Plans to dig a tunnel to replace pylons and power lines from a beauty spot in Snowdonia have been given the go-ahead.

At a meeting of the Snowdonia National Park Authority’s Planning Committee yesterday, planning consent was granted for the erection of a tunnel head house to the south east of the Dwyryd estuary on the edge of the national park.

This development will enable the National Grid to proceed with plans to underground 3.4km of cabling that currently crosses the estuary overhead.

The undergrounding of the cables will enable the removal of 10 electricity pylons that have been a blot on the landscape since their erection in 1966 to transmit electricity from the Trawsfynydd nuclear power station.

The opening for the tunnel that will house the underground cables will be inside a tunnel head house located off the A496 to the north of the small settlement of Llandecwyn.

As the development spans two planning authorities, planning permission for a tunnel head house on the western side of the estuary will be determined by Gwynedd Council’s Planning Committee on 16 July.

The tunnel itself is not subject to planning permission as it is permitted under the Electricity Act 1947/57. All relevant environmental and archaeological organisations were consulted as part of the application, who were satisfied that the development would not have a detrimental impact on the landscape.

The work will begin in 2021 and is expected to take five years to complete, with a proportion of the work undertaken by local contractors.

Cllr Gareth Thomas said: “I’m happy to support this project, not only because of the clear economic benefit, but also because of its visual benefit. The Dwyryd estuary is one of the most beautiful places in Wales, but there is currently a glaring scar across the estuary and peninsula. The project will significantly improve the area’s appearance for the benefit of local people as well as visitors.”

On behalf of the National Park Authority, chair of the Planning Committee, Cllr Elwyn Edwards said: “While careful consideration must be given to an engineering scheme of this nature in a designated area, we are happy to support this scheme that will ultimately substantially improve the character of the landscape and the visual amenity of the Dwyryd estuary.”