Biodiversity

The Environment Act 2021 mandates that new developments achieve a 10% net gain in biodiversity. This means that development must create more biodiversity rather than detract from it. The biodiversity value of habitats on a site are collectively measured and referred to as biodiversity units (BU).

Our nature team assesses the biodiversity baseline value of a site using the Statutory Biodiversity Metric calculation tool and works closely with design teams to determine the value of the site proposals. Through an options appraisal, we offer recommendations to help retain and enhance the site’s biodiversity, aiming to meet the 10% biodiversity net gain (BNG) requirement on-site. Where 10% cannot be achieved on-site, we can provide a BNG off-site market analysis (more details below).

This feasibility assessment and options appraisal is intended for the design stage of a project. When the design is fixed, a final BNG assessment will be conducted and submitted as part of the planning application, along with a copy of the metric (as required by the legislation).

Development sites that are adjacent to watercourses are likely to need a river corridor assessment. This is similar to a preliminary ecological appraisal, but includes assessment of watercourse specific features. For development projects that are adjacent to, or within 10m, of a watercourse and are required to deliver BNG, a specific MoRPh survey may be necessary.

Our nature team is experienced in conducting BNG assessments which include MoRPh, and works with design teams to explore options for delivering watercourse based BNG.

With the updated National Planning Policy Framework (NPPF) and Government BNG mandate, it’s becoming increasingly necessary to establish how new development results in measurable gains for biodiversity. The emerging new London Plan also embeds requirements for BNG with an added need to meet improvements in green space coverage using the Urban Greening Factor (UGF) tool.

Our nature team is experienced in the delivery of UGF and BNG both at the corporate and project level. We help provide policy compliance advice, undertake calculations and inform design interventions to help maximise improvements.

Section 105 of the Environment Act requires responsible bodies to produce a local nature recovery strategy (LNRS). The purpose of the LNRS is to identify locations in which to create or improve habitat most likely to provide the greatest benefit for nature and the wider environment. They also help communities map out the action needed in their area to restore nature, working closely with local stakeholders.

Greengage supports local authorities in the development of LNRS and helps landowners explore opportunities for BNG delivery within LNRS areas.

Where the mandated 10% BNG cannot be delivered on-site, Greengage can prepare an off-site compensation market analysis to explore suitable off-site provision. BNG requires certain habitats to be replaced on a like-for-like or better basis, so this market analysis explores the suitability of off-site compensation providers to meet the specific needs of the project.

BNG requires all significant on-site gains and all off-site gains to be subject to a 30-year legal commitment, securing appropriate monitoring and management. We work closely with landscape architects, land and estate managers to develop management plans that meet the statutory requirements and which provide the required gains in the long term.

On-site BNG that is not considered significant will need to be managed appropriately. Greengage works closely with landscape architects to ensure that management prescriptions are suitable for ecological features such as ‘pollinator patches’, bat boxes and biodiverse green walls.