Final pylon removed from Olympic Park
A two-year powerlines project has been delivered on time and to budget with the removal of the final overhead electricity pylon from the Olympic Park site, the Olympic Delivery Authority (ODA) has confirmed.
ODA Chief Executive David Higgins said: “Removing the final overhead pylon from the Olympic Park site is a hugely symbolic moment as we begin to transform the skyline of east London for good.
“This £250m project, delivered on time and to budget, has created new jobs for local people and business opportunities for a range of companies and unlocks the Olympic Park landscape for the delivery of new homes, world-class sports venues and essential infrastructure.'
The powerlines project was started by the London Development Agency (LDA) in 2005, ahead of London's successful bid to host the 2012 Games. It was then handed over to be managed by the ODA, working with the LDA as well as EDF Energy and National Grid, the companies that own and operate the overhead lines. The project has involved three separate phases:
The tunneling phase
• Two 6km tunnels were built beneath the Olympic Park enabling the power needed for the Games and legacy developments to be carried.
• Four huge 40 tonne tunnelling machines were used.
• Tunnelling work was completed in 424 days
• The Olympic Park tunnelling accounted for 85 % of the UK’s tunnelling for that year.
• 200,000 cubic metres of spoil was created during tunnelling - enough to fill Wembley Stadium - the majority of which is being reused on the Olympic Park.
• The complex nature of the tunnelling process meant a series of obstacles were encountered during the project, including issues with soil contamination and encountering small ground movements and water ingresses beneath the surface of the Olympic Park.
• The tunnelling phase was delivered on time, on budget and with a good health and safety record.
The cabling phase
• Work began in June last year to install 200km of cabling in the tunnels – enough to stretch from London to Nottingham.
• More than 9,000 brackets were also installed to carry cabling along the tunnel walls, together with monitoring and ventilation equipment.
• The cabling phase of the project was completed on schedule in May, allowing testing and commissioning of the new underground equipment to begin.
• Power was then switched on underground last summer allowing work to remove the overhead pylons and powerlines to begin.
The pylon removal phase
• 52 overhead pylons were removed, producing 1,300 tonnes of steel which will all be recycled.
• 130km of overhead wires were removed.
A website has been created providing further information on business opportunities in the run up to the London 2012 Olympic and Paralympic Games. Visit http://www.london2012.com/get-involved/business-network
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