97 up: Caithness overhead line team completes tower construction and wiring works

A team working in Caithness has achieved two major milestones on the way to upgrading the spine of the county’s onshore electricity transmission network between Dounreay and Mybster.  All main steel transmission towers associated with the project are now complete.  At the weekend, helped by the calm weather conditions, the final major sections of wiring works were also finished.

Balfour Beatty has been working on behalf of Scottish and Southern Electricity Networks (SSEN) since November 2014 to build a replacement 275 kilovolt overhead line which will connect substations at Dounreay, Thurso South (near Geiselittle) and Spittal. An additional 132 kilovolt line has also been built to strengthen the existing network south of Spittal to Mybster.

All of the new transmission towers in Caithness are now complete, apart from final connection towers at Spittal substation and two temporary towers between Dounreay and Thurso South. Once the 3 short linking spans of wiring at these locations are in place, they will allow the new lines to be energised in stages, starting in April 2017 as planned. The site team has achieved this in 700 days of working without any safety incidents or reportable injuries to members of the team.

Michael Cowie, Construction Manager for SSEN, said:

“Completing the last tower is a significant milestone for everyone involved in what is a very challenging project. A lot of effort has gone into reaching this stage before the worst of this winter’s weather. The wiring of the towers is also finished ahead of schedule and the whole team is focused on preparations for the work that will follow next year.

“The progress we have made is particularly pleasing because of the project’s excellent safety performance. The commitment of Balfour Beatty’s staff and construction teams has been fantastic, working all year round, sometimes in difficult conditions. Keeping everyone on site safe has relied on the alertness of the whole team and determination to stop work and take action whenever a potentially hazardous situation was identified.

“This couldn’t be done without a huge team effort and I would like to thank everyone involved – from Balfour Beatty staff and subcontractors on site, to support staff, landowners, local communities, the Highland Council and all the other public bodies who contribute to our work.”

Balfour Beatty’s Senior Project Manager Bruce Tumenta added:

“The important milestones that have been achieved are the result of good leadership, real teamwork and strong relationships throughout our own and SSEN’s project teams.

“For over 700 days, hundreds of different people have been working towards the delivery of the project both on and off site. As a result of all that work and the care that has been taken, there have been no safety incidents and – most importantly – no-one has been hurt. That is something worth recognising and celebrating, even while we keep focused on what remains to be done. I would like to thank everyone who has played their part.”

To date, construction works on the Dounreay-Mybster overhead line project have included the laying of over 26km of access roads; erection of 50km of fencing; installation of 101 tower foundations; construction of 97 towers; stringing of 6 conductors (wires) and an earth wire over approximately 28km; installing temporary scaffolding to protect road crossings; and restoration of land affected by the works. Further reinstatement work and final connection at all substations will follow next year in advance of energisation. Once the new 275 kilovolt line is in service, work will get under way to remove the old 132 kilovolt line between Dounreay and Spittal.

The top of one of the Dounreay-Mybster transmission towers being lifted...

...and carefully manoeuvred before being fixed in place by the Balfour Beatty construction team.