There are specific biodiversity net gain provisions for applications to vary conditions to existing permissions under section 73 to reflect the fact, while a section 73 permission is a new permission, it is linked to an earlier planning permission.
An application to vary a condition of a planning permission under section 73 which is made after 12 February 2024 (the commencement of the statutory framework for biodiversity net gain) is not in scope if the original permission (to which the section 73 application relates) was either granted or the application for the original permission was made before this date.
Section 73 applications are not required to be accompanied by the minimum information requirements such as the pre-development biodiversity value of the onsite habitat for biodiversity net gain set out in Article 7 of The Town and Country Planning (Development Management Procedure) (England) Order 2015. This baseline information would have already been provided with the application for the original permission.
If a planning permission granted under section 73 does not affect the post development value of the onsite habitat (and in the case of a site containing irreplaceable habitat any arrangements made to compensate for any impact) specified in an approved Biodiversity Gain Plan for planning permission to which the section 73 permission relates, the earlier plan is regarded as approved for the purpose of the new permission granted under section 73. In this circumstance, a new Biodiversity Gain Plan is not required to be submitted and approved prior to the commencement of the development subject to the section 73 permission.
However, if any conditions attached to the new planning permission granted under section 73 do affect the post development biodiversity value, then a Biodiversity Gain Plan for the new permission must be submitted and approved prior to the commencement of the permission.
A section 73 permission cannot be used to vary or remove the biodiversity gain condition.
What are the implications for biodiversity net gain if a section 73 permission varies a condition related to a permission for phased development?
The statutory framework for biodiversity net gain has been designed to take account of the fact that, for a long term phased development, a section 73 permission can sometimes be granted after the original permission has been commenced to change the conditions related to development, including future phases, and this section 73 permission is a separate permission to the original permission.
In the first instance, if a section 73 permission for phased development does not affect the post-development value of the onsite habitat of the entire development or affect irreplaceable habitats (including any compensation arrangements) as specified in an earlier plan, the Overall Biodiversity Gain Plan for the original permission is regarded as approved for the section 73 permission and a new Overall Plan would not need to be submitted and approved. Similarly, any Phase Plan which has been approved would continue to apply as the post-development value for the development or irreplaceable habitats has not been affected.
However, if the section 73 permission affect the post-development value of the phased development’s onsite habitat or its irreplaceable habitats, a new Overall Plan would be required to be submitted and approved to ensure the biodiversity gain objective will be achieved.
The content and approval matters for this Overall Plan are similar to that of an Overall Plan for the original planning permission, except that additional information must be provided in the Overall Plan about the post-development biodiversity value of the onsite habitat of a phase which has already begun and the planning authority must be satisfied that this value is at least the value of specified in the Phase Plan most recently approved for that phase (unless there has been a section 73 permission which has affected this value.)