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A55 road
The A55, also known as the North Wales Expressway (Welsh: Gwibffordd Gogledd Cymru), is a major road in Wales and England, connecting Cheshire and North Wales. The vast majority of its length from Chester to Holyhead is a dual carriageway primary route, with the exception of the Britannia Bridge over the Menai Strait and several short sections where there are gaps in between the two carriageways. All junctions are grade separated apart from a roundabout east of Penmaenmawr and another nearby in Llanfairfechan. Initially, the road ran from Chester to Bangor. In 2001, it was extended across Anglesey to the ferry port of Holyhead parallel to the A5. The road improvements have been part funded with European money, under the Trans-European Networks programme, as the route is designated part of Euroroute E22 (Holyhead – Leeds – Amsterdam – Hamburg – Malmö – Riga – Moscow – Perm – Ekaterinburg – Ishim).
The A55 begins at junction 12 of the M53, the southern end of the motorway, near Chester. It is known as the Chester southerly bypass between J39 Christleton and J36a Broughton. The A55 crosses the River Dee and the border into Wales, passing close to Broughton, Flintshire, and passing north of Buckley, Penyffordd and Northop. There is a major climb between Broughton and Dobshill (Junctions 36a Broughton to 35 Dobshill) though with no crawler lane. Junction 34/33b is point at which the A494 converges and then diverges with the A55. The road briefly has a three-lane section as westbound traffic from Queensferry can leave towards Mold. In the eastbound direction another short three-lane section allows vehicles to join the A494 or exit onto the A55 to Chester. Traffic taking the A55 into England must negotiate a tight 270 degree speed-limited single lane curve to climb up and over the A55/A494 at Ewloe loops. Plans to upgrade the A494 between this junction at Ewloe and Queensferry were rejected by the Welsh Government on 26 March 2008 due to their scale.
From Ewloe, the road is relatively flat until after Northop when it climbs up onto the flanks of Halkyn Mountain range, passing to the southwest of Holywell with major climbs between Northop and Halkyn (Junctions 33 and 32b) and Halkyn and Holywell Summit (Junctions 32 and 31). This section of road is notorious for poor weather conditions including fog, ice and snow in winter months. In fine weather, however there are extensive views over the River Dee estuary to the Wirral Peninsula, Liverpool and beyond. The highest part of the road is in the vicinity of Brynford at around 790 feet (240 m). The steep descent towards St Asaph is down the new Rhuallt Hill (Junctions 29 to 28), which also provides the first views of the mountains of Snowdonia in the far distance. There is a crawler lane on Rhuallt Hill for eastbound traffic. The road bypasses St Asaph to the north, and runs past Bodelwyddan and Abergele to reach the North Wales coast at Pensarn (Junction 23A). From here onwards to Bangor, the route is close to the North Wales Coast railway.
Two sections between (Junction 23) Llanddulas to (Junction 17) Conwy are assigned 70 mph (110 km/h) speed limits because they are actually special roads. This is because these sections were built under legislation for building motorways but they were never declared as motorways. Legally it means these two stretches of the A55 are neither part of the national UK motorway network nor trunk roads. As such, the national speed limit does not apply so 70 mph (110 km/h) signs (the maximum speed permitted on UK roads) are used instead. Unlike other sections of the A55 that have National Speed Limit (NSL) signage and are accessible to all motor vehicles, motorway restrictions are enforced on these two stretches of road (therefore no pedestrians, learner drivers, etc.)
A 50 mph (80 km/h) limit remains in force through the Colwyn Bay bypass (Old Colwyn to Mochdre). The restriction was imposed for several reasons. First as a safety precaution because the slip-roads on this stretch are unusually short due to the road's design. Part of it was built on a narrow swathe of land through the town that was once the North Wales coast railway; Colwyn Bay railway station had to be rebuilt and the track bed realigned to complete the underpass as the road used the former railway goods yard which was relocated to Llandudno Junction. The former four-track railway was reduced to two more northerly tracks to make space for the road. Secondly, the reduced speed limit was intended to reduce road noise for residents. However, since the completion of the Colwyn Bay bypass, the lower speed limit has been an unpopular decision with drivers.
The crossing of the estuary of the River Conwy is by means of an immersed tube tunnel, the first of its kind constructed in the United Kingdom. At 1060m, the tunnel is the longest road tunnel in Wales.
The decision to construct an immersed tube tunnel bypass followed an extensive public consultation, named the Collcon Feasibility Study. 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 430 metres (1,410 ft), following the old Roman road, was also worked up but rejected for cost and utility reasons as it would have required a very long crawler lane.
The tunnel was constructed by a Costain/Tarmac Construction joint venture, as pre-formed concrete sections, and then floated into position over a prepared trench in the bed of the estuary. 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.
