"It will be the biggest private contract ever offered for a new British road. The government's Highways Agency is offering £1.6bn to a private consortium to widen around 60 miles of the M25 to four lanes in each direction. It will take five years to build, will swallow tens of thousands of acres of greenbelt land, encourage yet more people to travel by car - and it will end up costing the taxpayer more than £5bn." (Quoted from article)