Biodiversity Net Gain

Since Biodiversity Net Gain (BNG) has become adopted as local planning policy, most planning applications now require a BNG report. We are fully trained and up to date in this area, and we now will map most sites to UK Habs standard so that we can run Defra Metric 3.1 to obtain a BNG score.

There are many areas of concern at present. One being the imposition of BNG on small sites, where it is just not fit for purpose: it will not accept wildlife boxes (such as swift boxes) as providing any value, and options such as woodland or scrub creation just is not viable. Using the Small Sites Metric can create a net gain from planting just one tree, which is in no way an improvement in comparison to using integral bat and bird boxes.

Another main issue is that some sites cannot achieve a gain whatever you do. This may be where a greenfield site has been granted permission to provide high density housing; the planning authority may condition a BNG report, when a net gain is impossible. The developer then has no option but to buy additional land for off-site enhancement, in order to offset the loss. By the end of 2023, the secondary legislation should be in place which will allow an offet payment to be made to the planning authority’s ecology bank, instead of using additional land, but at the moment developers can find themselves stuck by the demands of the policy without the means to go forward in a meaningful or pragmatic way.

BNG reports are full of anachronistic elements; simply changing the target condition of tree planting (diameter to be acheived in 30 years) can switch a loss to a gain, without any genuine change in input. There are serious concerns about how these reports will be policed, especially where large payments or costs can result from simple manipulation of codes within the Metric. We hope that future versions will include failsafes to ensure a level playing field.