The Environment Act 2021- the key implications for planning

Legislation Update
Print Page

The Environment Bill has recently received Royal Assent in the House of Lords and was passed into law on 9th November 2021 after a lengthy process; the Environment Act 2021 now represents the UK’s own domestic environmental law post Brexit and is a timely addition to legislation, in view of the recent COP26 Climate Summit. The Act has been championed as a world-leading and ambitious example of environmental legislation that puts the environment at the centre of development with tangible targets, plans and policies tailored to enhance the natural environment.


Biodiversity Net Gain

A key component of the Act, contained in Part 6, is the requirement for Biodiversity Net Gain (BNG): an obligation for developers to ensure all new proposals feature at least a 10% improvement to biodiversity; grants of planning permission are to be accompanied by a condition stipulating biodiversity gain which is to be managed for at least 30 years. This pre-requisite has been inserted into Schedule 7A to the Town and Country Planning Act 1990 or Schedule 2A to the Planning Act 2008 and is a significant step-change, moving away from the requirement to simply mitigate the impact of a development.

To monitor this, a “biodiversity gain site register” will be created for individual development sites which are also to be maintained for at least 3 decades following the completion of the scheme. BNG requirements will therefore have to be transitioned into local planning policy and development management.

Schedule 14 of the Act sets out that:

“The biodiversity gain objective is met in relation to development for which planning permission is granted if the biodiversity value attributable to the development exceeds the pre-development biodiversity value of the onsite habitat by at least the relevant percentage”.


The 10% biodiversity value attributable to the development is the total of:

(a)the post-development biodiversity value of the onsite habitat,

(b)the biodiversity value, in relation to the development, of any registered offsite biodiversity gain allocated to the development, and

(c)the biodiversity value of any biodiversity credits purchased for the development.

The legislation goes on to state that:

“In relation to any development for which planning permission is granted, the pre-development biodiversity value of the onsite habitat is the biodiversity value of the onsite habitat on the relevant date”.

Accordingly, developers will soon have to incorporate a Biodiversity Gain Plan in conjunction with planning application submissions, with legislation stipulating that the development may not be begun until the biodiversity gain plan has been submitted and the LPA has subsequently approved the plan.

The Biodiversity Gain Plan is to include:

– Details of the steps taken or to be taken to reduce the adverse effect of the development on biodiversity of the onsite habitat and any other habitat.

– The pre and post biodiversity value of the onsite habitat(post –development value must be at least the value specified in the plan.

– Any registered offsite biodiversity gain allocated to the development and the biodiversity value of that gain in relation to the development.

– Any biodiversity credits purchased for the development.

Of note, there is a mitigation hierarchy in respect of BNG as follows:

– Avoidance (such as intentional spatial placement of infrastructure and timing of construction). This approach is oftentimes the simplest and most cost-effective, however it requires biodiversity to be accounted for in the preliminary stages.

– Mitigation (measures to minimise the extent of impacts which cannot be wholly avoided).

– On-site Compensation (measures to enhance degraded or diminished ecosystems after exposure to unavoidable impacts. Varying levels of on-site rehabilitation/restoration can be adopted). On-site BNG commitments are likely to be included in a S106 or Conservation Covenant.

– Offset biodiversity losses off-site (As a last resort if compensating on-site is not possible or is not the most beneficial then facilitating gains off-site may be deemed sufficient).

This hierarchy therefore means that developers cannot simply go straight to the ‘pay off-site’ option; indeed, if it is possible to incorporate some BNG on-site this will need to be registered along with its management for the next 30 years, as set out within the corresponding Biodiversity Gain Plan. This is rather a substantial commitment, especially considering that BNG also applies to Nationally Significant Infrastructure Projects owing to a late revision to the Bill. In this respect, practical implications of any on-site BNG will need to be carefully considered.

It is understood that the latest Biodiversity Metric 3.0 is to be utilised to calculate net gain requirements. This metric enables all stakeholders to assess changes in biodiversity value facilitated by development or alterations in land management.

A developer may purchase a credit from the Secretary of State in lieu of this requirement, whereby an arrangement is made in terms of a fee paid in order to meet the biodiversity gain objective (albeit the cost of off-site credits is not yet known).

However, importantly, as previously indicated by DEFRA, there will be a 2 year transitional period before BNG becomes mandatory. This transitionary period is crucial in enabling the industry to prepare, nevertheless, it does not mean that developers can ignore these amendments for this interim period; BNG is already stipulated within the revised National Planning Policy Framework (NPPF) and in some Local Plans, thus revealing the extent to which certain authorities are already pushing this agenda. Now that the Environment Act is in place, it is likely that more Councils will follow suit with and require BNG.  BNG is likely to have notable implications for any development proposal, so should be considered at an early stage.  For example, any on-site BNG provision will have design and management implications whereas there will be financial costs associated with any off-site provision which may need to feed into the viability of a scheme.   BNG is also likely to impact on the validation process with additional supporting information required upfront.

From a Local Planning Authority’s perspective, the public authority must duly consider what actions they could take from time to time to “further the general biodiversity objective”. The authority must then implement policies and specific objectives to achieve this aim. These actions (such as conserving, restoring or enhancing the population of a certain species or protecting a particular habitat) must be undertaken within one year commencing from when the legislation came into force. Local Authorities must also publish biodiversity reports covering no more than 3 years and stating what the council has done to comply with these duties. The LPA can, however, revise policies and objectives and take action to further general biodiversity objective at any time.

The Secretary of State is to issue guidance on how Local Planning Authorities are to comply with this duty; however it is envisaged that the legislation will no doubt mean LPAs now have to engage with Natural England to a greater degree.


Additional measures

As advised in our earlier post on the Environment Bill, the Act also includes the mechanism of Local Nature Recovery Strategies: a network of spatial nature strategies which it is intended will encompass the entire country in due time.

Other tools include Conservation Covenants which are set out within Part 7 of the Act. Conservation Covenant Agreements is a local land charge and are agreements between a landowner and a responsible body. The conservation purpose is:

“(a)to conserve the natural environment of land or the natural resources of land,

(b)to conserve land as a place of archaeological, architectural, artistic, cultural or historic interest, or

(c)to conserve the setting of land with a natural environment or natural resources or which is a place of archaeological, architectural, artistic, cultural or historic interest”.

The legislation also establishes the Office for Environmental Protection (OEP) which has a wide remit including monitoring and reporting on the implementation of the environmental legislation, environmental improvement plans and targets.

This piece of legislation is certainly extremely significant given the high profile of environmental awareness both within the public domain and within all levels of government. The success of this landmark Act will become apparent over the course of the next few years as further guidance is published ahead of the formal introduction of BNG. The Government is to consult on BNG statutory instruments and regulations which will be a key step in preparing to implement these comprehensive requirements.

Firstplan will of course continue to monitor the evolution of this Act alongside future consultations and government guidance.


Article by Claire Stafford


The full Environment Act legislation is available at:
The Government’s Press Release is available here: