Biodiversity Net Gain Summer 2021 events

PAS ran three workshops for local authority planners, one for London Borough officers and one for councillors in May, June & July 2021. The workshops were pitched as providing an introduction to what is happening with the Environment Bill and Biodiversity Net Gain and a chance for attendees to let PAS know what they want and need from our Net Gain Capacity and Skills project. This page provides a summary of outputs from the workshops, including what local authorities are doing now on biodiversity net gain (BNG) and what they need to enable them to be ready for mandatory BNG.


PAS ran three workshops for local authority planners, one for London Borough officers and one for councillors on 25th, 27th May and 9th June, 16th July and 16th June respectively. The workshops provided an introduction to what is happening with the Environment Bill and Biodiversity Net Gain and a chance for attendees to let PAS know what they want and need from our LPA Biodiversity Net Gain Capacity and Skills project. With the exception of the London Borough event, we specifically aimed them at those without ecological expertise. 

Presentations from the events are available on our Biodiversity Net Gain front page.

Image of words from poll asking LPAs 'in one word, how do you feel about biodiversity net gain?'

Word cloud from poll of attendees of 25 May 2021 event for planners 

Who came along?

Map of England with dark blue shading showing which local authorities attended PAS Biodiversity Net Gain workshops in Summer 2021

Map of BNG workshop attendees by local authority (county council attendees not mapped)

We had representation from 178 different local authorities for the open events pitched at all local authorities, with 230 attendees signed up to the planners’ workshops and 77 councillors attending their event. Sixty-seven officers from 26 London Boroughs signed up for the event targeted at them.

Attendees of the planners’ workshops included both policy and development management planners, as well as heads of planning, ecologists and biodiversity officers, as well as a range of other council roles. We had 223 attendees in planning roles and, of those that provided this information, a significant majority were policy planners rather than development management. Eighteen of those that signed up to the overarching events were ecologists, biodiversity officers or equivalents, whilst we had 15 in these roles and including Environment Managers or equivalent for the London Borough event. 63% of attendees of the overarching planners’ events had worked with or been to a PAS event before.

We did not ask all councillor attendees what their role was but 26 of them answered a pre-workshop call for information and there was a range of roles represented from Portfolio Holders and Cabinet Members for the Environment, Planning Committee Chairs and Members, to Ward Councillors. Just under half of attendees had worked with or been to a PAS event before.

How do local authorities feel about biodiversity net gain?

We undertook in-event polls to get a broad understanding of how attendees felt about delivering biodiversity net gain.

We asked planners whether their Authority is currently involved in the delivery of any BNG in their authority area, given that Biodiversity Net Gain is currently encouraged in national planning policy, and 50% were and 50% were not. Councillors were not always aware of what was happening in their area, 51% of attendees said that their Authority is currently involved in BNG delivery, 26% that it was not and 23% did not know. This was mirrored in London Boroughs where 34% of attendees said that their authority area is currently involved in BNG delivery, 28% that it was not and 38% did not know.

We asked planner attendees which of the following aspects of BNG they felt most able to deliver in their authority:

Aspect of Biodiversity Net Gain

Percentage of LPA officer attendees that felt able to deliver this in their authority area

Percentage of London Borough event attendees that felt able to deliver this in their authority area




Development management



Offsite delivery



Link to place making and wider authority interests



Members' interest/understanding



Third sector engagement



None of the above




The majority (67%) of councillors were very or somewhat confident their local authority can be ready to deliver the requirements of the Environment Bill by Autumn 2023, but 20% did not feel at all confident or did not know. Three quarters of councillor attendees said they understand what their role as a councillor is in helping their authority deliver biodiversity net gain and other requirements of the Environment Bill.

There is a significant variation in what LPAs are already doing in terms of net gain, expressed in the discussions during break-outs in the planners’ workshops and post-event feedback. When asked where they felt they were on a scale of 1-10 in terms of what they are doing now, the majority of attendees put themselves at 5 or below.

What are local authorities doing now?

