In recent years, air quality in Mumbai has significantly declined, raising serious health and environmental concerns. Reports indicate a 305% rise in air-pollution-related complaints over the last five years, with studies suggesting a 30% increase in pollution. Key factors contributing to this deterioration include complex weather conditions, such as La Nina, which slows down the wind movement and traps pollutants, along with emissions from local sources and pollutants from neighbouring areas.
Over the years, managing air quality within a city’s boundaries has been proven to have limited impact only. Scientific evidence shows that pollution from one area can travel to other parts due to meteorological factors, impacting local air quality across regions. The answer to this problem lies in adopting an airshed-level governance framework.
This implies an approach for air quality management that considers an entire airshed — a geographic area where pollutants get trapped, creating similar air quality for everyone — regardless of administrative or political boundaries. Such a framework enables coordinated, cross-jurisdictional efforts to effectively tackle pollution and improve air quality within the entire airshed.
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Mumbai airshed area management
The Mumbai Metropolitan Region (MMR) spans 18 municipal corporations and councils, a nagar panchayat and several villages. While cities such as Mumbai, Thane, Mira-Bhayandar and Navi Mumbai within MMR have each adopted measures for reducing dust arising from construction sites and vehicular emissions, these fragmented efforts lack holistic planning, resources and data-sharing needed for large-scale impact.
Mumbai’s airshed region has not been scientifically defined and requires comprehensive study. Some studies do, however, suggest the existence of a “western airshed” encompassing MMR, Pune and parts of Gujarat. A World Bank study talks about dividing India into six broad airsheds, but these definitions remain preliminary too. An airshed-level management body for MMR could take the lead in conducting detailed research to accurately delineate Mumbai’s airshed region.
Such an entity could further strengthen collaboration among key stakeholders — government agencies, industry players and civil society. It can help identify and understand the urban and rural areas that constitute the larger airshed of the region, facilitate shared infrastructure development, expand data collection and monitoring, and streamline policymaking.
This would also enable smaller municipalities with limited resources to gain access to pooled resources, technical support and unified policy frameworks. Agencies lacking in-house expertise could also benefit. Additionally, consolidated funding from sources like the National Clean Air Programme (NCAP), the XV Finance Commission and state contributions can streamline financing, enhancing the impact of air quality initiatives across the region.
Airshed approach: What other cities have seen
There are several global examples to illustrate the long-term impact of airshed-level governance. The California Air Resources Board was established over five decades ago to improve the state’s deteriorating air quality. The board focused on creating targeted action plans for ‘Air Districts’ and ‘Air Basins’ that it identified with similar geographic and meteorological conditions in the region. The air quality regulations and strategies were tailored to address specific pollution sources.
Another example comes from Mexico City, where the Metropolitan Area of Mexico City encapsulates an airshed-based approach. Cross jurisdictional collaboration among local and regional authorities, advisory committees and research paved the way for effective regulation in Mexico City. Measures like vehicle inspections to enforce emission standards and ‘no-driving days’, uniformly implemented across the airshed area for the city, contributed to reducing pollution from various sources (including vehicle emissions).
India’s Commission on Air Quality Management (CAQM), formed in 2021 to oversee air quality management in Delhi and the National Capital Region, has made significant strides in coordinated air quality monitoring, regulation and enforcement. The CAQM holds authority to act across neighbouring states, including Haryana, Uttar Pradesh, Punjab, and Rajasthan, enabling it to address pollution issues beyond state boundaries. Its flying squads monitor and curb polluting industries, ensuring compliance with environmental regulations. The commission facilitates the development of coordinated action plans with state governments and promotes research and innovation to improve air quality across the region.
What an airshed approach could do for Mumbai
As home to the country’s largest port and key economic centres, Mumbai is a hub for transportation and consequently, a significant source of emissions. Achieving meaningful reductions will require coordinated policy and strategic planning at a regional scale, ensuring that economic growth aligns with the region’s air quality and climate goals.
NITI Aayog’s recently released economic master plan for MMR also stresses on how Mumbai needs to focus on creating a plan to achieve an over 40% reduction in monthly peak AQI to “create a liveable city and attract talent.”
Read more: Mumbai’s pollution: A huge health epidemic
Mumbai has already launched its Mumbai Climate Action Plan, setting a model for city-level climate strategies across India. There is an opportunity now to establish Mumbai as a best-practice example by creating a strong, legally backed institutional set-up with the power to regulate and enforce measures that improve air quality across MMR. An institution such as this could coordinate efforts across cities, elevate air quality as a regional priority and work toward a shared vision. This would enable sustained and enforceable actions to address air pollution at its source.
Reducing emissions also requires systemic changes, including investment in shared public transportation, expansion of electric vehicle infrastructure and promotion of sustainable development to balance economic and environmental priorities across MMR. While many of these solutions can be rolled out at the city level, coordinated and unified actions will yield a far greater impact. Isolated efforts are insufficient, as pollution travels across the region, undermining localised progress.
Improving air quality is a long-term commitment that demands robust institutional frameworks, supported by both state and central governments. Sustainable progress can only be achieved through an airshed-based approach, with a clear mandate for integrated planning and coordinated action across the entire region.