Biodiversity Net Gain – Liverpool City Region Combined Authority

Complying with Mandatory BNG

The Environment Act was introduced into UK law in 2021 and marked a turning point in how the natural environment is integrated into development planning. A key feature of the Act is the concept of biodiversity net gain (BNG), requiring developers to leave the environment in a measurably better state than they found it. Under BNG, developers must ensure that a development site’s biodiversity value is increased by at least 10% once all construction works are completed, leading to various considerations around habitat and land management requirements.

Once it had become mandatory following a two-year transition period, BNG turned into a legal requirement for planning applications in February 2024, except for a few specific exemptions. Covering all of Merseyside and Halton, Liverpool City Region Combined Authority (LCRCA) has been proactive in encouraging the adoption of BNG measures, prioritising the recovery and enhancement of its unique urban, coastal and green spaces. While the policy poses challenges for developers, it also opens opportunities to restore and improve the area’s natural environment.

Boosting the State of the Environment Across the Liverpool City Region

Liverpool City Region Combined Authority contains an accumulation of multiple local planning authorities, including Halton Borough Council, Knowsley Council, Liverpool City Council, Sefton Council, St Helens Borough Council and Wirral Council. It recently outlined its commitment to biodiversity through a variety of initiatives, such as its Local Nature Recovery Strategy (LNRS) and the development of ecological corridors connecting its six boroughs.

Such strategies aim to strengthen wildlife habitats and promote biodiversity across key ecosystems, including the Mersey Estuary, the wetlands of Halton and grasslands in the Wirral. Supplementary planning documents issued by LCRCA explicitly detail how biodiversity net gain will be embedded into local planning processes. Key priorities include enhancing biodiversity in urban areas like Liverpool and Knowsley, restoring degraded habitats in the boroughs of Sefton and St. Helens, and supporting the creation of new habitats in Biodiversity Opportunity Areas (BOAs).

The Combined Authority works in collaboration with national and regional partners – such as the Mersey Forest Partnership and the Natural Capital Working Group – to ensure that all efforts align with broader ecological and sustainability goals. As for specifically implementing biodiversity net gain in minor developments and major developments that apply, a BNG plan will be a mandatory requirement to improve the local environment and minimise biodiversity loss in the site area.

BNG’s Connection with the Natural World and Planning

Since the BNG process was better detailed for most development sites in February 2024 and small sites in April 2024, biodiversity net gain has represented a significant shift in how development projects are planned and executed. By making biodiversity a central part of the process, developers are required to demonstrate a tangible improvement in the ecological value of their sites. In the Merseyside region, the policy is particularly important due to the area’s combination of urban density, sensitive coastal zones and designated greenbelt areas.

Developers must undertake comprehensive ecological assessments using DEFRA’s biodiversity metric to calculate baseline biodiversity levels. In places like the Mersey Estuary which hosts internationally significant bird populations or the heathlands of St. Helens, developers need to consider the specific ecological value of these sites. The metric ensures accurate quantification of losses and required gains, enabling developers to formulate plans that meet or exceed the 10% improvement threshold.

The metric calculation will indicate biodiversity value on a pre-development and post-development basis, pointing towards what’s needed to satisfy the national policy. If achieving BNG on-site isn’t feasible, developers may need to explore off-site compensation through buying biodiversity units from a BNG market or biodiversity credits from government-approved sellers, contributing to larger-scale habitat creation projects elsewhere in the city region. Such initiatives include wetland restoration projects or expanding woodland areas within the Mersey Forest.

Surveys and Plans to Support Planning Applications

To comply with biodiversity net gain requirements, developers in the Liverpool City Region must first arrange for a thorough ecological survey of their site. The process identifies existing biodiversity features such as protected species, priority habitats and areas of ecological importance. Whether it’s urban wildlife corridors in Liverpool or peatland restoration projects in Sefton, understanding the ecological baseline as part of a biodiversity net gain plan is the first step.

Ecologists use the data gathered during the site survey to calculate the current biodiversity value and compare it to the projected biodiversity levels post-development. Using the mitigation hierarchy, the further information retrieved from the site allows for tailored recommendations on habitat improvements, species protection measures, and other steps necessary to meet BNG targets. For example, the ecologist may suggest the creation of new proposed habitats.

A last resort option allows for the competent person in charge of the assessment to suggest buying off-site units or credits. The BNG assessment is also vital for navigating planning processes, as the corresponding local councils will demand an evidence-based biodiversity gain plan before granting planning permission. Ecologists provide detailed reports outlining the actions needed to achieve compliance, ensuring that development projects can proceed smoothly while contributing to local biodiversity enhancement.

Book a Biodiversity Net Gain Assessment Now

At Arbtech, our expert ecologists understand the nuances of biodiversity net gain and the specific challenges faced by developers in the Liverpool City Region, not from only habitats present but also from local planning authorities and local communities. With extensive experience across urban and rural settings, we are equipped to provide the support you need to meet BNG requirements and navigate local planning systems.

You may need help with residential developments, planning projects where the small sites metric would apply or simply other guidance to confirm that house extensions or different types of new developments don’t fall within the biodiversity net gain mandate. Whatever the case, our team can provide evidence that accomplishing a 10% net gain increase is possible, benefitting your application for planning consent and potentially even assisting your landscape design.

To begin the process, contact us via phone, email or our quick quote form. The more detail you provide about your site and project, the better we can tailor our services to your needs. Once we’ve given you a no-obligation quote, we can arrange a site visit to assess your development’s biodiversity potential. As long as you follow our instructions, you should have no problem in satisfying biodiversity net gain and securing planning permission from the local authorities across Halton and Merseyside.