Ammonia Assessments in England

In England, Ammonia Assessments are an important tool for managing air quality, particularly where agricultural activities may affect environmentally sensitive areas. They are frequently required as part of the planning process for agricultural developments, including livestock accommodation, slurry and manure storage, and anaerobic digestion facilities.

Updated guidance issued by Natural England in October 2025 sets out clearer expectations for assessing air emissions from new developments where protected sites may be affected. This guidance, produced in line with the Conservation of Habitats and Species Regulations 2017 and the Wildlife and Countryside Act 1981, emphasises the need to assess any proposal that could influence designated ecological sites. These include Special Areas of Conservation, Special Protection Areas, Ramsar sites and Sites of Special Scientific Interest. Where a potential impact is identified, Natural England may request a dedicated Ammonia Assessment to determine whether a proposed agricultural development could adversely affect these sites.

Agricultural ammonia emissions can originate from a wide range of on-farm activities, such as housing livestock, storing organic manures and slurries, and land application or grazing practices. Elevated levels of ammonia are problematic because of their damaging effects on sensitive ecosystems. These impacts can be immediate, such as visible damage to plant tissues and changes in lichen and bryophyte communities, or longer-term and indirect, through increased nitrogen and acid deposition. Such processes can lead to nutrient enrichment, soil degradation, freshwater acidification, and the proliferation of algal blooms. Evaluating ammonia emissions is therefore a key step in protecting biodiversity and preventing harm to sites of high conservation value.

Regional Guidance

Natural England has produced guidance to support the assessment of potential impacts from atmospheric ammonia emissions on designated ecological sites arising from agricultural developments.

The guidance sets out the key assessment stages to be followed when considering potential impacts from a proposed development. These are summarised as follows:

• Screening to determine the proximity of the development to relevant protected ecological designations.
• Quantifying additional ammonia emissions to which a protected site may be exposed as a result of the development, using either the SCAIL tool or detailed atmospheric dispersion modelling.
• Comparing predicted impacts against relevant screening thresholds, both as a standalone development and in combination with other nearby plans and projects.
• Completion of a Detailed Air Quality Impact Assessment if a conclusion of no likely significant effect cannot be reached when comparing impacts against the relevant thresholds.

Redmore Environmental has extensive experience in undertaking Ammonia Assessments in line with Natural England’s guidance and can provide robust, evidence-based evaluations to support planning projects. Assessments can be undertaken for a range of agricultural applications.

The in-house expertise that Redmore Environmental offer provides our clients with confidence that assessments will be undertaken to meet their objectives in line with relevant regulatory guidance. Advice tailored to each application can be provided to help identify suitable mitigation solutions, if required.

Ammonia Assessments in England

Success of your planning applications could be aided by Redmore Environmental’s comprehensive experience of undertaking Ammonia Assessments for developments throughout England. You will gain advice on application approaches and discharging conditions to addressing consultation responses. Throughout England we have been involved in several exciting agricultural projects in recent years. These include:

• Poultry Unit, Seighford – Ammonia Assessment in support of a proposed 64,000-place free-range laying unit on land off Clanford Road, Seighford. The proposals comprised four houses, connected by a central egg packing area, with each providing accommodation for 16,000 birds using an aviary system, as well as an outdoor roaming space. Following submission of the planning application, a scoping response was received from Natural England. This indicated concerns regarding potential impacts on nearby ecological designations as a result of atmospheric emissions from the scheme. Dispersion modelling was therefore undertaken in order to address the relevant comments by quantifying effects in the vicinity of the site. The results indicated impacts to be below relevant thresholds at all sensitive locations.
• Bowden Farm, Sherford – Ammonia Assessment in support of an application for three livestock buildings to facilitate an expansion to current operations at Bowden Farm, Sherford. A consultation response from Natural England indicated a requirement for an assessment to consider potential impacts as a result of ammonia emissions from the development and other nearby proposals on nearby sensitive ecological receptors. An Ammonia Assessment was therefore undertaken which included dispersion modelling of ammonia emissions to determine the impact from the development alone and in-combination. The analysis indicated that ammonia impacts as a result of the operation of the livestock buildings alone and in-combination with were not significant in accordance with relevant guidance. Natural England had no further objection to the application.
• Poultry Unit, Brampton – Ammonia Assessment in support of a proposed free-range laying unit on land at Desoglin, Brampton. The proposals comprised development of a livestock building to provide accommodation for 16,000 birds, kept on a 14-month cycle, as well as 6.4 hectares of outdoor roaming space. The scheme had the potential to affect existing air quality conditions at sensitive ecological receptors. Dispersion modelling was therefore undertaken in order to quantify ammonia concentrations and nitrogen and acid deposition rates at relevant designations, including Special Areas of Conservation, Sites of Special Scientific Interest and Special Protection Areas. The results indicated an acceptable level of emissions from the scheme.

How can we help you?

Redmore Environmental has extensive experience in preparing Ammonia Assessments, as well as wider Ecological Air Quality Assessments, to support a diverse range of agricultural developments across England. Our work has included direct consultation with Natural England in relation to specific planning applications.

Ammonia is just one of several pollutants of concern associated with agricultural activities. Other potential issues include odour, dust, bioaerosols, and emissions from on-farm combustion processes, all of which can impact the health and amenity of nearby communities. Redmore Environmental offers comprehensive assessment services covering all relevant pollutants, ensuring that your application is fully supported by robust evidence.

To discuss your project or learn more about how we can assist with Ammonia Assessments or related air quality issues, contact one of our specialist Air Quality Consultants today.