London Wildlife Trust is disappointed – but unsurprised – to see the Government exhibit its shifting and fickle attitude to the environment by giving the green light to build a third runway at Heathrow Airport on World Environment Day.

This expansion will be disastrous for the environment close to the airport, and for the wildlife assets that will be destroyed or damaged by the expansion westwards into the Colne Valley.

It was only in March this year that the Trust officially opened Huckerby's Meadows, a new nature reserve situated just metres from Heathrow's existing northern runway, with support from the airport's operator.

A third runway at Heathrow means:

• Building on 906 hectares (2,238 acres) of land, including 432 hectares (1,067 acres) of Green Belt land;
• Taking land within three sites of nature conservation importance, including the Lower Colne Site of Metropolitan Importance;
• Losing 35 hectares (86 acres) of woodland;
• Affecting 13km of river;
• Threatening a population of pennyroyal, a Nationally Scarce relative of mint.

There are 39 wildlife sites within 5km of the proposal, including the South West London Water Bodies Special Protection Area (SPA) - supporting  internationally important numbers of over-wintering gadwall and tufted duck - and two Trust nature reserves; Huckerby’s Meadows and Frays Island & Mabey’s Meadow. There will be significant implications for potential birdstrike at the SPA site.

The loss of Green Belt will result in the single largest reduction of London’s Green Belt since it was designated in the 1950s. Significant changes to water courses, including the River Colne, will also be required, with potential impacts on migratory fish such as eel and brown trout.

The Government's decision to back Heathrow Airport's expansion directly contradicts commitments laid out in its recent 25-year environment plan. Local air pollution levels, already breaching legal limits, risk being further worsened if this proposal is built.

Transport Secretary Chris Grayling stated that this third runway will only be granted planning consent if it meets the UK’s air quality commitments, but given the Government’s record to date there is every reason to believe this promise will not be kept. By the time planning consent is granted the UK will likely no longer be subject to EU air quality directives.

It is also doubtful that the UK can effectively meet its carbon emission targets and claim to be a world leader on climate change adaptation after allowing 700 additional flights each day from Heathrow.

We urge MPs to reject Heathrow's expansion in the forthcoming vote on the proposal, likely to be on 11th July.