Defra’s post-legislative review of the Environment Act 2021 concludes that the Act has largely succeeded in putting its intended governance framework in place, but that implementation remains incomplete in several important areas. Published on 3 November 2026, the memorandum is a five-year assessment of how the legislation has operated since Royal Assent.
For developers, infrastructure promoters, waste operators, water companies, landowners and public bodies, the central message is not that a new set of immediate duties has been created. Rather, it is that the legal architecture introduced by the Act is now firmly established, while several delivery mechanisms, secondary regulations, datasets and long-term outcomes are still developing.
The review is primarily concerned with England, although some provisions apply more widely or have separate arrangements in the devolved nations. Organisations should therefore continue to check the territorial application of individual requirements rather than treating the Act as a single UK-wide compliance regime.
Framework established, outcomes not yet proven
Defra considers that the Act has delivered the principal structures Parliament intended: statutory environmental targets, Environmental Improvement Plans, annual reporting, environmental monitoring duties and the Office for Environmental Protection’s oversight role. It also points to the Environmental Principles Policy Statement as a cross-government mechanism for considering environmental effects in policy development.
However, the memorandum repeatedly distinguishes between establishing powers and systems, and demonstrating environmental improvement in practice. Data can take years to collect and interpret, while outcomes in habitats, water quality and air pollution will often follow investment and regulatory action only after a considerable delay.
This matters in planning and environmental due diligence. The existence of a target, plan or new statutory power does not automatically translate into a site-specific consent condition, permit requirement or enforcement action. Equally, incomplete evidence should not be read as a signal that regulators will relax existing requirements. The review instead suggests that scrutiny will increasingly focus on whether policy commitments are being converted into workable delivery and measurable results.
Waste reforms are moving from legislation into operation
The waste and resources sections of the Act underpin major reforms including packaging extended producer responsibility, deposit return arrangements, consistent recycling collections and digital waste tracking. Defra’s assessment is that several of these measures are either recently operational or not fully commenced, so it is too early to judge their effectiveness.
For businesses handling construction, commercial, excavation or remediation wastes, the most immediate practical change is digital waste tracking. The memorandum records that the first regulations for England, Scotland and Wales were made in 2026, with the English and Welsh system due to begin in October 2026 and Scottish implementation following in January 2027. Businesses should ensure that waste descriptions, classifications, carriers, receiving facilities and transfer information can be consistently recorded through their operating systems and supply chain.
Separate collection reforms also remain phased. The review notes that obligations for businesses took effect from 31 March 2025, while local-authority arrangements were delayed until 31 March 2026. Microfirms have a later compliance date of 31 March 2027. These dates are relevant to occupiers, facilities managers, contractors and developers designing operational waste-storage arrangements for new schemes.
Water planning has advanced, but key effects are longer term
In water, the review highlights the statutory footing given to Drainage and Sewerage Management Plans. These plans are intended to improve how sewerage undertakers assess capacity, flood risk, wastewater pressures and future infrastructure needs. The first statutory round is under preparation, with final plans expected by the end of August 2028 to inform Ofwat’s 2029 price review.
That timetable is important for strategic development, especially in catchments where wastewater capacity, surface-water management or storm-overflow performance is already a planning constraint. It does not itself change the drainage evidence needed for a live planning application. However, promoters of larger or phased schemes should allow for greater attention to long-term wastewater capacity, site drainage, phasing assumptions and collaboration with water companies.
Defra also identifies provisions that have not yet commenced or are only partly in force, including measures associated with water-resources planning and some monitoring duties. The review therefore does not claim that the full water package has been delivered.
Biodiversity duties are embedded, with implementation still being refined
The review is positive about the new nature-recovery tools created or strengthened through the Act, including the biodiversity duty on public authorities, Local Nature Recovery Strategies, conservation covenants and biodiversity net gain. For most Town and Country Planning Act development in England, mandatory biodiversity net gain has been in force since 2024. Its extension to nationally significant infrastructure projects began on 2 November 2026.
Yet Defra recognises continuing challenges around local-authority capacity, monitoring, publication timetables and the time required before ecological outcomes can be measured. It also records that government has adjusted the biodiversity net gain framework following consultation, including changes affecting certain minor and brownfield development.
Applicants should therefore avoid relying on early-stage assumptions about exemptions, the biodiversity metric, off-site delivery or the availability of registered gains. A proportionate baseline survey, an early biodiversity gain strategy and realistic long-term management and reporting arrangements remain important to programme certainty.
What organisations should consider now
- Track implementation instruments: distinguish the Environment Act’s enabling provisions from regulations, guidance and commencement dates that create operational duties.
- Strengthen evidence trails: retain clear records for waste movements, biodiversity calculations, drainage design decisions and environmental permit compliance.
- Review project assumptions: check that planning, infrastructure and operational programmes reflect current biodiversity net gain, waste-tracking and collection requirements.
- Engage early on capacity constraints: for large developments, test wastewater, drainage and off-site biodiversity delivery assumptions before they become critical path issues.
- Expect continued scrutiny: the Office for Environmental Protection has separately warned that government remains off track on key environmental commitments, reinforcing the likelihood of further policy refinement and closer attention to delivery.
The review is best read as a progress report on a live regulatory programme rather than a conclusion to it. The Environment Act’s framework is now part of the compliance landscape, but its practical effect will continue to be shaped by secondary legislation, guidance, regulator capacity, investment cycles and the quality of environmental monitoring over the coming years.