The proximity principle in BNG prioritises enhancing biodiversity as close to the impact site as possible. For developers, this means the first preference should be to implement BNG measures directly on the development site, ensuring that local habitats and ecosystems benefit directly from the improvements. If onsite BNG is not feasible, the principle then guides developers to seek offsite opportunities nearby, either within the Local Planning Authority area or the National Character Area the development is within. This approach helps maintain ecological integrity and ecosystem services within the local community, ensuring that biodiversity enhancements are relevant and beneficial to the area most affected by the development. Adhering to the proximity principle helps minimise ecological impacts and promotes sustainable development practices.
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The spatial multiplier in BNG is used to account for the distance between the impact site and the location of offsite biodiversity enhancements. For developers, this means that if BNG measures cannot be implemented onsite and must be done offsite, the further away the enhancement site is from the development, the higher the multiplier applied.
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