The work involved removing 52 overhead pylons with 130km of overhead cabling.
Two 6km tunnels were built beneath the Olympic Park enabling the power needed for the Games and legacy developments to be carried underground along 200km of cabling. This part of the contract was carried out by Murphy.
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.”
The powerlines project was started by the London Development Agency 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.