National Grid is marking a major milestone on its Eryri Visual Impact Provision (VIP) scheme with the arrival of the Tunnel Boring Machine (TBM), which will be used to excavate the tunnel that will contain the new electricity cables that will replace the existing 3km of overhead line that cross the estuary.
The Visual Impact Provision project in Eryri National Park aims to reduce the visual impact of the overhead electricity line across the Dwyryd Estuary from Minffordd to Llandecwyn. National Grid has worked closely with stakeholders and the local community to implement the project, which includes constructing two new tunnel head houses, which will provide access to the tunnel, along with a sealing end compound to connect the underground cables with the remaining overhead line.
After being delivered to the site compound, the TBM will be unloaded and prepared to commence tunnelling in early 2025. Once assembled, the TBM will measure 166 metres long and weigh 436 tonnes. It's expected to complete tunnelling and reach its destination in Llandecwyn in mid-2026, with the pylons and overhead line due for removal in 2029.
National Grid and its contractor Hochtief UK have been working closely with the North and Mid Wales Trunk Road Agent (NMWTRA), Welsh Government, North Wales Police, relevant local authorities and a specialist haulage contractor, Fracht Group UK, to carefully plan the route and timings to minimise disruption to local people and traffic wherever possible.
Steve Ellison, National Grid’s senior project manager for Eryri VIP, said: "These deliveries have been many months in the planning and we work hard to minimise any disruption that deliveries of this kind can cause. The movements are occurring at these times to try and minimise disruption to the local road network and we appreciate the cooperation and understanding of the local community."
From Monday 18 November, for a period of up to three weeks, a total of 27 deliveries will be coming to the project site in Minffordd along the A55, A487 and A497.
The TBM is being transported from Germany, where it has been manufactured, via sea transport to Immingham Docks in North East Lincolnshire. It will then be transported to Chester services along the M56 before entering North Wales.
Of these deliveries, 21 will be Abnormal Indivisible Load (AIL) movements with eight loads requiring a full police escort and 13 loads requiring partial police escort. The other six deliveries will be normal HGVs which do not require any police escort.
There will be between one and four deliveries per day during the delivery period. The widest delivery loads will be travelling through North Wales on Monday 18 November 2024, Tuesday 19 November 2024 and Monday 25 November 2024. All deliveries are scheduled to take place on week days during daylight hours, and at times that aim to avoid congested areas during busy traffic periods.
The delivery loads will be moving at speeds of up to 40mph for the first section of the route via the A55 dual carriageway and then between 20mph and 30mph for the majority of the route via the A487. There will be times when the loads reduce in speed such as when passing through the narrowest part of the route at Penmorfa, where they will travel at walking speed.
On the days where the AIL movements are passing through the route, traffic management will be in place at the Minffordd roundabout in the form of 4-way temporary traffic lights.
In order to allow the large loads to safely turn right at the Minffordd roundabout, National Grid will be temporarily removing street signage from around the Minffordd roundabout, just as the load passes that area. To enable this to happen, the permanent street signage has been replaced with temporary, easily removable signage.
After the TBM has been successfully delivered to site, the permanent street signage and furniture will be fully reinstated.
More information about the Eryri VIP project can be found at www.nationalgrid.com/eryrivip.
ENDS
All electricity transmission owners are funded by a price control mechanism which is agreed with and set by Ofgem, the electricity and gas markets regulator. Ofgem has agreed a set of price controls and incentives for the period from April 2021 to March 2026, following the previous period (2013-2021). The new price controls and incentives include a provision of £465 million to mitigate the visual impact of existing electricity infrastructure in nationally protected landscapes in Great Britain.
For National Grid, which is the electricity transmission owner in England and Wales, this means considering the visual amenity of our existing infrastructure in National Landscapes and National Parks.
The Visual Impact Provision project has been advised throughout by an independent panel of senior landscape experts from leading environmental organisations including the National Trust, the Ramblers, the Landscape Institute and the Campaign for National Parks plus CPRW, Natural Resources Wales, Cadw, and their English counterparts. The Group is chaired by environmentalist and broadcaster, Chris Baines.
The Eryri VIP project is one of only five in England and Wales – alongside others in the Dorset National Landscape and Peak District National Park – that have been completed. There is also a project in the North Wessex Downs National Landscape that started work this year and a potential project in the Cotswolds National Landscape, which is in planning.