As part of the planning permission for the proposed runway extension at London Ashford Airport, at Lydd in Kent, there were a number of ecological pre-commencement conditions. EHM Ltd was contracted to ensure all these conditions were adequately discharged to ensure the planning permission could be implemented. The conditions included carrying out a range of updated ecology surveys across the airport site and surrounding area as well as compiling detailed mitigation strategies.
The airport is located within the Dungeness peninsular, the largest shingle peninsular in Europe, a large expanse of shingle habitat laid down by geological processes tens of thousands of years ago. This area is of international conservation importance for its geomorphology, plant and invertebrate communities and birdlife. This is recognised and protected mostly through its conservation designations as a national nature reserve (NNR), a Special Protection Area (SPA), a Special Area of Conservation (SAC) and part of the Site of Special Scientific Interest (SSSI) of Dungeness, Romney Marsh and Rye Bay. As the site is located within statutory protected areas all the survey methodologies and mitigation strategies had to be agreed with Natural England and the local council.
Species surveys included; Great Crested Newts, Reptiles, Bats, Botanical, Moths and water vole. Specialist surveys for rare lichens were also conducted working in partnership with experts from the London Natural history Museum. EHM were also responsible for creating suitable mitigation plans for the number of protected and notable species found across the airport. Due to the amount of protected species and habitats on the site the mitigation strategies were complex and had to be agreed with Natural England and the council ecology team. EHM devised suitable strategies to meet the requirements of the airport and satisfy the expectations of Natural England and the council ecologists.
The work involved extensive site visits and meetings with different stakeholders. It also involved co-ordinating a number of different specialist surveys and a team of ecologists working towards a dead line. The mitigation plans needed to consider a wide range of species and the impacts of one species strategy on another species to avoid negative impacts and legislation implications.
As part of the proposed water vole mitigation strategy EHM oversaw the creation of a number of ditches at the Airport. The works were all carried out inside the Dungeness and Romney Marsh SSSI which involved close liaison with Natural England to ensure the works were carried out without causing any negative impacts to the other species and habitats of the SSSI. The location of the ditches was selected, following detailed surveys and discussions, as a series of ditches that had become silted up. Works were carried out to remove all the silt to re-open the ditches without impacting the underlying geomorphology.
By excavating these once extant ditches the impact to the buried morphology was mitigated. Following a suitable impact assessment and agreeing a construction method statement with Natural England work was able to begin. Where the ditches were to be excavated some shallow depressions still existed that retained water after heavy rainfall. Therefore distinctive marginal aquatic vegetation had developed alongside the grassland sward. The ditches were excavated in such a way to ensure the aquatic vegetation was able to be re-used on the newly excavated ditches. The excavated material was banked up on top of the excavated ditches with the saved grassland turves placed on top along with any other remaining top soil. This created a habitat that had established vegetation within a short period of time. EHM provided all the necessary plant, tools, labour, materials and ecological support for this project.
The work at London Ashford Airport required a variety of ecological and project management skills. EHM worked hard to deliver the variety of projects on time and to the satisfaction of all the stakeholders involved. If you require any further information or help with a similar project please do not hesitate to contact us.