Consultation outcome

Government response

Updated 9 December 2023

Introduction and context

The UK Government is committed to leaving the environment in a better state, delivering sustainable development and levelling up communities. This commitment includes addressing the conservation and sustainable use of marine resources, recognising the many uses of the marine environment.

The 25 Year Environment Plan and the Environmental Improvement Plan are driving the implementation of both biodiversity net gain (BNG) and marine net gain (MNG) in England, which is an approach to development that aims to leave the marine environment in a measurably better state than beforehand. They commit government to embedding environmental net gain (ENG), together with other duties, tools and strategies, to help put us on the path to nature’s recovery. The 25 Year Environment Plan pledges to ‘reverse the loss of marine biodiversity and, where practicable, restore it’ and the Environmental Improvement Plan confirms that we are developing MNG policy, exploring its potential to protect and restore habitats and species.

Net gain is an approach to development that aims to leave the natural environment in a measurably better state than beforehand. This means protecting, restoring, or creating environmental features that are of greater ecological value to wildlife, habitats and people than any losses associated with the new development.

In 2018, the UK Government consulted on making BNG mandatory for new development on land, and respondents suggested that net gain principles should be extended to marine developments. In its 2019 response, the UK Government noted that more work would be needed to define an approach to net gain that was appropriate for the marine environment.

In June 2022, Defra published its consultation on the principles of MNG which set out the aims for net gain policy for the marine environment and development within it. The main part of the consultation set out the proposed core principles of MNG and sought views on whether to mandate net gain for marine developments, the scope of MNG and how net gain could be applied.

We started to define the sorts of environmental improvements we expect MNG to deliver and proposed both strategic and site-based approaches to net gain, designed to be simple and clear for all stakeholders to use while delivering measurable gains for nature.

We sought views on taking a broader environmental net gain approach from the outset. This puts biodiversity at its core but also allows for the inclusion of wider environmental services where these would provide additional benefit.

We published a summary of responses on 21 March 2023. The high-level principles of MNG were generally supported by consultees who also provided a range of views on the detail of the policy which has informed this government response.

Government response - Part 1: defining marine net gain

Measuring impacts on habitats and species

We asked whether MNG should assess impacts on species as well as habitats to identify the residual impacts of a development. Stakeholders widely supported this as a way of achieving a whole ecosystem approach. Therefore, the government will include impacts on both habitats and species within the MNG assessment framework.

We recognise views from stakeholders about the complexity this could add to an assessment and the risk of ‘double counting’ impacts. However, as highlighted by respondents, due to the dynamic nature of the marine environment, we believe that habitats alone would not provide a comprehensive view of a development’s impacts. Stakeholders also wished to differentiate between temporary and permanent impacts. We will explore these views during the development of an assessment framework for MNG.

Respondents were also supportive of an MNG assessment framework considering the ‘off-site’ impacts of a development while recognising the potential challenge of implementing. The government will continue to develop an assessment framework that also considers impacts beyond site boundaries.

Incorporating environmental benefits in MNG

We asked whether MNG interventions should be assessed with reference to environmental benefits that biodiversity enhancement can yield. Stakeholders strongly supported this, and government agrees this remains consistent with the nature first approach. Therefore, the government intends to recognise wider environmental benefits when assessing MNG interventions.

As set out in the consultation, MNG will take a ‘nature first’ approach, with net gain for biodiversity remaining a core requirement. MNG will incorporate a wider environmental net gain approach but only where these extra benefits are underpinned by biodiversity enhancement. This is intended to support, for example, secondary considerations important for mitigating and adapting to climate change, such as carbon sequestration and storage and protection from flooding, which would provide the opportunity to restore blue carbon habitats and build resilience to climate change.

We asked which extra environmental benefits and services should be included within MNG assessments. Suggestions included underwater cultural heritage (UCH), climate change control practices and habitat benefits. The government will actively consider stakeholder suggestions, but only those which align with the ‘nature first’ approach. We will further investigate how best to account for environmental benefits through the future MNG assessment framework.

Positive incidental effects

We received mixed consultation responses for our proposal to discount potentially positive incidental effects, whose benefits are subject to significant uncertainty, from MNG assessments.

The majority of respondents supported the government’s proposal and highlighted important considerations to better define where there is ‘significant uncertainty’ and the need to keep this under review as more data becomes available.   

