The wildlife on a site can present both constraints and opportunities to development. Based on the information collected these must be assessed and fed into decision making on the development’s layout and design.
Assessing the impacts on wildlife is a requirement due to their legally protection but also as there are local and national planning policies and government guidance to ensure that wildlife is protected and enhanced. This all feeds back to the need to stop the declines in biodiversity.
In the assessment and design of all development proposals, the mitigation hierarchy must be applied. This seeks to deal with potential impacts on biodiversity by considering ways to:
- avoid
- minimise
- mitigate
- compensate (on- then off-site)
- always look to enhance opportunities for biodiversity
On larger or more significant developments which require an Environmental Impact Assessment (EIA), it is necessary to also carry out Ecological Impact Assessment (EcIA). The CIEEM have produced guidance on how to do this.
With regards to protected species and ancient woodland and veteran trees, Natural England have issued standing advice that assists in decision making on how they should be considered.
In some instances, proposals will require a licence from Natural England which can only be sought following the granting of planning permission.
It is now a requirement for all development to achieve a measurable net gain in biodiversity. This requirement in in the National Planning Policy Framework (NPPF) and is now in the new Local Plan Policy DM34.
To assess and demonstrate that a net gain will be achieved, biodiversity accounting is used. First the baseline value of the habitats on site prior to development must be assessed (if a site has been cleared, aerial photos will be used to assess the type of habitat and the highest value for that type will be assumed). Then the value of the habitats which are proposed to be retained and included within a new development can be assessed. By comparing the baseline value with the proposed value it can be identified if there will be a net loss or a net gain. If a net loss is shown it will be necessary to provide Biodiversity Offsetting to enable the development to meet the policy requirement.
We are currently preparing a Supplementary Planning Document to explain how this will be done. Until this is available we expect developers to use the Warwickshire Matrix.