National Grid is moving the electricity connection across the Dwyryd Estuary into a 3.4 km tunnel between Minffordd and Llandecwyn. Once the underground connection is operating, ten pylons and roughly 3 km of overhead line can be removed, opening up views across the estuary and the western edge of Eryri National Park.[1][2]
National Grid reported completion of the tunnelling drive on 13 October 2026. The next stage includes removing the boring machine, installing cables and continuing the headhouses and associated infrastructure at either end. The electricity undergrounding scheme remains under construction.
National Grid has completed the 3.4 km tunnelling drive beneath the Dwyryd Estuary between Minffordd and Llandecwyn. The tunnel will carry electricity cables allowing ten pylons and roughly 3 km of overhead line to be removed from Eryri’s landscape. Cable installation and associated construction remain ahead; National Grid targets pylon removal in 2029.