East West Rail Ecology Mitigation


The railway infrastructure between Oxford and Bicester upgrade, as part of Network Rail’s wider East-West Rail Link, will re-establish a direct connection between Cambridge and Oxford. The Oxford to Bicester section, operated by Chiltern Railways will be upgraded from a single-track bi-directional line, to two lines capable of supporting trains travelling at faster speeds. As well as embankment works, the scheme also requires the provision of road bridges and additional siding works. Along the route of the line are extensive ditch networks and these sit within a landscape well known for its widespread populations of great crested newt, a European Protected Species (EPS).

Our role in the project

Our first task was to critically review existing great crested newt baseline survey reports to establish that previous surveys would inform future EPS licence applications to Natural England. As adviser to ERM (Environmental Resources Management) and the end client (Network Rail and Chiltern Railways) we secured six EPS mitigation licences at different locations along the line where separate great crested newt metapopulations were identified. The purpose of the licences was to permit lawful disturbance to great crested newts that were using ditches, ponds and terrestrial habitat on and adjacent to the railway embankment, thereby allowing the proposed works to proceed.

To secure the licences it was necessary to demonstrate to Natural England that the conservation status of great crested newts would be unaffected by the development, and that reasonable measures would be set in place to avoid killing or injury of great crested newts. Accordingly, a mitigation strategy was developed which firstly included the creation and enhancement of ponds and the construction of hibernacula and refugia to replace those to be removed or damaged. Once we secured the licences, newt fencing was installed across the development footprint, spanning over 21 km of line-side and adjoining fields. Amphibians are now being captured and excluded from the development footprint, and translocated to the previously created receptor areas.

To undertake a translocation of this scale requires careful planning, attention to detail and an understanding of the wider project needs. We assembled and co-ordinated a large team of field assistants to check pitfall traps, search for amphibians by torchlight, and conduct fingertip and destructive searches of potential

refuges within the development footprint. All work was undertaken in accordance with the necessarily stringent health and safety protocols demanded of workers operating near a live railway.

Adapting to change

Throughout the life of the project, the complexities of ownership and responsibilities in connection with the project required extensive liaison with Natural England, tenants, landowners, clients and other stakeholders. Allocating an experienced ecologist dedicated specifically to the project has been essential in maintaining consistency and timeliness of sound advice to stakeholders.

The weather conditions presented a significant challenge. The hot, dry summer and early autumn of 2013 meant that amphibians were reluctant to move during these times, and we needed to quickly respond and adapt our methods of trapping and reporting to Natural England, in response to the numbers of great crested newts and rates of capture. At one site, over 2,000 great crested newts were captured, many of these only being captured towards the end of the trap-out, which lasted for over 100 days.

An intensive period of trapping in October 2013, when conditions were most favourable, led to a positive outcome, with the trap out completed at four of the six sites and handed over to development. Meanwhile a strategy has been devised through agreement with Natural England and the client for the remaining two sites, which will enable their timely trap-out in early spring 2014 so that the rest of the development can proceed.


Network Rail and Chiltern Railways via Environmental Resources Management

Infrastructure, Projects, South East