Lower Thames Crossing

Tuesday 15th March 2016

Computer generated image of the Essex tunnel portal (Highways England)

Highways England is currently consulting on proposals for a new crossing over the River Thames. They argue that a new crossing is needed to reduce congestion at the existing Dartford crossing and unlock economic growth, supporting the development of new homes and jobs in the region.

The favoured option, Option C, would consist of a bored tunnel crossing the river from Gravesend in Kent to Tilbury in Essex.

The Trust has fundamental concerns regarding the impact of these proposals on wildlife. We accept that the choice of a bored tunnel avoids direct impacts on the internationally important wetland and coastal habitats of the Thames Estuary Ramsar/Special Protection Area. However, the location of the tunnel portal to the north of the crossing (and, in particular, the potential works area associated with the tunnel portal) would destroy an area of historic coastal grazing marsh and Local Wildlife Site (Goshems Farm), which supports a diverse range of Red Data Book invertebrates and is likely to provide functionally linked habitat (e.g. high tide roost) for the qualifying bird species of the SPA. The site may also support protected species such as water voles.

There are three route options for a new road link across south Essex to the M25 and there would be additional impacts on biodiversity from the 3 route options as follows:

  • Route 2: impacts on an area of ancient woodland, a further 5 local wildlife sites and 5 areas that support UK BAP priority habitats. Chadwell Wood ancient woodland may also be affected.
  • Route 3: impacts on a further 3 local wildlife sites and 4 areas that support UK BAP priority habitats. One of the affected local wildlife sites, Low Street Pit, is an important site for rare Thames Terrace invertebrates and is likely to provide important high tide roosting habitat for SPA qualifying bird species.
  • Route 4: impacts on 6 areas of ancient woodland and a further 8 local wildlife sites. LWS containing ancient woodland may also be affected by changes in air quality (increase in nitrogen) from increased traffic flows.

The northern section of Route 4 would have a significantly greater impact on biodiversity than either of the other 2 route options. Highways England has already stated a preference for Route 3.

Map showing Option C (Highways England)

All 3 link road options will result in loss or damage to important habitats and fragmentation of the habitats that remain. Surveys have yet to be undertaken, so the full impact on biodiversity has not been assessed. Noise impacts beyond a narrow zone close to the road have not been considered; the cumulative impacts of noise, road lighting and the visual intrusion of ‘man- made’ infrastructure will combine to reduce the remoteness and wildness of the landscape and its tranquillity.

The Trust believes that poorly planned and assessed road developments can have a negative impact on the natural environment (sites, habitats, species and ecosystem function). We believe that road developments should be considered as part of a sustainable transport strategy for England, which must be strategically planned and fully integrated with conservation objectives and the land use planning process. This should:

  • prioritise environmentally sensitive maintenance and improvement of the current road network over new road schemes
  • reduce the need to travel, for example through well designed towns, cities and neighbourhoods, and improved transport technology
  • promote less carbon intensive forms of transportpromote reductions in private vehicle use in order to reduce traffic levels, fuel consumption and vehicle emissions, including fiscal measures and car share schemes
  • minimise dependency on private vehicle use by increasing and improving public transport and active travel routes, which are well connected to essential services
  • promote walking, cycling and other forms of active travel and promote active travel routes which are easy, safe and attractive to use

We believe there is a need for an integrated, sustainable transport strategy for England which seeks to achieve accessibility that results in the least damage to the natural environment. Transport planning should be integrated within the overall planning policy framework at national, sub-national, county/unitary and local levels. This should encourage proactive, environmentally sensitive management and maintenance of existing transport networks and associated green infrastructure, in a way that contributes to the development of an ecological network. There should be a presumption against any transport development which would damage or threaten habitats or species of principle importance; and/or which degrades or disrupts the function or recovery of any identified ecological network or Living Landscape.

If the proposals for a Lower Thames Crossing are adopted, we will seek appropriate mitigation and compensation for the lost or damaged habitats and opportunities to enhance, restore or create new habitats as part of the local ecological network.

We will also seek to ensure that all opportunities are taken to:

  • reduce environmental damage through good design
  • secure net biodiversity gain by creating, enhancing and managing ecological networks, associated wildlife habitats and key species populations
  • ensure any landscaping is appropriate to the natural character and ecological functionality of the area.

We will also seek to impress upon the Government and Highways England the importance of species recording and long-term monitoring. This would be essential in relation to both the impact of the new road and the enforcement and implementation of any mitigation/compensation measures undertaken.

A public consultation on the Lower Thames Crossing proposals is open until the 24th March, and can be found here: http://www.lower-thames-crossing.co.uk/