Insights from the Office of Environmental Protection’s First Decision Notices
Planning and Environment, Public Law and Judicial Review

The Office of Environmental Protection (‘OEP’), which has enforcement powers in respect of public authorities under Chapter 2 of Part 1 of the Environment Act 2021, has issued three decision notices to the Department for Environment, Food and Rural Affairs (‘Defra), the Environment Agency (‘EA’) and the Water Services Regulation Authority (‘Ofwat’) respectively. These are the first decisions notices that have been issued by the OEP and they raise interesting public law questions (for example, around the duty to take enforcement action and overlapping regulatory obligations), as well as casting light on how the OEP is approaching its role in enforcing compliance with environmental law.
The notices relate to an ongoing investigation into the discharge of untreated sewage by water companies into the watercourses in the UK, which has been an issue of significant public debate and interest in the last decade. Recently, the Supreme Court ruled that water companies may be liable under private law for such discharges. Now, the OEP has shown that, as a matter of public environmental law, the OEP will hold public authorities to account where there have been serious failures to comply with environmental law. This is a significant development because the OEP has replaced the EU Commission following the UK’s exit from the European Union and indicates that the OEP will be able to provide effective oversight over the UK’s compliance with public environmental law.
The issuing of these decision notices also indicates that it may be an effective strategy for NGOs, charities and community groups to compile evidence of non-compliance with environmental law and submit this to the OEP for investigation. This will be particularly relevant where the breach of environmental law is procedural, such as the failure to review the effectiveness of measures or to adopt a plan, or where a group or individual is insufficiently resourced to bring their own judicial review challenge.
The Investigations
The decision notices were issued following an investigation initiated in June 2022 into the regulation of network combined sewer overflows under section 33 of the Environment Act 2021. The investigation was launched in response to a complaint received by Salmon & Trout Conservation UK, now known as WildFish. The OEP states that “[t]he aims of the OEP investigation are to clarify the roles and responsibilities of the public authorities and to determine whether they have failed to comply with their respective duties. If there have been failures, the OEP will seek to improve regulation in order to achieve long term improvement in water quality.”
The statutory criteria for issuing a decision notice under section 36(1) of the Environment Act 2021 are that the OEP must be “satisfied, on the balance of probabilities, that the authority has failed to comply with environmental law” and that the OEP “considers that the failure is serious”. If these authorities do not respond to, and address the steps set out in, the decision notices, the OEP may bring an environmental review against these authorities under section 38 of the Environment Act 2021. Helen Venn, the OEP’s Chief Regulatory Officer, has said “We will decide next steps when we have considered the responses to these decision notices. That could include court action.”
Helen Venn also noted that Defra, the EA and Ofwat had already taken “positive steps taken to address the issues identified” and Defra provided a press release in response to the decision notices reiterating the positive steps that had been taken. These steps were, however, not sufficient to avoid the OEP issuing the decision notices.
Details of the Defra Decision Notice
The decision notice sent to Defra indicated:
The OEP investigation has concluded that there have been three failures to comply with environmental law by Defra:
- Failing to take proper account of environmental law by:
- Drafting guidance for water companies and regulators which did not reflect the true legal extent of sewerage undertaker duties
- Failing to amend or replace the guidance after a relevant Court of Justice of the European Union (CJEU) decision in 2012
- Misunderstanding its legal duty under environmental law to make enforcement orders
- Failing to exercise its duty under environmental law to make enforcement orders
- Failing to discharge its duty to secure compliance with environmental law relating to emissions controls
The recommended steps to remedy, mitigate or prevent reoccurrence of the failures include revising the guidance, ensuring delegated responsibilities are carried out properly, agreeing Memorandums of Understanding (MoUs) with the EA and Ofwat and ensuring that permits for CSOs are amended appropriately.
In relation to the first failure identified above, the OEP acknowledges Defra’s recent consultation on updated guidance for regulators and water companies and awaits the outcome of this process. The OEP considers that the third failure listed above ended on 31 December 2020 following the UK’s withdrawal from the European Union.
The relevant environmental law is contained in sections 18 and 94 of the Water Industry Act 1991 (as supplemented by the Urban Waste Water Treatment Regulations 1994 which implement the Urban Waste Water Treatment Directive 1991 ((91/271/EEC)) and the Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 which implement the Water Framework Directive 2000 (2000/60/EC).
Section 18 of the Water Industry Act 1991 sets out a power for the Secretary of State to take enforcement action against a sewerage undertaker for the breach of a condition of an appointment or license or any other statutory requirements. Section 84 sets out the general duty for sewerage undertakers to provide an effective system of public sewers, which includes improving and extending those systems.
The Urban Waste Water Treatment Regulations 1994 provides for various obligations relating to the discharge of urban waste water and, in particular, requires that collecting systems for sewage are required to, in accordance with the best technical knowledge not entailing excessive costs, limit the pollution of receiving water due to storm water overflows.
The Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 sets out the duties and powers in relation to the management of river basis and protected areas of water, including bodies of water for the abstraction of drinking water.
Details of the Ofwat Decision Notice
The decision notice sent to Ofwat indicated:
The OEP investigation has concluded that there have been two failures to comply with environmental law by Ofwat:
- Failing to take proper account of environmental law with regards to duties on sewerage companies and its duty to make enforcement orders.
- Failing to exercise its duty under environmental law to make enforcement orders.
