How has Brexit Impacted the UK’s Environmental Protection – with Specific Reference to the OEP under the Environment Act 2021

Post by Raya Abboud

Brexit, one of the most pivotal moments in the UK’s recent history, was the UK’s departure from the EU in January 2020, following the 2016 referendum, which saw a 52% majority vote to leave. Brexit aimed to restore national sovereignty and establish independent policies (Wallenfeldt, 2022). Under the EU’s control, the UK was bound to follow established standards regarding topics concerning air quality, waste, and biodiversity (The EU Referendum and the UK Environment: An Expert Review Executive Summary, n.d.). However, after Brexit, the UK no longer faced EU institutional oversight of environmental law as the administrative framework that allowed the EU to enforce such standards had been dismantled (UKELA, 2017). This process involved the UK cutting ties with the European Commission and the Court of Justice of the European Union (CJEU), thereby ending direct oversight and weakening the legal principles that had previously protected environmental standards. The Office for Environmental Protection (OEP) was established under the Environment Act 2021 to replace the oversight the EU had before Brexit. OEP operates in England and Northern Ireland, and it holds government and public authorities accountable for environmental law compliance through monitoring and enforcement (The Office for Environmental Protection, 2024). However, the question remains: has Brexit strengthened or weakened environmental protection?

One of the most notable consequences of Brexit for UK environmental protection was the loss of the EU’s enforcement mechanisms. While part of the EU, the UK was subject to the European Commission and the Court of Justice of the EU, which investigated violations and imposed penalties when member states failed to comply with environmental obligations. The Commission also brought extensive technical expertise through agencies like the European Environment Agency and the European Food Safety Authority, which set standards. Post-Brexit, these institutional frameworks no longer apply to the UK, creating a governance gap that domestic law was unable to fully address (Client Earth, 2022). To fill that gap, the Environment Act 2021 established the OEP – they were tasked with monitoring and reporting on how environmental laws are implemented, advising the government, and investigating complaints. OEP also introduced a legal duty on ministers to have due regard to environmental principles such as the precautionary and polluter-pays principles (Department for Environment, Food & Rural Affairs, 2025).

While this structure did provide a form of domestic oversight, its enforcement powers are deemed to be weaker than the EU equivalents. This is because courts can issue statements of non-compliance but generally cannot impose penalties or require remedial action in the way the EUCJ could under EU law (Client Earth, 2021).

Recently, monitoring by the OEP suggests that environmental laws are not being implemented effectively, especially in key areas like water quality. For instance, an OEP report has found that government plans are far off track from achieving targets for rivers, lakes, and coastal waters, with the worst-case scenario estimating only about 21% of surface water reaching “good ecological status” by 2027. This is a goal transferred from the former Water Framework Directive (Office for Environmental Protection, 2024). This emphasizes wider concerns regarding the effectiveness of the enforcement: without the EU’s mandatory standards and strict sanctioning, implementation has been lacking, and monitoring is taking place less often. As well as this, analysis shows that the UK is falling behind the EU in updating environmental protections, with the new EU laws on habitats, water, air, and waste not being adopted in the UK. This divergence has become evident in recent critiques of UK water and chemical regulation, which are described as weaker than in many EU countries (Horton, 2025).

Despite such drawbacks, the post-Brexit framework is not without merit. The OEP’s obligation to report to Parliament means that there is more transparency and domestic accountability (Department for Environment, Food & Rural Affairs, 2025). The Environment Act also mandates legally binding environmental targets on air, water, and biodiversity – giving policymakers long-term goals to work toward (Department for Environment, Food & Rural Affairs, 2025). This was something that was not present under EU law. However, it is argued that without strong enforcement mechanisms and enough resourcing, such targets set under the Environment Act 2021 risk not being met. The UK’s ability to set such policies offers flexibility but also raises the possibility of regulatory regression due to the absence of external pressure, which was once exerted by the EU.

Reference list

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Department for Environment, Food & Rural Affairs (2025a). Government response to the Office for Environmental Protection review of implementation of the duty to have due regard to the Environmental Principles Policy Statement in England. [online] gov.uk. Available at: https://www.gov.uk/government/publications/government-response-to-oep-review-implementation-of-the-duty-to-have-due-regard-to-the-environmental-principles-policy-statement/government-response-to-the-office-for-environmental-protection-review-of-implementation-of-the-duty-to-have-due-regard-to-the-environmental-principles? [Accessed 4 Feb. 2026].

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