From
http://www.telegraph.co.uk/business/...rt-for-london/

Quote:

Heathrow's controversial proposal to build a third runway would place a
£16bn burden on Transport for London, the agency has said, as it would
require upgrades to the road and railway networks that service the airport.

TfL said Heathrow had "substantially underestimated" the impact of the
extra runway, as it released a figure eight times higher than the £2.2bn
that the airport had calculated.

The transport authority instead estimates that the development, which could
lead to heavier congestion on London's roads, buses and trains, will have a
£18.4bn price tag.

Heathrow has previously promised that £1.2bn would be raised through public
contributions, with the airport spending another £1bn, leaving a shortfall
of more than £16bn.

.... continues