When can you use the Small Sites Metric for your project?
3 Nov 2024 | 5 min read
- As of April 2, 2024, the Small Sites Metric (SSM) tool, a simplified version of the Statutory Biodiversity Metric calculation tool was made available for 10% biodiversity net gain (BNG) planning.
- A project must meet both size and habitat restrictions to qualify for use of the SSM.
Like large-site developers, smaller-site developers must answer the 10% biodiversity net gain (BNG) requirement in the UK government’s Environment Act 2021. Small developers now also must submit their project and their plan to support 10% BNG to local planning authorities (LPAs).
The benefits of working with the Small Sites Metric include a streamlined biodiversity assessment: Developers simply select from the brief list of habitats within the tool. There is no requirement for an individual with ecological training or experience (“competent person”) to deliver a condition assessment.
But the project must qualify to use the Small Sites Metric as per parameters identified in the Town and Country Planning Order 2015.
Residential and commercial restrictions
It is always acceptable to use the Statutory Biodiversity Metric calculation tool, but the Small Sites Metric can only be used for:
- Sites that do not have priority habitats. If priority habitats are present, you must use the Statutory Biodiversity Metric.
- Residential developments of 1 to 9 dwellings on less than 1 hectare of land, or sites with less than 0.5 hectares and an unknown number of dwellings
- Commercial development with less than 1,000 square metres of floor space, or sites with areas that are less than 1 hectare.
You may not use the Small Sites Metric for projects that involve waste development, winning and working minerals, or the use of land for mineral-working deposits.
And even if you meet the above qualifications, you’ll also need to answer “yes” to the following questions to confirm that you should be using the SSM tool:
- Are all habitats on your site available for selection in the Small Sites Metric? (If you have other habitats that are not included in the Small Sites Metric, such as riparian zones, you will need to move to the Statutory Biodiversity Metric.)
- Can you confirm that none of the following are on your site?
- Priority habitats.
- Statutory protected sites or habitats.
- European protected species.
Benefits of the Small Sites Metric
The Small Sites Metric provides many of the same benefits as the Statutory Biodiversity Metric but makes the process more accessible for smaller projects. Developers can use the Small Sites Metric from project site selection through delivery of 10% BNG plans. Engaging with the Small Sites Metric earlier in the process makes it easier to design for biodiversity and produce ecological benefits.
The Small Sites Metric offers the following:
- Calculates the biodiversity of existing habitats as well as enhancement and creation scenarios.
- Compares biodiversity options for the site.
- Forecasts biodiversity units and percentage change.
- Gauges the biodiversity units that are possible from area habitats, hedgerows, or watercourses.
- Provides insights for planning decisions and design improvements.
- Reduces the costs and time associated with planning and implementing BNG on small sites by using a simplified metric.
With Biodiversity Net Gain Management System™ (BNGAI™), AiDash can help you streamline your BNG application, whether you qualify for the Small Sites Metric or will use the Statutory Biodiversity Metric calculation tool.
BNGAI™ helps you through 6 simple steps, from creating preliminary baseline assessment and BNG baseline report, to considering post-development scenarios and creating a BNG action plan, to producing submission-ready documents to get your application ready to file with your LPA.
Learn more about how BNGAI™ simplifies the BNG application process here.
Hannah Williams, Senior Ecologist
Hannah brings 14 years of ecological consultancy to AiDash, including 5 years experience specialising in biodiversity net gain. She has guided complex infrastructure and corporate strategic BNG projects in the UK and internationally.