Start with the consent route and submission date
BNG for NSIPs becomes mandatory in England for development consent order applications made on or after 2 November 2026. Defra’s guidance requires at least 10% biodiversity net gain. However, the relevant biodiversity gain statement and the project’s consent route remain central to the assessment.
This is a timely point to review responsibilities. The metric needs ecological evidence, but delivery also depends on land, design, construction, legal arrangements and long-term management. A spreadsheet cannot resolve those interfaces on its own.
Bring five decisions into one meeting
| Decision | Question for the team |
|---|---|
| Application strategy | Which consent route, gain statement and submission date are we working to? |
| Boundary and baseline | Have ecology and engineering reconciled the habitats affected by permanent and temporary works? |
| Design uncertainty | Which realistic alternatives remain, and who records their habitat implications? |
| Land and delivery | Are habitat proposals compatible with access, ownership, maintenance and the construction programme? |
| Evidence control | Who owns the coordinated plans, assumptions register and response to design changes? |
Defra distinguishes the BNG boundary from the order limits. Its guidance also requires a single metric calculation for the development, including disconnected components. Therefore, agree how separate work packages will feed one consistent evidence set.
Test the construction plan, not only the finished layout
Consider an illustrative scheme with a temporary compound beside the permanent works. The landscape drawing shows a restored area after construction. However, the construction team needs access, storage and a working strip that the ecology plan has not yet captured.
At that point, pause the document issue and reconcile the drawings. Record the expected impacts, restoration assumptions and any uncertainty. Ask the ecologist how the relevant metric rules apply. Avoid treating the word “temporary” as sufficient evidence that an impact can be ignored.
Make long-term delivery a present-day decision
Ask the future land manager to review the proposal while changes are still manageable. Can machinery reach the habitat? Will drainage maintenance conflict with its objectives? Who will act if monitoring identifies a problem?
Next, give each unresolved point an owner and a decision date. Keep legal securing, ecological design and delivery costs connected. This helps the project team recognise gaps before they become late changes.
BNG works alongside other environmental obligations. It does not replace the mitigation hierarchy, species protection or the environmental assessments needed for the consent route.
Discuss your project and evidence needs with ACP, or explore our BNG guidance and support.
Source and scope
England; checked 10 October 2026. Read Defra’s NSIP BNG guidance and the relevant gain statement. The commencement date is forthcoming at the time of publication.