The economic benefits of a third runway ay Heathrow will be almost wiped out by the increased costs to the environment, analysis by the Liberal Democrats shows.
The government's own figures suggest that ministers have underestimated by several billion pounds the financial impact of the extra greenhouse gases produced by a third runway at the airport. Critics say the new figures show the government's support for the new runway is a "sham" and have demanded that plans to expand the airport are scrapped.
Simon Hughes, energy and climate change spokesman for the Liberal Democrats, which carried out the analysis, said: "It is time for the government to come clean on Heathrow. Ministers know the economic rationale for a third runway is a sham because their own figures prove it. By giving the green light to a third runway, the government has allowed hundreds of thousands more flights, creating a climate change disaster."
Ministers announced the Heathrow expansion plan in January, which could add another 220,000 flights a year at the west London site. The government said the climate change costs associated with the project would be £4.8bn through to 2080, which it said would leave an overall benefit to the UK economy of £4.4bn to £5.2bn. But the Liberal Democrats say this calculation was based on out-of-date figures.
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http://www.guardian.co.uk/environment/2009/sep/17/heathrow-third-runway-costs