Does the UK need a Catchment Based Approach for air quality monitoring?

The UK’s Catchment Based Approach (CaBA) has revolutionised how water environments are monitored and managed: locally led, multi-stakeholder partnerships that integrate citizen science, professional instrumentation, and policy coordination.

But while water monitoring has a clear grassroots governance structure, air quality monitoring remains fragmented, compliance-driven, and often siloed.  

Could air quality benefit from its own version of CaBA – and is there any evidence from elsewhere that it works?

The case for a place-based, collaborative approach

Air pollution is a social and spatial issue with a high degree of variability, even on a neighbourhood-by-neighbourhood level.  

Urban traffic corridors, industrial sites, and disadvantaged communities all face distinct exposure patterns.  

Yet UK air quality management is largely structured through Local Air Quality Management (LAQM), which requires councils to identify problem areas and draw up action plans.  

While technically sound, LAQM is bureaucratic, inconsistent across regions, and rarely empowers communities or leverages the full potential of monitoring networks.

Instrument suppliers and environmental consultants know that data isn't enough on its own; uptake, interpretation, and community trust are just as critical.

A CaBA-style model could fill that gap by:

• Creating standing partnerships that unite local authorities, universities, NGOs, public health bodies, and residents.
• Pooling resources to deploy networks of calibrated low-cost sensors alongside reference instruments.
• Feeding granular data into wider regional and national policy frameworks.

But would it work?

Lessons from the international community

Several international initiatives suggest that collaborative, place-based air monitoring can succeed but also reveal challenges.

United States: community air monitoring under EJ initiatives

The US EPA funds Community Air Monitoring Projects under its Environmental Justice (EJ) program.  

These initiatives place calibrated sensors in underserved communities, often managed in partnership with local groups and technical partners.

For example, the South Coast AQMD in California has piloted community-based air monitoring programs using a hybrid of regulatory-grade and low-cost instruments.

These projects improve public trust and help identify pollution hot spots that don’t register in standard monitoring.

Takeaway: Community partnership increases relevance and coverage, but long-term funding and technical consistency remain a hurdle.

Netherlands: Samen Meten (Measuring Together)

The Dutch National Institute for Public Health and the Environment (RIVM) runs the Samen Meten programme, a network of citizen and institutional monitors.  

Data is shared through a national platform that integrates public observations with official air quality data.

Takeaway: Institutional support for participatory monitoring can be technically robust and nationally integrated — something the UK would need to emulate.

India: Sensor Networks and Local Planning

In cities like Bengaluru and Delhi, projects led by academic institutes (e.g. CSTEP, UrbanEmissions) have deployed dense sensor arrays in collaboration with municipal authorities.  

The data supports health impact studies and local interventions such as traffic rerouting or industrial permitting.

Takeaway: In data-scarce settings, collaborative sensor-based projects have had real policy impact — but require strong local technical capacity.

What would a CaBA for air quality look like?

A Catchment Based Approach for air quality would likely take the form of locally rooted partnerships, perhaps called Regional Air Partnerships, bringing together councils, public health authorities, community organisations, universities, and private sector actors, including instrumentation providers.  

These partnerships would coordinate air quality monitoring efforts, develop shared priorities, and foster public engagement, mirroring the collaborative ethos of CaBA's catchment management.

A defining feature would be the integration of different monitoring technologies.  

This includes traditional reference-grade stations alongside networks of professionally supported low-cost sensors deployed in schools, residential areas, and industrial corridors.  

These sensors would generate fine-grained data to supplement regulatory observations and fill critical spatial gaps, especially in areas where official stations are too sparse to capture localised pollution.

Data sharing and interpretation would be central to this approach.  

A national platform, analogous to CaBA’s data hub, could collate, visualise, and contextualise both statutory and community-generated data, helping to inform real-time responses and long-term planning.  

Such a system would support not only regulatory compliance but also local interventions: rerouting traffic, modifying planning decisions, or tailoring public health messaging.

Crucially, this model would bridge the disconnect between monitoring and action.  

By embedding air quality monitoring within a cross-sectoral partnership structure, a CaBA-style framework could ensure that air data doesn’t just sit in dashboards but translates into coordinated, community-relevant decision-making.