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Biodiversity Solutions

Ecological Impact Assessment (EcIA)

Hay meadowUnder an Environmental Impact Assessment (EIA), an Ecological Impact Assessment (EcIA) is usually required. It can be used on any development project and can be used to predict and monitor significant ecological impacts. The EcIA should also be flexible and will evolve as more ecological information presents itself during the development.

It is good practice to consider the amendment of preliminary designs as ecological information is provided to avoid significant harm to biodiversity both on and off site. Ecologists are able to support this adaptive approach, helping monitor work programmes and ensure species are considered at all stages. We follow the avoid-mitigate-compensate hierarchy during the EcIA process.


A number of stages are involved in an Ecological Impact Assessment

  1. Scoping

This first step involves a desktop study to gather data on the site, its ecology and relevant legislation and policies, the information from which is used to inform the extent and scope of the work under the full EcIA. An Extended Phase 1 habitat survey is also conducted.

  1. Detailed Ecology Surveys (including Protected Species Surveys)

If the initial scoping exercise highlights any sensitive or protected species which may be adversely affected by a development, the next stage would be to conduct on site detailed ecology surveys by appropriately qualified and, if necessary, licensed individuals. This is often seasonal, so it is crucial that the necessity of these species surveys is identified as early as possible in the planning process to avoid delays.  Where necessary ecologists would work with qualified arboculturists.

  1. Evaluate Nature Conservation Value

The importance of the site, its habitats and species is then assessed in this next stage of the EcIA process, using the data and survey results collected during the first two stages. The different parts of the site are given a value, based on published guidelines, to ascertain its ecological value.

  1. Assessment of Impact

The survey data is then interpreted to allow the ecological impact of the development to be determined. If, for example, habitat loss will occur, this is an impact that will need to be examined, as well as if habitat will be created. Ecologists therefore examine the overall impact, whether it is likely to be positive or negative and also the scale of the impact (large or small). From this, it is possible to consider the significance of these impacts based on the value of the habitat that is being affected and how much of it will be affected.

  1. Mitigation

Once likely impacts have been identified, it is then possible to suggest measures that can be taken to avoid, reduce or compensate for these impacts. It may be legally required to avoid impacts, such as in cases where protected species are likely to be killed as a result of the development. Where there is no legal requirement, there may still be a need for mitigation in order to satisfy local planning policies and best practice guidelines.

  1. Residual Impacts

Effects of the development on biodiversity and species richness is then ascertained, in light of any proposed mitigation measures. This is used to determine the final (residual) impact.

  1. Environmental Statement

The results of our EcIA can then be included in an Environmental Statement. This presents all the relevant information on the likely ecological impact of the proposed development, allowing decision makers to make a fully informed choice.