Wirral cable

An underground high voltage cable of approximately 33km is required through the Wirral peninsula.

Planning for cable installation

In planning, designing and installing the cables we aimed to minimise disturbance to communities and the environment. One of our initial ideas was to route the cables through the Dee Estuary as it is the most direct route, but this was not feasible. The movement of the sand on the bed of the river and the use of the estuary by shipping increased the possibility that the cables would not work properly or would be damaged. Also, the Dee Estuary is classed as an area of high environmental importance.

In February 2011 we published our preferred route corridor for the cable, which was quite wide at this stage, and we held a number of public information events to obtain feedback from the local community. Since this time, the feedback received from public consultation and statutory consultees, further investigations into the technical feasibility of construction and discussions with landowners have helped to develop a detailed cable route. Discussions with landowners and other interested parties resulted in minor revisions to this route.

Installing the cable

Prysmian Group is responsible for the Wirral Cable installation work, including all preparations and reinstatement.

Work planned in 2017

We will complete joining the cable sections together and when the weather improves, we’ll complete reinstatement of the land above the cables.

Reinstatement is a critical activity that must be completed in the right conditions. The process is very dependent on the weather and overall can take a few months from when we start in an area. Although we won’t necessarily be working on site all the time, when we are, there will be an increase in activity to and from our work area.

We may need to close a small number of roads and will post notices about any road closures in the News and Events section of our website.

Construction compounds

We established three temporary construction compounds during cable installation:- on the outskirts of Thornton Hough, near Arrowe Park and just off the A540 near Gordale.

We have now vacated the temporary compound near Thornton Hough and reinstated the land, and we're in the process of demobilising the Arrowe Park Compound. We anticipate using the A540 compound until our work is complete.

View documents relating to the Wirral cable

Work to the end of 2016

We finished laying the underground cables, joined the majority of cable sections together and reinstated the land in some areas.

Work to the end of 2015

During the year we laid a significant amount of underground cable across the Wirral peninsula, including along the A540. We also carried out work to join together the majority of the cable sections we’d laid – a process known as ‘jointing’.

During the year we successfully pulled cables through the pipes under the River Dee and laid cables along the banks of the river to connect into National Grid’s substation in Connah’s Quay.

Work to the end of 2014

Work to prepare for cable installation on land started in spring 2013 and continued throughout 2014. We established a temporary working corridor, around 20m wide, which has been fenced off while it is being used. Within this corridor we have installed two cables in a single trench approximately 1.2m deep and 750mm wide. The cables have been laid in sections of approximately 1km, with joints where the sections meet. The corridor has also been used to store material excavated from the trench dug for the cables and to install drainage and a temporary road for the delivery of the cables, which arrived on large drums.

In the autumn of 2014 we achieved two major milestones. We laid the first 36km of our cable, under the sea wall at Leasowe and out into Liverpool Bay. For more information on this work view the press release here or the fact sheet here and to see time lapse photography of the operation see here.

We also installed nine pipes under the River Dee, through which the cables that link our Flintshire Bridge converter station to National Grid’s substation in Connah’s Quay were successfully pulled in 2015 (see below).