Biodiversity Net Gain (BNG) was made mandatory in almost all planning applications from the 2nd of April 2024. This basically means that development must show an increase in quality habitats by at least 10% from what was there before development.
Who does it effect? It affects anybody wishing to put in for planning (bar a few exceptions that we will come on to). This means that landowners, farmers, developers, householders, planners and so on will need to now take this into account when considering planning projects. The Biodiversity Net Gain information is required in the first step of submitting a planning application, and therefore an application cannot move forward without it.
BNG is split into two categories. This is known as the ‘Small Sites Threshold’ and the ‘Standard Metric’.
Small sites include small scale residential development (I.e., up to 9 dwellings). For other development - like commercial and agricultural - the floor space created must be under 1,000m2 or total site area being less than 1ha to be a ‘small site.’ Further guidance and thresholds for other types of applications is provided in the links at the end.
So, unless the application forms part of an exemption, any other applications not under the Small Sites values will be accountable to the ‘Standard Metric’. Standard Metrics require a greater -in depth analysis of BNG compared to Small Sites and this was made mandatory back in February.
A lot of rural projects do, therefore, fall under this Small Sites Metric threshold and hopefully we can help ‘make sense’ of what this means for you and your planning proposals….
Firstly, your planning application must show at least a 10% biodiversity net gain. This comes in the form of a ‘gain plan’. This plan shows the habitats (it can be either ‘on-site’ or ‘off-site’) that have been secured for over 30 years. The habitat creation is relative to the size and complexity of the development. Ecologists use a tool called ‘the metric’ to calculate what level habitat of habitat creation needs to be undertaken to show the all-important 10% biodiversity net gain.
What is the cost implication?
Secondly, budgeting for your planning application. There are now more requirements to be included in the first steps of a planning application. The BNG means further site assessments and reports need to be completed. These additional requirements have to be done by a qualified ecological consultant.
For small sites the ecologists will calculate a ‘baseline’ value of ecological condition of the site, complete a metric calculation and draw up site plans which show any irreplaceable habitat in relation to the site. This information will have to be submitted alongside planning statements, application forms, standard drawings and any other initial planning documents.
So, how do you budget for the new requirements? Well, whilst each project will have individual quotes for BNG – it is safe to say that the new legislation will increase initial costs, and potentially lengthen time frames for submitting an application.
Ecologists have suggested that BNG assessment approximately doubles the time required on site. We are hoping with time and experience of this new legislation, we can provide further guidance to yourselves as the applicants as to the timescales and specific budgeting created by this Biodiversity Net Gain requirement.
Rough guidance on ecologist costs for a completed BNG assessment stands at around £300. This is relative to when the standard ecological assessment known as a PEA for a site would usually be about £450 (pre-BNG additional requirements), therefore taking the total ecological survey cost to £750.
A ‘Standard Metric’ and therefore anything ‘bigger’ than the small sites, alongside a completed ecological assessment would be ballparked around £2,500. These figures are approximate values and are adjusted significantly depending on various aspects of the planning proposal.
Where can I find out more information?
Please find below links here to government guidance pages, the list of exemptions from BNG and interesting articles relating to agricultural and rural planning implications.
Biodiversity Net Gain FAQs - Local Government Association
Biodiversity Net Gain: Exempt Developments - Gov.UK