National Grid overhead powerline diversion work in Colne Valley now complete

What we are doing

National Grid, and its contractor Morrisons Energy Services, has completed the overhead powerline diversion work in Colne Valley for HS2 Ltd to allow for the build and operation of the new railway. This ends a project which began in 2019 and has involved rerouting and raising the height of a line of electricity pylons which the railway will pass under.

To achieve safety clearance five existing pylons, conveying a 275kV high voltage overhead line across Denham and Hillingdon, were dismantled. Six taller pylons were built in new locations to divert the line across a lower section of the railway at a suitable crossing point. The overhead line was then connected back up to the existing network.

The final piece of work this year involved removing the River Colne temporary bridge and associated working areas/abutments that had been in place in Denham Country Park. To comply with great crested newt licences work didn’t start until Spring 2024. On 26 March 2024 National Grid began removing the remaining temporary bridges. The final bridge was removed 22 May 2024. Reinstatement of the area followed.

National Grid have engaged closely with stakeholders throughout the works. Full demobilisation of the project site office and the yard area off Harvil Road began mid-May and is now complete.

Should you have any questions about  the National Grid work or their role on HS2, please call their Community Relations team on 0800 073 1047. They’re available daily from 7am-7pm. Alternatively, you can email [email protected]

Find out more about

• Buckinghamshire and Oxfordshire

If you have a question about HS2 or our works, please contact our HS2 Helpdesk team on 08081 434 434 or email [email protected]