Nash (t/as RG Nash & Sons) v Secretary of State for the Environment, Food & Rural Affairs

Factual and Procedural Background

This appeal concerns land at Brighthams Farm in West Sussex that drains into the River Adur. The Secretary of State for the Environment, Food & Rural Affairs (the Respondent) served a notice proposing to designate this land as a relevant holding within Nitrate Vulnerable Zone (NVZ) number S522 under the Nitrate Pollution Prevention Regulations 2015. The designation imposes restrictions on nitrogen fertiliser use and organic manure storage to prevent nitrate pollution in waterways.

The Appellant, represented by an independent environmental consultancy, challenges the designation on the basis that the water into which the land drains was wrongly identified as polluted. The appeal was conducted without a hearing, with both parties submitting evidence and arguments in writing. The Tribunal was tasked with determining whether the Secretary of State was correct to identify the water as polluted and thus properly designate the land as an NVZ.

Legal Issues Presented

1. Whether the Secretary of State was wrong to identify the water draining the land as polluted for the purposes of NVZ designation under the Nitrate Pollution Prevention Regulations 2015.
2. Whether agriculture makes a significant contribution to nitrate pollution in the water body sufficient to justify NVZ designation.

Arguments of the Parties

Appellant's Arguments

• The monitoring points used to designate the NVZ were unduly influenced by discharges from a wastewater treatment works (WWTW), overstating agricultural contributions.
• Data collected during low flow conditions was improperly included, skewing pollution assessments.
• No land use modelling was conducted contrary to the prescribed Methodology, undermining confidence in the designation.
• The failure to consider ammonia as part of Total Inorganic Nitrogen (TIN) further reduced confidence in the pollution assessment.
• The Environment Agency’s reliance on land cover data and the SEPARATE model to estimate agricultural contribution was flawed and not corroborated.
• The increasing trend in TIN concentrations despite acknowledged reductions in agricultural nitrate leaching suggests point sources dominate pollution.
• SIMCAT modelling, which could clarify agricultural contributions, was not provided.
• Overall, the evidence does not support the conclusion that agriculture makes a meaningful contribution to pollution at the relevant monitoring points.

Respondent's Arguments

• The Secretary of State, through the Environment Agency, relied primarily on monitoring data to identify pollution and designate the NVZ.
• The Environment Agency asserted that land cover data showing about 60% agricultural land corroborated the SEPARATE model estimating a 51% agricultural contribution to nitrogen load.
• The Environment Agency maintained that the monitoring points passed required methodological checks and that the designation was justified despite the absence of land use modelling for this NVZ size.
• The Environment Agency argued that contributions from the point source (WWTW) still allow for a substantial agricultural contribution.
• The omission of SEPARATE model outputs from the datasheet was described as an oversight but did not affect the proper application of the Methodology.

Table of Precedents Cited

Court's Reasoning and Analysis

The Tribunal’s principal task was to determine whether the Secretary of State was wrong to identify the water draining the land as polluted, applying a standard of review that accords substantial weight to the Environment Agency’s expertise and decision-making authority.

The Tribunal identified significant evidential deficiencies undermining the designation. Notably, the Environment Agency relied solely on monitoring data without conducting or properly applying land use modelling as required by its own Methodology. The omission of SEPARATE model outputs from official datasheets was deemed an unexplained oversight, further eroding confidence in the evidential basis.

The Tribunal found the Environment Agency’s reliance on land cover data and the SEPARATE model to estimate agricultural contributions unconvincing, particularly given the evidence that point source pollution from the WWTW was underestimated. The increasing nitrate trend despite acknowledged reductions in agricultural leaching suggested that point sources dominated pollution.

The Tribunal agreed with the Appellant that the inclusion of low-flow data distorted pollution assessments and that ammonia, a component of TIN, was not accounted for, contrary to the Methodology’s guidance. The absence of SIMCAT modelling, which could have clarified agricultural contributions, was a significant gap.

Given these evidential frailties, the Tribunal concluded that the Secretary of State lacked a proper evidential basis to determine that agriculture made a meaningful or significant contribution to nitrate pollution in the water body. The possibility that future, more robust evidence could support designation was acknowledged, but on the current record the designation was not justified.

Holding and Implications

The Tribunal’s final decision is that the appeal is ALLOWED.

This means the Secretary of State’s designation of the land at Brighthams Farm as a relevant holding within NVZ S522 is quashed on the basis that the water was wrongly identified as polluted due to insufficient and unreliable evidence of significant agricultural contribution to nitrate pollution.

The direct effect is that the Appellant is relieved from the regulatory restrictions imposed by the NVZ designation at this time. The decision does not establish new legal precedent but underscores the necessity of a robust evidential basis—including appropriate modelling and consideration of all nitrogen components—before designating NVZs.