Ground investigations begin at the Dwyryd Estuary, Snowdonia

Surveys to be conducted to help plan works to remove a section of overhead line across the estuary.

16 Oct 2017


  • Ground investigations at the Dwyryd Estuary until the end of October
  • Works will help National Grid develop plans which could see section of overhead power line removed
  • Existing connection from Garth to Cilfor could be placed in a tunnel


A short programme of ground investigation survey work has begun in and around the Dwyryd Estuary.  These works will help develop plans which could see a section of overhead line that runs across the estuary, from Garth to Cilfor, removed and the electricity connection placed in a tunnel.

The work, which will run until the end of October 2017, is part of National Grid’s Visual Impact Provision (VIP) project.  This is a major national initiative to reduce the visual impact of existing high voltage power lines in protected areas across Wales and England. 

National Grid has been working with local organisations including the Snowdonia National Park Authority, Gwynedd Council, Gwynedd Archaeological Trust, Cadw, the National Trust and Natural Resources Wales to find the best way to enhance the landscape and replace the overhead line with an underground solution.

The results of the survey work will help National Grid to understand the geology of the area in and around the estuary and develop detailed engineering designs.

The works will be carried out at a number of locations across the Dwyryd Estuary and surrounding areas, some of which will be accessed by hovercraft.  A mixture of boreholes and pits will be dug using a machine excavator and drilling rigs.  Temporary fencing will be placed around the sites to protect pedestrians and animals.

Experts including ecologists, archaeologists and safety specialists will be on hand to make sure that any disruption to residents and users of the estuary is kept to a minimum.  A site office has been set up in Penrhyndeudraeth, opposite the railway station.

Before National Grid finalises plans, a public consultation will be carried out to seek the views of the local community.

Hector Pearson, National Grid VIP Project Manager, said: “This work is an important stage in the development of our plans to reduce the visibility of existing electricity infrastructure in such a nationally important landscape.  

“We are committed to enhancing the natural beauty, culture and environmental heritage found in the Snowdonia National Park, and will continue to work closely in partnership with stakeholders to mitigate the visual impact of our transmission lines.”

To find out more about the work taking place in the Snowdonia National Park or for more information about the VIP project, please contact the project team on FREEPHONE 0800 019 1898, email visualimpact@nationalgrid.comor visit the website

Contact for media information only

Press officer - Infrastructure Projects
Jeanette Unsworth
+44 (0)7785 290230

Share this page

Notes for editors

Notes to Editors:

National Grid is one of the largest investor-owned energy companies in the world and was named Responsible Business of the Year 2014 by Business in the Community. This accolade acknowledges all of our efforts in getting involve with the things that really matter to us and to society. We own and manage the grids that connect people to the energy they need, from whatever the source.  In Britain and the north-eastern states of the US we run systems that deliver gas and electricity to millions of people, businesses and communities.

In Britain, we run the gas and electricity systems that our society is built on, delivering gas and electricity across the country.  In the North Eastern US, we connect more than seven million gas and electric customers to vital energy sources, essential for our modern lifestyles.

National Grid in the UK:

  • We own the high-voltage electricity transmission network in England and Wales, operating it across Great Britain
  • We own and operate the high pressure gas transmission system in Britain
  • We also own a number of related businesses including LNG importation, land remediation and metering
  • Our portfolio of other businesses is mainly concerned with infrastructure provision and related services where we can exploit our core skills and assets to create value. These businesses operate in areas such as Metering, Grain LNG Import, Interconnectors and Property. National Grid Carbon Ltd is a wholly owned subsidiary of National Grid. It undertakes Carbon Capture Storage related activities on behalf of National Grid.

Find out more about the energy challenge and how National Grid is helping find solutions to some of the challenges we face at

National Grid undertakes no obligation to update any of the information contained in this release, which speaks only as at the date of this release, unless required by law or regulation.

Related Videos

Where Energy Comes From

Where Energy Comes From

Tags:gas, National Grid UK, electricity, uk, Corporate Videos, energy

National Grid offers T-pylon for the first time in the UK.

National Grid offers T-pylon for the first time in the UK.

Tags:National Grid UK, youtube, managing the energy networks, uk, Corporate Videos, electricity

The Future of Energy

The Future of Energy

Tags:gas, energy, Corporate Videos, electricity