The three runway options, according to the Heathrow plan are:
NORTH WEST - £17 billion - completed by 2026 - affect Harmondsworth and Longford
A 3,500 metre-long runway to the north west of the airport with passengers accessing it from a new Terminal 6 and an extended Terminal 2.
The building of the runway would affect the villages of Harmondsworth and Longford with 950 properties facing demolition.
Part of the M25 would have to be put in a tunnel. The runway would cost £17 billion and could be completed by 2026.
SOUTH WEST - £18 billion - completed 2029 - affect Stanwell Moor
A 3,500 metre-long runway covering an area of reservoirs and needing the compulsory purchase of properties in Stanwell Moor and 850 possible demolitions. Passengers would access via T6 and an extended T2.
The construction would be complex and challenging and would take longer and be more expensive than the other options. It could be ready by 2029 at a cost of £18 billion.
NORTH - £14 billion - completed 2025 - affect Sipson, Harlington and Cranford Cross
This would be the quickest and cheapest option but would allow only 700,000 flights a year with a runway only 2,800 metres long. Passengers would access via an extended T5 and extended T2.
A total of 2,700 properties could be demolished, with the villages of Sipson, Harlington and Cranford Cross affected. This runway could be finished by 2025 at a cost of £14 billion.
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Mayor of London Sadiq Khan is backing the scheme.
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