Cockfosters De-vegetation, London

As part of the Piccadilly Line Upgrade, Cockfosters depot was identified to be expanded to increase the sidings capacity for the increased number of trains and carriages.

Prior to this, a large area of land (7500m2 to be precise!) adjacent to a disused siding needed to be cleared of trees and ground vegetation, to allow for surveys and design to be completed prior to the main construction work. The client had completed ecology surveys of the area to be cleared, the only requirement was to complete the vegetation clearance prior to bird nesting season.

Unfortunately, due to the fast approaching bird nesting season, we were under some pressure to get this completed which resulted in the vegetation clearance being completed in a traditional manner with chainsaws and chippers. Had there been time to complete the large plant approval process, our preference would have been to mechanise the clearance using excavators fitted with tree shears, grabs and the use of whole tree chippers to process the arisings and for the chipped arisings to be sent for bio mass recycling.

The whopping area of 7500m2 was cleared in six weeks by an eight man team with most of the work achieved during week days, when then trains were running, and a final week of nights to clear the trees adjacent to track during engineering hours. The trees were straight felled where possible but trees adjacent to third party land and track were climbed and felled in sections.

The cordwood left on site will be cleared at a later date, as part of the construction work once the design has been completed. The intention is to recover the cordwood and send it off for biomass processing as a carbon offset of the tree clearance.

Wonderful work by our teams as always. We hope we can be part of the main construction!