SoNaRR 2025: Pollution

Pollution is contaminants and other nuisances in the environment which can harm human health, living organisms or the natural or built environment. These contaminants may be in the form of substances (e.g. chemicals) or energy (e.g. light, noise, radioactivity, heat). These contaminants can directly or indirectly change the biological, thermal, chemical, physical, or radioactive properties of the medium they are in (e.g. water, air, land) in a way that can create a hazard. These may be produced by natural processes and human activity.

Key messages

• While air quality in Wales has improved, pollution still impacts health and ecosystems, making coordinated action under new legislation essential to achieving environmental goals.
• Land and soil pollution incudes atmospheric deposition (e.g. nitrogen, sulphur), land spreading and application or waste disposal (e.g. heavy metals, pesticides, microplastics, nutrients above crop need, fly tipping), and from polluted waters (e.g. runoff, flooding). Contaminants like PFAS, veterinary medicines and other pharmaceuticals are concerning, but evidence on their long-term effects is limited. While some pollutants have declined, others persist or increase locally.
• 40% of Wales’s freshwater and marine bodies achieve good status under the Water Framework Directive regulations, which has not changed since the last SoNaRR report. Significant pressures include wastewater, towns and cities, transport, agriculture and abandoned mines. Growing public concern around impacts of poor water quality highlights how important our freshwater and marine environments are to the people of Wales.
• Noise pollution in Wales is a public health concern, with 25% of residents report being affected, especially in urban areas. New Welsh legislation on soundscapes aims to improve well-being by promoting healthier, more inclusive acoustic environments.
• 18.84% of Wales has a dark sky designation. Although awareness of the opportunities of a night sky and the effects of light pollution are becoming more apparent, light pollution remains a problem across much of Wales. Light pollution disrupts the behaviours of whole ecosystems and migratory birds, which rely on natural darkness. Light pollution where people live can impact human health and wellbeing.
• Strategic interventions, nature-based solutions, and collaborative land and water management are showing some success in restoring ecosystems and reducing pollution, but action must be taken at pace and at scale to manage the sources of pollution and mitigate its impacts.
  
  

Underlying evidence

The SoNaRR 2025 assessment of Pollution is informed by evidence set out in the Pressures for each Natural Resource and Ecosystem. You will find it in the drivers of change and pressures detailed evidence within our interactive Power BI report linked below. All Ecosystems and Natural resources are affected by pollution and have relevant evidence.

Read our Natural Resource and Ecosystem assessments.

Access the detailed evidence through our SoNaRR 2025 Evidence portal.

View full screen version.

Key evidence sources

Explore some of the evidence we have used to inform our assessment:

• Air Quality in Wales Reports
• ERAMMP Report-105: Wales National Trends and Glastir Evaluation 
• Wales Environmental Pollution Incidents 
• Water Watch Wales - Water Framework Directive Maps 
• Tranquillity and Place maps 
• Environmental Noise Mapping 2022
  
  

Case studies

Tranquillity and Place

The nationally consistent terrestrial Tranquillity & Place resource identifies the strategic and local resource in remote, rural, peri-urban and urban areas for use as an evidence base to inform policy intent, practice and provision for well-being benefits.

Tranquillity and Place