Timothy Charles Harris, R (on the application of) v Natural England

Under the precautionary approach to nature conservation, a demonstrated risk of deterioration can trigger a duty to take appropriate steps before actual deterioration is established. The risk alone does not make a regulator’s failure to eliminate it an immediate breach: the regulator may need reasonable, fact-specific time to investigate and decide what action is appropriate. That discretion is subject to public law duties and does not permit inaction where the evidence establishes a clear pollution pathway and risk to a protected site. On the evidence in this case, Natural England’s failure to take active protective steps breached its duties under regulation 9(1) and Article 6(2).

The claimant owned part of Catfield Fen, which forms part of a Site of Special Scientific Interest and the wider Broads Special Area of Conservation. Natural England is the statutory nature conservation body for the site. The claimant sought judicial review of its response to nutrient pollution believed to run from neighbouring farmland, across a road and through drainage grips into the Fen.

The claim alleged breach of regulation 9(1) of the Conservation of Habitats and Species Regulations 2017 and Article 6(2) of the Habitats Directive. The claimant argued first that breach arose once Natural England knew of the risk and failed to act immediately, and alternatively that its response was irrational. The central issues were when the duties required action and whether Natural England’s response was sufficient.

1. The court rejected the claimant’s first argument. A risk of harm can trigger the protective duty, but breach does not arise automatically as soon as a regulator receives notice of that risk. A regulator must have time to investigate and determine appropriate steps. The time reasonably required is fact-specific and depends in part on whether the required work is an initial risk assessment or the selection of substantive interventions.

2. The precautionary principle applies when interpreting the duties under the Conservation of Habitats and Species Regulations 2017 and the Habitats Directive. CG Fry v Secretary of State for Housing Communities and Local Government [2025] UKSC 35 concerned procedural assessment duties, but its discussion did not make the current issue of substantive protective action automatic. Grune Liga Sachsen v Freistaat Sachsen [2016] PTSR 1240 and R (Harris) v Environment Agency [2022] EWHC 2264 establish that risk, rather than proven deterioration, can trigger the duty to take appropriate steps.

3. What steps are appropriate is a matter of regulatory judgment, subject to ordinary public law duties. The duty may initially require further investigation. But the discretion over the choice and timing of measures does not permit a regulator to take no steps where the evidence establishes a risk requiring action.

4. Here, Natural England had known of the risk for years. The evidence established nutrient exceedances, a clear runoff pathway from Mr Alston’s land through the grips, and hydrological connection to the wider Fen. Natural England accepted the relevant risk, yet had not put effective mitigation in place and had delayed its own effective survey. The court held that further investigation alone was insufficient and found a breach of regulation 9(1) and Article 6(2). The specific protective measures, and any further orders, were left for further submissions.