CambridgePPF strongly support 20% Biodiversity Net Gain.
The overall intention of this policy direction is welcomed and supported. However, the detail of how the policy is worded to guide and enhance development will be critical and it is likely to require more than one policy to achieve this. It is, of course, appreciated that plan policies have to be developed further - some important issues are touched upon already and this is welcomed. As referred to in our general comments however, the first priority must be the protection and conservation of existing biodiversity and geodiversity interests. With this in mind we have a number of specific comments regarding the principles to underpin this objective. These should be reflected in future policies and/or supporting text in the GCLP:

• Assessment of impacts
All development affecting sites of biodiversity and geodiversity importance and interest should be subject to thorough assessment of impacts based on all relevant information and recent surveys.

• Mitigation and Compensation
The mitigation hierarchy should be followed for any development proposals. We are pleased to note that this has been referenced at section 3.5 of Topic Paper 3, i.e. ‘whereby harm should be preferably avoided, adequately mitigated, or compensated for as a last resort’. Acceptance of proposed mitigation as a way of making a development must be based on proof that it will work and should not be confused with compensation for irrevocable damage to an important site or interest. The distinction between mitigation and compensation is also important as the latter must require justification as an exception. Finally, all mitigation and compensation work should be properly secured in perpetuity if necessary. This is particularly important with regard to compensation. Compensation for permanent damage requires permanent recompense.

• Approach to harmful development
Any development that has an adverse effect (or risk of such effect applying the precautionary principle) should normally be refused. The supporting text with the current first proposals consultation indicates that exceptions will only be made where the public benefits significantly outweigh any adverse impacts. However, more clarity will be needed on how this will work in practice. Again, it is appreciated that the policy wording has still to be written. However, this is such an important issue that a clear statement of intent should be made now. If developments are proven to have an adverse effect or applying the precautionary principle, a risk of an adverse effect, then they should only be normally permitted when clear tests are applied. Arguably this should also include being satisfied that applicants have demonstrated that there are no less damaging alternatives they could pursue.

It is noted that the supporting text with respect of policy BG/BG states:
‘The policy will state that development proposals adversely affecting sites of biodiversity or geological importance will not normally be permitted. Exceptions will only be made where the public benefits significantly outweigh any adverse impacts.’

Clarification will be needed of what tests will be used to determine whether public benefits outweigh adverse impacts on important sites, because an approach solely on a case by case basis could risk a lack of consistency and consequent serious harm to biodiversity interests without sufficient justification. The level of public interest that would need to be demonstrated will also need to be commensurate with the level of interest affected. This level of test may be very high if for example, an internationally of nationally important interest is at risk.

The supporting text also goes on to say:
‘In such cases where development is permitted, we will require that the intrinsic natural features of particular interest are safeguarded or enhanced.’

Presumably the intention here is to safeguard or enhance any remaining features of interest after a damaging development is allowed.

• Biodiversity Net Gain
We strongly support a level of 20% Biodiversity Net Gain for the following reasons:
• Cambridgeshire is one of the most nature depleted counties in England, which is one of the most nature depleted countries in the world.
• Doubling nature in Cambridgeshire would only bring the county to the average for the UK.
• Cambridge Nature Network Report identified that existing habitats within 10km of Cambridge are too small and too fragmented to form a functioning ecological network. To achieve a functioning ecological network sustained effort and investment will be needed over the long term to make habitats better, bigger and more connected.
• Creating new habitats to replace those lost is not an exact science, meaning that some biodiversity offsetting will produce less biodiversity gain than expected. This variability is considered to be around 10%. Therefore a 10% BNG requirement does not guarantee that any individual development would actually achieve a net gain. Only a higher level of BNG, such as 20% has the prospect of achieving this.
• It should be noted that 20% BNG will not achieve the aspiration to double nature unless it were at 50%.
We have two additional comments at this stage. First, that biodiversity net gain must take account of the full value of an affected site including any interests that may have been deliberately damaged prior to a development occurring. Second, the use of planning conditions and obligations to secure the effective long-term management of any on or off site habitat creation referred to the policy supporting text is vitally important and is welcomed. Long term monitoring to ensure that any proposed biodiversity net gain delivers what it seeks to do is also critical. The Defra Biodiversity Metric focuses on the provision of habitat. This may be used to mitigate effects or secure enhancement for species directly affected by a development. However, to ensure that species affected will benefit from habitat provision requires careful monitoring - simply creating new habitat will not necessarily mean the species affected will use it.

We also look forward to seeing more detail on how the proposed policy will seek to secure wider environmental gains.

Cambridge Past, Present & Future welcome the recognition that “Designated biodiversity sites within and close to Greater Cambridge are being impacted by increasing numbers of visitors – an issue that needs to be addressed to protect these vulnerable habitats and the species they support. For nationally designated sites, Natural England have identified Impact Recreation Zones and recommend the application of Suitable Alternative Natural Greenspace standards to inform the quantity of green space provision required for people, to lessen the impacts on these nature sites. Greater Cambridge has relatively few nationally designated nature sites, but many locally designated sites. Ahead of the draft plan we will explore how we can best measure and mitigate the impact of development on these local sites.” In Cambridge Past, Present & Future’s research for the Cambridge Nature Network (http://cambridgenaturenetwork.org/ ) we identified that the creation of new accessible green space in Cambridgeshire has not kept pace with the increase in population over the past 20 years and this has been one of the main drivers of recreational impact on wildlife sites. In addition, many green space sites in Cambridgeshire are wetlands, meaning that although they might cover a large area, the amount of land that can actually be used by the public is often small or limited to paths. Unlike other counties Cambridgeshire does not have large areas of public access woodlands, downland/moorland/heathland or coastline. Our research also identified that generally, larger scale development (such as Cambourne) was providing larger areas of new greenspace but smaller developments were not and therefore it is these that are contributing most towards the problem as they have made up around 50% of the development in Cambridgeshire over the past 20 years. If the Local Plan is to be sustainable (ie not increase recreational impacts more than has already occurred) then ALL new development will need to make a contribution towards creating new Suitable Alternative Natural Greenspace (if none is created through the development). The Local Plan should set out how these contributions are to be collected and the amount that would be required per person. We refer you to the submission by the s106 Officer for South Cambridgeshire District Council who has calculated that this should be £498 per dwelling.