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A55 road
The A55, also known as the North Wales Expressway (Welsh: Gwibffordd Gogledd Cymru), is a major road in Wales and England, connecting Cheshire and North Wales. The vast majority of its length from Chester to Holyhead is a dual carriageway primary route, with the exception of the Britannia Bridge over the Menai Strait and several short sections where there are gaps in between the two carriageways. All junctions are grade separated apart from a roundabout east of Penmaenmawr and another nearby in Llanfairfechan. Initially, the road ran from Chester to Bangor. In 2001, it was extended across Anglesey to the ferry port of Holyhead parallel to the A5. The road improvements have been part funded with European money, under the Trans-European Networks programme, as the route is designated part of Euroroute E22 (Holyhead – Leeds – Amsterdam – Hamburg – Malmö – Riga – Moscow – Perm – Ekaterinburg – Ishim).
The A55 begins at junction 12 of the M53, the southern end of the motorway, near Chester. It is known as the Chester southerly bypass between J39 Christleton and J36a Broughton. The A55 crosses the River Dee and the border into Wales, passing close to Broughton, Flintshire, and passing north of Buckley, Penyffordd and Northop. There is a major climb between Broughton and Dobshill (Junctions 36a Broughton to 35 Dobshill) though with no crawler lane. Junction 34/33b is point at which the A494 converges and then diverges with the A55. The road briefly has a three-lane section as westbound traffic from Queensferry can leave towards Mold. In the eastbound direction another short three-lane section allows vehicles to join the A494 or exit onto the A55 to Chester. Traffic taking the A55 into England must negotiate a tight 270 degree speed-limited single lane curve to climb up and over the A55/A494 at Ewloe loops. Plans to upgrade the A494 between this junction at Ewloe and Queensferry were rejected by the Welsh Government on 26 March 2008 due to their scale.
From Ewloe, the road is relatively flat until after Northop when it climbs up onto the flanks of Halkyn Mountain range, passing to the southwest of Holywell with major climbs between Northop and Halkyn (Junctions 33 and 32b) and Halkyn and Holywell Summit (Junctions 32 and 31). This section of road is notorious for poor weather conditions including fog, ice and snow in winter months. In fine weather, however there are extensive views over the River Dee estuary to the Wirral Peninsula, Liverpool and beyond. The highest part of the road is in the vicinity of Brynford at around 790 feet (240 m). The steep descent towards St Asaph is down the new Rhuallt Hill (Junctions 29 to 28), which also provides the first views of the mountains of Snowdonia in the far distance. There is a crawler lane on Rhuallt Hill for eastbound traffic. The road bypasses St Asaph to the north, and runs past Bodelwyddan and Abergele to reach the North Wales coast at Pensarn (Junction 23A). From here onwards to Bangor, the route is close to the North Wales Coast railway.
Two sections between (Junction 23) Llanddulas to (Junction 17) Conwy are assigned 70 mph (110 km/h) speed limits because they are actually special roads. This is because these sections were built under legislation for building motorways but they were never declared as motorways. Legally it means these two stretches of the A55 are neither part of the national UK motorway network nor trunk roads. As such, the national speed limit does not apply so 70 mph (110 km/h) signs (the maximum speed permitted on UK roads) are used instead. Unlike other sections of the A55 that have National Speed Limit (NSL) signage and are accessible to all motor vehicles, motorway restrictions are enforced on these two stretches of road (therefore no pedestrians, learner drivers, etc.)
A 50 mph (80 km/h) limit remains in force through the Colwyn Bay bypass (Old Colwyn to Mochdre). The restriction was imposed for several reasons. First as a safety precaution because the slip-roads on this stretch are unusually short due to the road's design. Part of it was built on a narrow swathe of land through the town that was once the North Wales coast railway; Colwyn Bay railway station had to be rebuilt and the track bed realigned to complete the underpass as the road used the former railway goods yard which was relocated to Llandudno Junction. The former four-track railway was reduced to two more northerly tracks to make space for the road. Secondly, the reduced speed limit was intended to reduce road noise for residents. However, since the completion of the Colwyn Bay bypass, the lower speed limit has been an unpopular decision with drivers.
The crossing of the estuary of the River Conwy is by means of an immersed tube tunnel, the first of its kind constructed in the United Kingdom. At 1060m, the tunnel is the longest road tunnel in Wales.
The decision to construct an immersed tube tunnel bypass followed an extensive public consultation, named the Collcon Feasibility Study. 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 430 metres (1,410 ft), following the old Roman road, was also worked up but rejected for cost and utility reasons as it would have required a very long crawler lane.
The tunnel was constructed by a Costain/Tarmac Construction joint venture, as pre-formed concrete sections, and then floated into position over a prepared trench in the bed of the estuary. 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.
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