Planning Policy

Whilst a majority of those attending the workshops either had a policy in place or one in preparation in their Local Plans, there was a range in the type of policies in place from no net loss through those encouraging enhancement and net gain to those with a specific target and metric, and some had SPDs adopted or in preparation. For example, Rochdale has a no net loss policy, Hull City has a policy for BNG ‘commensurate to size of development’, Oxford City a policy for 5% BNG and Mansfield a policy for 10%. Often the type of policy depends on how recently the Local Plan had been adopted - Rochdale’s plan was adopted in 2016 and Hull’s 2017, whilst a number of LPAs at Regulation 19 stage for their Local Plans were planning a 20% target in their BNG policies.

Development Management

Amongst LPAs with a policy in place or about to be adopted, there were concerns about its implementation through to development management decision-making, i.e. having a net gain policy in place did not mean it was actually being delivered. However, a significant number of LPAs provided examples of net gain achieved through development decision-making. In some cases, these are in specific circumstances or where the opportunity arises only, for example Winchester and West Suffolk both encourage net gain for developers of large sites and Rushcliffe ‘where possible’. County councils, such as Surrey, highlighted their experience of delivering net gain through minerals development, as well as through their own capital projects (West Sussex).

There are also LPAs delivering net gain on a more ad-hoc or opportunistic basis in advance of policy being in place, for example in Swale Borough, where they are asking for 20% net gain in advance of their Local Plan being adopted and have examples of planning permissions securing net gain via condition, and the London Borough of Bromley, where they have used the London Plan policy G6 to deliver net gain on a number of developments.

Offsite delivery

There was generally less experience of delivery of offsite BNG, but a few examples were cited, such as Coventry who use the Warwickshire net gain calculator and take developer contributions for offsite delivery, and Doncaster, who have just agreed their first habitat bank site to allow the sale of units to developers. A number of local authorities were looking to work with others at a county/city-region level, such as High Peak BC, who are currently trying to work with partners and other Derbyshire LPAs to look at county-wide offset.

What do local authorities want support on?

As a general principle, LPAs want consistent messaging and best practice, formally endorsed by MHCLG / DEFRA so that they have a recognised ‘go to’ place for guidance/advice.

We have compiled the outputs from the workshops into seven themes setting out the support that LPAs want and need to be ‘day one ready’ for mandatory BNG:


A coherent local strategy for BNG - How does it all join up?

Many officers who participated in the workshops are responsible for developing local planning policy or local plan making. As such, it is perhaps not too surprising that participants are keen to understand how new responsibilities and legal requirements around BNG should be interpreted and focused to the best effect for the local environment.

Whilst a lot of planners are familiar with Local Nature Recovery Strategies (LNRS), little is known about these, e.g. the status of a LNRS, who is responsible for developing them and how they will operate or help to deliver BNG. In particularly, the need to ensure that opportunities for off-site net gain (or habitat banks) are available, and ensure that these are secured for 30 years, is seen as a major challenge for LPAs.


Local Plan making - What does all this mean for our local plan?

Linked to theme 1 and the wider strategy needed to implement BNG effectively in an area, many workshop participants asked detailed questions on the implications of mandatory BNG for their local plan. A large number of these questions relate to evidence and how BNG policies will need to be evidenced, but other participants were keen to discuss the potential for Local Plans to develop a distinctly local approach to BNG, i.e. moving beyond the essentials set out in new legislation and the NPPF to address specific needs in different areas or local environments.

Of course, many LPAs already have BNG policies in their plan and are seeking to implement this through DM decisions, but even in these areas new legislation may require changes.


Effective implementation through development - How do we stop developers from gaming the system?

Feedback from local planners and Councillors suggests there is some scepticism (or at least the need for reassurance) on the likely success of mandatory BNG. Issues are largely around the extent to which developers will work within the spirit (as well as the detailed legal requirements) of BNG, with the results that a significant burden will be placed on LPAs to ensure that BNG is delivered. The suspicion, that developers could “game the system”, was particularly strong amongst elected members who were keen to find out how their authority could make sure developers “follow the rules”.

More widely though, participants want to ensure they have the tools and resources available to ensure real improvements are delivered, meaning there is a need for additional evidence, closer scrutiny of applications and the use of the BNG metric, legal (S106) agreements, additional monitoring, enforcement, etc.


New legislation and a nationally designed system – How do we check we are following the rules when making decisions?

