Pioneering engineering works completed ahead of schedule at Edmonton EcoPark

9 Apr 2021

North London Waste Authority’s (NLWA) plan for a new sustainable waste hub at Edmonton EcoPark – the North London Heat and Power Project (NLHPP) – has reached another major milestone as NLHPP contractor Barhale completes complex engineering works to make way for new recycling facilities.

Barhale has been appointed to divert the Angel and Chingford sewers beneath the future Resource Recovery Facility (RRF) and public Reuse and Recycling Centre (RRC). In March, two 15 tonne Tunnel Boring Machines (TBMs) arrived at the EcoPark each measuring 5.2m long and 1.5m wide. Using the TBMs, Barhale utilised an innovative technique to prepare the site for the main diversion.

David Cullen, NLHPP Programme Director said, “It is fantastic to see yet another construction milestone reached on the Project to deliver new waste management facilities in north London.”

“The highly specialised engineering works to divert the two Thames Water sewers is critical for the successful delivery of our nationally significant infrastructure project and thanks to the innovative construction methods used by Barhale, we are ahead of schedule on this phase of works”.

The TBMs were used to bore the tunnels for the new sewers as part of the sewer diversion. During the design phase Barhale identified an opportunity to fast track the programme and help deliver this essential project at a faster pace for north London’s two million residents. Barhale used an innovative tunnel drive shaft design to carry out the tunnel boring using two pipe jacks from a single shaft at the same time.

Pipe jacking is a method of tunnelling by which sections of pipe are laid behind the TBM cutting head and pushed under very high jacking forces to drive the tunnel forward laying the new sewer at the same time. Using this innovative approach enabled Barhale to recycle water through both TBMs cutting approximately 65% of the water required to complete the task.