However, the government recognises that over 40% of respondents were against discounting positive incidental effects in MNG, with some suggesting that there is already sufficient evidence to support the inclusion of artificial reefs.

We will explore the role of positive incidental effects in developing the MNG assessment framework with due consideration of any significant uncertainty.

There was a range of feedback on the proposal to discount potentially positive incidental effects created by artificial reefs and other exclusionary effects, for example fisheries pressure reduction. Due to the mixed stakeholder feedback, the government will explore artificial reefs and other exclusionary effects further to strengthen our evidence base and consider their inclusion within the MNG assessment framework.

Contributions-based and metric-style approach

We proposed to prioritise a contributions-based assessment approach whilst still exploring the viability of a biodiversity metric-based approach. Most respondents supported this proposal, recognising that this would allow for MNG to be set up quickly whilst the metric is still being developed. However, several said they didn’t have sufficient information on what a contributions-based approach would look like to be supportive of our proposal. Many also considered that contributions-based approaches are unsuitable, particularly if they are not linked to the level of environmental impact. The level of monitoring required and the risk of delaying roll-out of the metric-based approach were also noted. Some respondents recognised that even an initial contributions-based approach needs to be accompanied by a robust assessment framework requiring consultation and engagement given the complexities of impact pathways and methods.  

The government intends to further explore a selection of options for a contributions-based approach alongside work to explore the applicability of biodiversity metrics to the marine environment. This will be supported by continued stakeholder input, to help define an appropriate MNG assessment framework. We welcome the engagement and ongoing input from the strategic net gain task and finish group funded by the Crown Estate offshore wind evidence and change programme, and other industry engagement (Renewables UK and Energy UK) on feasible mechanisms for delivering MNG. Alongside further stakeholder engagement on evaluation options with Natural England, this will help inform our understanding of potential design options for an approach that can progress MNG delivery.

We suggested that the marine recovery fund (MRF) could be used to manage financial contributions as part of a contributions-based approach to MNG. The MRF is a key component of the offshore wind environmental improvement package (OWEIP) within the British Energy Security Strategy announced in April 2022. OWEIP is a package of measures designed to support the accelerated deployment of offshore wind whilst continuing to meet our environmental commitments. 

At present the MRF’s proposed remit is to deliver strategic compensatory measures for the offshore wind industry alone. This is because of the significant amount of offshore wind developments that have triggered the need for compensation for marine protected areas (MPAs). MNG will apply to all developments in English waters and in the future, the government intends to consider whether it is appropriate for the MRF to deliver MNG. Further legislation would be needed to make this possible. We will continue to work with stakeholders in the next phase of MNG policy development to consider interactions with existing environmental assessment regimes, including possible complexities.

We recognise stakeholder views about the basis for contributions and that a contributions-based approach might not be linked to the level of impact. However, the government intends for MNG to operate alongside existing planning policy and practice, including on environmental assessments, to ensure current environmental standards are implemented and maintained, including application of the mitigation hierarchy. We will work with stakeholders to develop an appropriate process for evaluating MNG and a basis for contributions, which takes account of the level of impact.

We asked stakeholders whether there are other approaches to measuring impacts we should explore, and a wide variety of approaches were suggested including assessing heritage impacts and considering cumulative impacts of developments and external pressures. The government thanks stakeholders for their suggestions and will consider them further when developing a suitable assessment measure for MNG.

Part 2: Scope of marine net gain

Geographical scope of MNG

MNG will only apply to developments, or infrastructure forming part of developments, in English waters.

The Environment Act 2021 provides for net gain by way of amendments to the Town and Country Planning Act 1990 (TCPA) and the Planning Act 2008. Development on land and in intertidal locations, down to the mean low water mark, will therefore be required to deliver a mandatory biodiversity net gain (BNG). MNG will only apply to developments below the mean low water mark.

Some stakeholders suggested that the scope of MNG should be extended to include the intertidal zone. However, views were also expressed over the uncertainty that this would cause in how MNG and BNG operate alongside and complement one another without causing additional burdens. As the intertidal zone will be subject to BNG regulations, the government wishes to ensure that MNG is as coherent with BNG as possible by avoiding any overlap between the two regimes. We recognise that planning, consenting and licensing regimes, and their respective net gain regimes, may overlap in certain circumstances. The government intention remains that only one net gain regime will apply to each element of a development, so there is no duplication of net gain requirements. The government will provide clarity on how the various net gain regimes will interact as MNG is developed, in particular how MNG will work alongside BNG at the coast.

