Aviation Project

Direct land take
The proposed airport on its own would occupy some 20 km2 / 8 sq. miles of land, without any new roads, railways, river crossings or ancillary development. This note only includes protected land, but a considerable area of farmland, a large proportion of which is being converted from arable to grazing marsh under an Environmentally Sensitive Area Scheme.

The development area includes all of Allhallows village, most of High Halstow village, the hamlet of St Mary's Hoo and some of Lower Stoke. It extends from Cooling in the west almost as far as Yantlet Creek in the east, and from High Halstow up to and just beyond the north coast of the peninsula.

In order to avoid flood risk, it is envisaged that the area would be land-raised in order to provide a level platform some 15m / 49ft above sea level.

Land take of protected sites
If the airport is developed as shown in the consultation document, it will destroy 5.25km2 / 2 sq. miles of land of special scientific interest, including virtually all the Northward Hill SSSI and SSSI land at Cooling, Halstow and Allhallows Marshes.

Within this area, it would also destroy 4.7km2 / 1.8 sq. miles of the Thames Estuary and Marshes Ramsar Site, and 2.8km2 / 1 sq. mile of the Thames Estuary and Marshes SPA.

The airport will result in the complete loss of the Northward Hill National Nature Reserve and the associated RSPB reserve.

Although the proposed airport will not directly affect the RSPB's new reserve at Cliffe Marshes, the airport proposal is accompanied by a proposal for a new Thames crossing immediately south of this reserve.

Indirect effects on surrounding marshes
The government's consultation document notes that the presence of the airport would probably increase the risk of flooding over the peninsula as a whole. It is not clear from the document whether this flooding is expected to result from the River Thames over-topping the sea-wall, or from changes to groundwater levels and flows in the dyke systems. Whatever the cause, this could have a devastating effect on the marsh wildlife, as well as a substantial impact on homes and farmland.

The rich wildlife of the Hoo Peninsula depends on the complex mix of dry ground, permanantly wet ditches, seasonally flooded areas and wet grasslands. Excessive flooding could result in the loss of nesting areas used by birds, and of dry ground used by rare insects and plants. It could also lead to increased salinity in many of the ditches, so that these become unsuitable for many rare, aquatic species.

Changes in existing water flows and groundwater levels, and interruptions of slow-flowing streams and dykes might have the opposite effect, and lead to areas drying out. Much of the important wildlife of the marshes is dependent on wet ditches, ponds, and seasonally wet fields, and would be lost if these dried out.

Impacts on rare species
The Hoo Peninsula is home to some fifty species of plants and animals which are so threatened that the UK government has included them in its own Biodiversity Action Plan.

Many of these species will lose a huge area of their habitat if the airport goes ahead. Even the remaining populations on land outside the airport itself are likely to be badly affected as their habitat is broken up into smaller and more isolated fragments.

For more information of the species which would be affected, see the accompanying sheets.

Aircraft and bird-strike
Medium to large size birds can pose a deadly risk to aircraft. Even a pigeon striking an aircraft at high speed can result in the loss of the aircraft. This is such a serious problem that the Civil Aviation Authority opposes the creation of new wetland habitats (which might attract wildfowl) within 13km of any existing aerodrome.

Yet in this case, the government is proposing a major new airport in the middle of an area which attracts tens of thousands of wildfowl and waders every winter. Either there would be an enormous safety risk to all those travelling to or from the new airport, or there would be pressure for all wildfowl and waders to be excluded from the whole of the Hoo Peninsula. It is worth noting that the RSPB's new reserve at Cliffe is well within the CAA's exclusion radius.