The recommended steps to remedy, mitigate or prevent reoccurrence of the failures include updating enforcement guidance, agreeing and publishing a new MoU with the EA, ensuring relevant responsibilities are carried out properly and making sure that appropriate assessments have been carried out on CSOs and time-bound plans are in place for any improvement schemes to be implemented.
The OEP considers that Ofwat’s approach now takes proper account of environmental law and that the first failure identified above is no longer ongoing. Regarding the second failure, the OEP acknowledges the draft enforcement orders proposed by Ofwat and awaits the outcome of its consultation process and ongoing investigations.
The relevant environmental law is the same as for the Defra notice: ss.18 and 94 of the Water Industry Act 1991 (as extended by the Urban Waste Water Treatment Regulations 1994).
Details of the EA Decision Notice
The decision notice sent to the EA indicated:
The OEP investigation has concluded that there have been three failures to comply with environmental law by the EA:
- Failing to take proper account of environmental law in devising guidance relating to permit conditions
- (As a result of the point above) setting permit conditions that were insufficient to comply with environmental laws
- Failing to exercise permit review functions in relation to discharges from CSOs
The recommended steps to remedy, mitigate or prevent reoccurrence of the failures include updating the Storm Overflow Assessment Framework and any guidance relating to CSO permit setting, agreeing MoUs with Defra and Ofwat, ensuring CSO permits comply with the appropriate regulations and assessment findings.
In relation to the first failure identified above, the OEP acknowledges the EA’s recent consultation on an updated SOAF and awaits the outcome of this process.
The relevant environmental law is the Urban Waste Water Treatment (England and Wales) Regulations 1994, the Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 and the Environmental Permitting (England and Wales) Regulations 2016.
The Urban Waste Water Treatment (England and Wales) Regulations 1994, the Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 are addressed above. The Environmental Permitting (England and Wales) Regulations 2016 sets out a scheme for the licensing of activities which impact the environment, which includes water discharge activities.
Comment
While the decision notices are not in the public domain, the OEP’s announcement demonstrates two interesting public law developments. First, the OEP’s decision notices refer not only to “ordinary” grounds of public law error, for example, the failure properly to represent environmental law obligations when drafting policy (see e.g. R. (A) v Secretary of State for the Home Department [2021] UKSC 37; [2021] 1 W.L.R. 3931 at §38), but also the broader failure to comply with the duty to take enforcement action.
The duty to take action in the context of environmental and climate law is a continually developing area: see in the human rights context, Lopez Ostra v Spain (A/303-C) (1995) 20 E.H.R.R. 277 (environmental licensing and pollution), Verein KlimaSeniorinnen Schweiz v Switzerland (53600/20) [2024] 4 WLUK 614 (reduction of carbon emissions); and in the EU law context, R (WWF-UK and ors) v SSEFRA and another [2021] EWHC 1870 (Admin) [2022] PTSR 1006 (designation of water protection zones under the Water Resources Act 1991), Harris v Environment Agency [2022] EWHC 2264 (Admin) [2022] P.T.S.R. 1751 (water abstraction and the Habitats Directive), the Client Earth litigation (Air Quality Directive).
In the context of network combined sewer overflows, the relevant legal duties to take enforcement are likely to be under regulation 3 of the Water Environment (Water Framework Directive) (England and Wales) Regulations 2017 for Defra and the EA and section 18 of the Water Industry Act 1991 for Ofwat. Each of these duties require the relevant public authority to enforce compliance with retained EU law on water quality for the Defra and the EA or compliance with licensing conditions for Ofwat. The OEP’s decision notices indicate that the circumstances around the discharge of untreated sewage by water companies have reached such a level of severity and seriousness that the failure to act amounts to a breach of these duties to take enforcement action.
A second interesting observation that arises from the decision notices is the question of overlapping obligations. In Harris v Environment Agency [2022] PTSR 1751, [2022] EWHC 2264 (Admin), Johnson J held at §§84-87 that, in the context of the Habitats Directive, “the Environment Agency is one part of a complex regulatory structure and, depending on the issue, it may have a greater or lesser role to play”, but that the EA was” the sole (and certainly the principal) public body which is responsible for determining whether abstraction licences should be granted, varied, or revoked”. It is in this context that memoranda of understanding become important to delineate the respective responsibilities of different regulators.
The three decisions notices require the production and agreement of memoranda of understanding between Defra, the EA and Ofwat to ensure that combined sewer overflows permits comply with the relevant regulatory law. The memoranda of understanding would ensure that these three authorities consider the extent of their powers, where they overlap and how they should co-ordinate or allow a particular body take the lead in relation to amendment of the permits and enforcement. It may be, applying the reasoning in Harris, that Ofwat is to take the lead in ensuring that the permits include the necessary conditions and requirements to align with the Water Framework Directive (etc), with input from Defra and the EA, that the EA and Defra will assist with any input into the assessment of compliance with those conditions and requirements but that the onus for determining whether permits should be granted, varied or revoked falls on Ofwat. We shall have to wait and see whether this is what transpires.
About the Author
Jeremy Ogilvie-Harris is a public law and human rights barristers at Cornerstone. He has experience of advising, assisting and/or representing individuals, campaign groups and local authorities on planning, environment and climate issues. Prior to joining Cornerstone, Jeremy worked at Southwark Law Centre running their Planning Voice Project which assisted individuals and campaign groups to participate in the planning process and was Public Law Supervisor at Hackney Community Law Centre. He has written about his experiences for Legal Action Group.