Making MNG mandatory

We asked whether MNG should be a mandatory requirement for new development activities within the marine environment. This is consistent with the terrestrial BNG approach. Respondents strongly supported our proposal. There were, however, calls from some for greater clarity on implementation to better inform their response. The government continues to intend to make MNG a mandatory requirement for all new in-scope development activities in English waters below the mean low water mark, recognising the benefits this will bring to the marine environment. This will be in addition to any statutory protections, such as compensatory measures requirements under the Habitats Regulations and The Marine and Coastal Access Act (MaCAA), without replacing them.

Other statutory measures will contribute towards reducing the residual impact of a development and then additional MNG measures will be required to achieve a net gain beyond no net loss. The intention is that MNG can address the shortfall to no net loss where needed and go beyond that to achieve a net gain. The government will do more to address uncertainty in the approach for implementation, recognising responses that asked for a net gain approach that is robust and clear in what is required. Further legislation will be needed to implement a mandatory approach. We will consult further before bringing forward the legislation and not proceed with a mandatory approach until we have completed a full impact assessment to understand the costs this would pose to marine developers.

Development scope of MNG and exclusions

We proposed that MNG should apply to economic activities that can be considered ‘development’, namely those that involve construction or installation of new infrastructure (including significant extensions or improvements to existing infrastructure) or extraction (such as aggregates).

We sought views on whether introducing MNG under the following regimes would achieve near total coverage of marine development activities and asked whether respondents agreed with this list or if there were other regimes we should consider:

• The Planning Act 2008
• The Marine and Coastal Access Act (MaCAA) 2009
• The Petroleum Act 1998

Stakeholders supported our proposal that MNG be applied to new development activities under these regimes. Several additional regimes were suggested by some stakeholders including the Energy Act 2016 and the Marine Works Regulations 2007. The government confirms that the three regimes we initially proposed are in scope and will also explore whether the additional regimes proposed by respondents would help to provide a consistent approach to define marine developments for the purposes of MNG.

A wide range of recommendations were made in the consultation for activities and sectors that should not be covered by MNG, as well as differing views on minimum thresholds for each proposed regime for MNG. Suggestions included the use of spatial thresholds, similar to the BNG approach, and the exclusion of all activities that are exempt or subject to self-service licences under MaCAA 2009. The government will further explore minimum thresholds for excluding development activities from MNG requirements. This is likely to include developments that would result in negligible loss or degradation of habitat. We also seek to align with existing regulatory approaches that provide thresholds and exemptions. We will provide clarity of the definition of ‘new development’ and minimum thresholds in due course.

Consultation proposals on the principles of MNG were set out to provide an approach for new developments in English waters. Many respondents told us that these developments do not exist in isolation and other types of uses and activities in the sea should be included to be equitable and avoid other sectors undermining what net gain policy is seeking to achieve. Whilst we recognise these views, MNG does not exist as a policy in isolation and is intended to be a tool for use in planning policy for development that sits alongside a suite of wider measures under the Environmental Improvement Plan to improve the marine environment. Expanding the scope to sectors that are not considered ‘new development’ under the regimes identified above could hinder the ability to define a clear and transparent approach to marine developments that is equivalent to the principles applied on land through BNG.  

We note that fisheries in particular were highlighted as an economic activity that some respondents thought should be included in the scope of MNG. However, there is already an existing framework to manage UK fisheries including the Fisheries Act 2020. This framework includes legal obligations to address the environmental effects of fish and aquaculture activities on the marine environment. The 8 objectives in the Fisheries Act include:

• the ‘sustainability objective’ for fish and aquaculture activities to be ‘environmentally sustainable in the long term’
• the ‘precautionary objective’ which requires that the precautionary approach is applied to fisheries management and that the exploitation of marine stocks restores and maintains populations of harvested species above biomass levels capable of producing maximum sustainable yield
• the ‘ecosystem objective’ that fish and aquaculture activities are managed using an ecosystem-based approach so as to ensure that their negative impacts on marine ecosystems are minimised and, where possible, reversed

The Joint Fisheries Statement (JFS) sets out the policies for achieving, or contributing to the achievement of, the fisheries objectives, and explains the use that the Fisheries Policy Authorities will make of fisheries management plans (FMPs) in achieving those objectives.

The government will therefore not include fisheries within the scope of MNG requirements. We will work to provide transparency on how MNG fits across a range of wider policies and measures that seek to deliver shared goals.