In the workshops, we summarised the work currently underway by Natural England and Defra, including a range of new tools, regulations or processes that are being established to support mandatory BNG, such as the national site register, biodiversity metric 3, small sites metric, national BNG credits system, etc.

Understandably, many planners and elected members are currently struggling to understand some of these and the implications for their LPA, even in areas where BNG is already being implemented. Some of the questions raised could be answered immediately and relatively quickly, whilst others are genuinely unknown, and answers still need to be confirmed or worked through. It is clear that we will have to get more comfortable with continuing to work with some uncertainties or unknowns for the next two years.


Viability – What impact will BNG have on viability in my area and how do we respond?

Issues with viability were raised at all of the workshops, i.e. concerns around the impact that BNG will have on the viability of new schemes (especially housing) or the wider whole plan viability in some cases. Accepting that BNG will be supported by legislation, many planners are thinking ahead to how they evidence the viability impacts for a Local Plan or how DM officers will factor in BNG as part of the wider planning balance that is struck between other needs, such as affordable housing, road infrastructure, recreation, etc. particularly if a CIL is already in place.


Stacking or additionality - How do we join this up with wider environmental planning?

Stacking is a relatively new term for planners and refers to the way that the requirements of BNG can be delivered alongside other environmental goals.

For many planners and Councillors, mandatory BNG is very much a welcome initiative from the Government, as it is seen as bringing positive outcomes for an area, but there is a concern to ensure that BNG is not pursued in isolation, and that other policy goals such a flood risk mitigation, Green Infrastructure, active travel, etc can be delivered at the same time and on the same sites as BNG without conflicts. There is also a concern around how offsite BNG fits with other environmental mitigation involving habitat enhancement and creation, such as Natura 2000 site mitigation (like SANGs and nutrient neutrality) and great crested newt district level licensing.


Capacity and capability - Who is going to do all this new work and do we have access to the skills we need?

Finally, common to every session held with planners and elected members was the issue of LPA capacity and capability. BNG is a new concept for some LPAs, and even where BNG is already required in a Local Plan the requirements of mandatory BNG is new. As such, many planners are struggling to find the time and space required to understand and prepare for BNG, as well as identifying additional requirements for some skills that may be in short supply (such as ecology) and need to work with new stakeholders (such as local wildlife trusts) to deliver net gain.

This concern about “extra work” for planning teams is aggravated by the level of uncertainty created by the Government’s planning reforms. Questions on the availability of skills and capacity in the short term are closely linked to wider questions on the shape of the planning system in the long term.


Running across all of these themes, and evident from our discussions at the workshops, is an over-arching focus from LPAs on delivery and implementation, i.e. a desire to ensure that the new arrangements being established for BNG deliver tangible benefits for an area; and are able to do this as quickly as practicable and certainly before the “day  one” requirement for mandatory BNG comes into place. Topics related to implementation were also raised in workshops, such as working with external stakeholders, organisational arrangements, capacity and links to other areas of environmental policy.

How do local authorities want to get support?

We asked attendees how they would most like to get support through the project. Online training events were the top answer in both cases, with detailed guidance and reading notes high on the list. Whilst these polls highlight majority preferences for particular support mechanisms, attendees were in favour of all the suggested mechanisms, indicating that a mixed offer is most appropriate. We also have more detailed input on how LPAs want to get support from the discussion sessions that we have factored into our base offers.

Next steps: our base offer

We have used these workshop outputs to develop a base offer for all local authorities with a focus on four elements:

  1. Over-arching principles: a planner-focused introduction to BNG and how this complements/fits into core planning work, plus a narrative that goes beyond planning to link to wider local authority objectives, aimed at ‘heads of’, Councillors and others.
  2. Policy: aimed at policy planners and Councillors, guidance and tools to ensure to ensure that BNG is integrated into planning policy and Local Plans, that policy is supported by evidence, etc.
  3. Development management: aimed at development management planners and Councillors, guidance and tools to ensure effective decision making for BNG, supporting sound and defendable decisions, etc.
  4. Implementation: practically focused guidance on resourcing BNG, as well as events to support forthcoming Defra consultations on biodiversity net gain.

We will develop products with the project officer and councillor advisory groups. Please contact Beccy Moberly at PAS if you are from a local authority and interested in joining one of these groups.