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Improvements to Anglesey power network to close A55 overnight


Essential work by SP Energy Networks to complete an upgrade to a main overhead power cable between Valley and Caergeiliog will see the A55, also known as the North Wales Expressway, closed for six hours overnight on Saturday January 12th from 9pm until 3am on Sunday the 13th.

The new 132kv wood pole overhead line is part of a £13m investment programme to reinforce the electrical infrastructure across Anglesey.

In order to safeguard road users and the project team, the work will necessitate a night time road closure for six hours on the North Wales Expressway - the A55. The details are:

  • Saturday January 12th from 9pm until 3am on Sunday the 13th January
  • Between junctions 3 and 4 of the A55

The reinforcement project will also improve the resilience of the local distribution network to the existing 38,000 homes and businesses across Anglesey, as well as facilitating further development and growth across for the future, which will include the decarbonisation of lifestyles and the continued introduction of electric vehicles.

While the vast majority of the work at Caergeiliog has been completed with minimal disruption to the public, the night time closure of the A55 is essential in order to complete the remaining works in a safe and timely manner.

SP Energy Networks has worked closely with Anglesey Highways Department to ensure the closure is timed when traffic levels will be much reduced.  The A55 is the main route towards Holyhead Port and as such, closure times have also been carefully agreed around ferry arrival/departure times to minimise any impact to drivers heading to and from there.

A diversion route will be in place during the night time closure and is approximately 1.7m (2.8km) long through Caergeiliog on the old A5.

Mark Sobczak, Head of 132kV Programmes at SP Energy Networks, said: "This is an important and innovative investment programme that improves network resilience for our 38,000 customers in and around Anglesey as well as facilitating future needs. As we move towards the increased uptake of electric vehicles, and the electrification of other sectors like heating, it will be vital that our villages, towns and cities have a robust and modern electricity network capable of supporting increased demands.

“We fully appreciate that the A55 is an essential route for the area and have worked closely with the Local Authority and its highways department to ensure this work is timed during one of the quietest periods following Christmas and avoiding key ferry times. We will endeavour to minimise disruption where possible but would advise anyone planning to travel within the night time closure to allow additional journey for the diversion.”

Media Information – Stephanie Todd: 0141 614 4535 (