Decision details

To agree Cheltenham Borough Councils response to the Department for Environment Food & Rural Affairs (DEFRA) consultation on the proposed introduction of a targeted exemption for brownfield residential development from Biodiversity Net Gain (BNG), confirming that the Council does not support the proposed exemption or associated definitions.

The proposed exemption risks undermining the fundamental purpose of BNG by removing a significant proportion of development from biodiversity requirements. This would be particularly detrimental in urban areas such as Cheltenham, where urban ecology could be significantly affected.
Evidence demonstrates that:
• Brownfield sites can support habitats and species of significant ecological value and can represent some of the most biodiverse habitat in urban areas, despite significant historic losses.
• Natural England datasets identify Open Mosaic Habitat on Previously Developed Land (OMH) as a priority habitat under Section 41 of the Natural Environment and Rural Communities Act 2006, supporting rare and threatened species.
An exemption based on land classification rather than ecological evidence risks overlooking sites of genuine biodiversity importance and is inconsistent with the evidence-led approach underpinning national planning policy. It also risks bypassing the mitigation hierarchy (avoid, minimise, mitigate, compensate), which the National Planning Policy Framework requires to be applied, and supports a “nature-first” approach.
The proposal would likely:
• Reduce on-site biodiversity delivery
• Increase reliance on off-site provision
• Displace biodiversity benefits away from development sites and urban areas
There are also concerns regarding the cumulative effect of exemptions, which could weaken the BNG framework and reduce contributions to the emerging biodiversity market.
This has wider implications for sustainable placemaking, as urban green infrastructure delivers multiple co-benefits including improved health, wellbeing, climate resilience, and quality of place.
In preparing the response, officers have reviewed and support the representations made by the Chartered Institute of Ecology and Environmental Management (CIEEM).

1. Not responding to the consultation - Given Cheltenham’s urban context and the potential local impacts, it was considered appropriate to allocate officer time to preparing a response.
2. Supporting the proposed exemption - Evidence demonstrates that brownfield sites can hold significant biodiversity value, and the exemption would reduce opportunities to secure biodiversity net gain, particularly in urban areas.
3. Introducing a conditional or threshold-based exemption (e.g. based on site size or proportion of previously developed land) - Such metrics are not reliable indicators of ecological value and could result in the loss of important habitats.