Part 3: Defining interventions

Pressure reduction in MNG

Respondents suggested a wide range of pressure reduction measures for use in MNG. The government believes that these, alongside active interventions, can be an effective means of addressing biodiversity loss, whilst also providing wider environmental benefits. Therefore, MNG will comprise both active interventions and appropriate pressure reduction measures, taking into account those suggested by respondents. Proven restoration or protection techniques will be encouraged in the first instance, but MNG will also support the deployment of novel types of interventions and pressure reduction measures where these can offer opportunities for ecosystem recovery.

Some respondents were of the view that pressure reduction could be inconsistent with the polluter pays principle and may be difficult to deliver without support from the government. Whilst the government believes that pressure reduction measures can be a meaningful tool in achieving recovery of the marine environment, it will consider these views fully and further detail on appropriate pressure reduction measures will be provided in the consultation on the implementation of MNG.

Whilst the government does not consider fisheries to be an in-scope activity for MNG, it recognises the fisheries sector can contribute to delivery of pressure removal and reduction measures suggested by stakeholders. Where a strategic benefit can be demonstrated, the government will consider the delivery of net gain interventions by industry that involve fisheries pressure reduction measures.

Part 4: Taking a strategic approach

Taking both a site-level and a strategic approach

We asked stakeholders if they agreed with the principle of taking both a site-level and a strategic approach to MNG. We proposed that developers will have the flexibility to propose meaningful site-based interventions or strategic interventions due to the differing suitability of these for specific developments. There was significant support for our proposals, recognising the flexibility this provides and the opportunity to maximise environmental benefit. Therefore, the government will consider both site-level and strategic interventions in MNG.

The government recognises some stakeholders’ concerns about decoupling the development location from the intervention and the subsequent impacts this could have on ecological networks, local communities and stakeholders. As highlighted in the consultation, this approach is intended to deliver maximum environmental returns, allowing flexibility when site-based interventions may not be feasible or environmentally desirable relative to other strategic options. As we move towards implementation of MNG, the government will carefully consider stakeholder views when developing an appropriate assessment framework for impacts and interventions.  

Types of site-based and strategic interventions

Respondents suggested a range of site-based and strategic interventions, including both proven and novel measures. The government will appraise these interventions and intends to publish guidance on appropriate interventions for MNG before it becomes mandatory.

Some respondents supported our proposal that interventions should be delivered or designed in collaboration with stakeholders, for example environmental groups and local communities. The government intends to continue engaging with these groups and wider stakeholders while preparing guidance for site-based and strategic interventions. For example, the strategic net gain task and finish group, made up of stakeholders, has been investigating potential strategic interventions for MNG. Their recommendations, alongside evidence from government-led initiatives, such as the Environment Agency’s restoring meadow, marsh and reef (ReMeMaRe) project and other evidence, will be used to support MNG policy development. The government values the engagement we’ve received from stakeholders and their continued support for our development of an evidence base for MNG delivery.

Incentivising appropriate site-based interventions

The government’s position is that the intervention that delivers the greater environmental benefit should be selected, taking into account whether interventions are technically and economically feasible. We intend to develop an approach to delivery that ensures flexibility, supports innovation, and ensures the greatest benefit to the environment can be achieved. We asked which site-based features should be considered priorities ahead of strategic priorities.

Responses included rare or threatened features and features of conservation importance. Reference was also made to the ‘irreplaceable habitats’, mirroring the BNG approach, however further work is required on the evidence and policy of irreplaceable habitats which are less well defined in marine planning policy. The government intends to embed the principles that both a site-level and strategic approach can be achieved. It will consider where guidance is needed to support the selection of site-based interventions where they can better address residual losses of features that are particularly rare or sensitive. This approach will keep MNG in line with the mitigation hierarchy and ensure interventions are selected principally based on environmental benefit rather than cost or convenience.

Spatial relationship of developments and interventions

The government’s position, supported by the majority of consultation responses, is that MNG interventions should not initially be restricted to the locality of the main development. Respondents recognised the wider benefits strategic interventions can provide. Therefore, the government will not, initially, introduce a requirement for interventions to be sited in the locality of the main development.

We recognise respondents’ concerns around decoupling the location of the development and the intervention. As stated in the consultation, the longer-term aspiration is to localise the benefits of MNG to the impacts where appropriate. Whilst local interventions will not be incentivised at first, the government will continue to consider wider regional and strategic spatial scales to support the delivery of MNG.

