The report suggests the environmental impact, especially on wildlife habitats, of an Isle of Grain airport could cost up to £2bn to remediate.
The report says a new airport on the Hoo Peninsula would “radically and irreversibly” alter the landscape.
An Estuary Airport would, says the report, adversely affect several international nature conservation sites, including the Thames Estuary Marshes special protection area (SPA), and that as a result, to be built, would need to demonstrate that there are no feasible alternatives, such as expanding an existing airport.
It suggests that identifying suitable sites to move the wildlife displaced by a new airport to would not be trivial, and estimates the cost involved to be between up to £2bn.
The report also notes that the Isle of Grain is known for its remoteness. There may be a message in that too. Remote airports are not always popular with travellers.