Two smaller tunnels through Penmaenan Point, opened , carried the road onto Llanfairfechan. This new route, carrying traffic in both directions, relieved the original coach road built by Telford in the early 19th century. Cut into the cliffs by hand, this narrow, winding route hugged the contours around both steep headlands.
Telford's route has now been converted into a cycleway across Penmaenbach and Penmaenan Points. Originally at the western end Llanfairfechan of the modern Pen-y-Clip tunnel, access was only allowed in an easterly direction because travelling the other way would mean heading the wrong way up the eastbound carriageway. However, in a purpose-built bridge - over the westbound carriageway - was constructed to allow unrestricted access to cyclists and walkers.
The s alignment was used until a new two-lane Penmaenbach Tunnel opened in to carry westbound traffic. Eastbound traffic would now travel through the Penmaenbach Tunnel using both its original lanes. Four years later, work to build the Pen-y-clip tunnel was completed. Like at Penmaenbach it carried westbound traffic while the original road carried vehicles in the opposite direction. Both new routes were subject to an advisory 50 mph speed limit until these were lifted in as there had been few accidents.
However traffic travelling eastbound on the s cliffhugging route still faced speed restrictions at both tunnel locations. Plans to rectify the awkward alignment by building another tunnel parallel to the current westbound tunnel as originally intended when the westbound tunnel was proposed have been discussed for several years.
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