Part 5: Marine net gain and additionality in Marine Protected Areas

Enhancement of designated features within statutory MPAs

In response to the strong support from the consultation, the government intends to allow for improvements to features of MPAs to qualify as net gain interventions. We recognise that, due to the large percentage of marine habitats that are designated MPAs, their exclusion from MNG would make it more difficult to identify locations to deliver MNG and could constrain investment in enhancements in coastal and marine environments.

This follows the proposed approach for BNG to allow for improvement to features of MPAs in the intertidal zone. This will support the alignment of BNG and MNG policies at the mean low water mark.

Several respondents flagged concerns about this approach, suggesting that it could lead to MNG replacing the government’s existing obligation to ensure the effective management of MPAs that should occur independently of any development. This is not the intention. Measures required to fulfil an existing statutory obligation for the management of MPAs will not count towards MNG. However, if they deliver an additional enhancement in line with MNG principles beyond meeting the existing obligation, that enhancement will count towards MNG.   

Subject to further consultation on the implementation of MNG, the government will ensure that interpretation of the additionality principle in the context of MNG is accompanied by additional safeguards to ensure the integrity of the MPA network. Additional questions were raised around how the enhancement of MPAs fits with wider MNG objectives. MNG is intended to secure lasting positive outcomes for the wider marine environment and is not focused on particular MPA targets.

Relationship between MNG and Compensatory Measures

Several respondents requested clarity on how MNG and compensatory measures will overlap and interact. The compensatory measures requirements under the Habitats Regulations and MaCAA are distinct from MNG requirements. MNG is intended to be a new requirement for developers. It will not replace or supersede existing requirements relating to compensatory measures. It will secure measures to reach no net loss where needed and go beyond that to achieve a net gain. 

The government recognises several key differences between the two policy areas:

• MNG is wider in scope than the remit of MPA compensatory measures as it aims to enhance the wider marine environment beyond simply achieving no net loss for a development
• compensatory measures aim to ensure that the overall coherence of the national site network is protected and/or to secure measures of equivalent environmental benefit to the damage the development will or is likely to cause, up to no net loss
• MNG will apply to England only whereas MPA compensatory measures apply across the whole of the UK

We recognise that there will be developments seeking to achieve both compensation and MNG objectives. The measures required to comply with compensation requirements will contribute towards reducing the residual impact of a development and then additional MNG measures will be required to achieve a net gain beyond no net loss, as they are for BNG.

Further work is required on the MNG assessment framework to define how this can be established, as well as close working with approaches to strategic compensation for offshore wind development. The government will work with stakeholders to clarify further the distinction between the policy areas as delivery mechanisms are established.

Part 6: Next steps

This consultation has confirmed strong support from a wide range of stakeholders for the principles of MNG and for the government to continue developing the detail of the policy. We welcome this engagement and will now commission the evidence needed to take these proposals forwards. This will be shaped by the views of stakeholders who will be invited to contribute to policy development.

Key actions in the next phase of policy development are:

• develop an assessment framework for MNG delivery, further considering the options of a contributions-based approach and a suitable simple metric to assess impacts and interventions in the marine environment
• create and run proof of concept projects for the assessment framework
• develop detailed policy on the implementation and delivery of MNG as part of planning decisions
• carry out a full impact assessment of the benefits and cost of implementing MNG
• seek appropriate legislative powers, as needed, to introduce MNG requirements

After we have developed the policy in conjunction with stakeholders, we will hold a further consultation with stakeholders prior to any implementation.

Glossary

BNG: Biodiversity net gain

ENG: Environmental net gain, improving all aspects of environmental quality through a scheme or project. Achieving environmental net gain means achieving biodiversity net gain first, and going further to achieve net increases in the capacity of affected natural capital to deliver ecosystem services

eNGO: Environmental non-government organisation

EUK: Energy UK

MaCAA: Marine and Coastal access Act 2009

MNG: Marine net gain

MPA: Marine protected area

NSIP: Nationally significant infrastructure projects

OWEIP: Government’s Offshore Wind Environmental Improvement Package in the British Energy Security Strategy

OWES: Defra’s offshore wind environmental standards project

ReMeMaRe: Environment Agency’s restoring meadow, marsh and reef project

RUK: Renewables UK

UCH: Underwater cultural heritage