Supreme Court reviews CAQM’s scientific roadmap on Delhi-NCR air pollution, but gaps remain
The Supreme Court has taken note of a detailed scientific roadmap submitted by the Commission for Air Quality Management on tackling air pollution in Delhi-NCR
The plan focuses on fixing data gaps and building a high-resolution emissions framework to guide future regulation
Experts say the approach marks a shift towards structural reform rather than short-term restrictions
However, the roadmap leaves key questions unanswered on thermal power plants, timelines and enforcement capacity
In the long-running MC Mehta vs Union of India & Others case of 1985, the Supreme Court of India on January 6, 2026 took note of a detailed status report submitted by the Commission for Air Quality Management (CAQM). The report set out the scientific reasoning and institutional steps being pursued to tackle air pollution in Delhi and National Capital Region (NCR).
Filed on January 20, 2026, the report follows a series of meetings of a CAQM-appointed expert group made up of scientists, academics and technical specialists. The group met four times between January 8 and 14, 2026 to review existing evidence on pollution sources, identify methodological weaknesses and advise on longer-term solutions.
The science behind the assessment
The expert group carried out a comprehensive review of source apportionment and emission inventory studies conducted in Delhi-NCR between 2015 and 2025. These studies, produced by different institutions using varied methodologies, were found to differ sharply in their estimates due to inconsistent emission factors, outdated activity data, and differing modelling assumptions.
Despite these limitations, the review confirmed that industrial emissions — both from combustion and industrial processes — remain a major contributor to PM2.5 pollution. These emissions also play a significant role in forming secondary particulate matter through precursor gases such as sulphur dioxide (SO₂) and nitrogen oxides (NOx).
Seasonal factors, particularly winter meteorology, were found to intensify the impact of these emissions.
Need for a structural reform
Rather than recommending immediate, sector-specific restrictions, CAQM has argued that foundational weaknesses must first be fixed. The report noted that earlier regulatory measures often failed because they were based on coarse or unreliable emissions data, resulting in poorly targeted enforcement and limited gains.
To address this, the commission has proposed creating a high-resolution emissions inventory and source apportionment framework for the entire NCR, mapped on a 500 metre × 500 metre grid. This system would combine updated activity data, improved emission factors and advanced dispersion models to help authorities pinpoint pollution hotspots more accurately and design targeted regulatory interventions.
What the report gets right — and where it falls short
The status report lays out several evidence-based steps towards systemic air quality reform. However, a closer look at the proposed “long-term measures” reveals notable gaps, particularly around existing thermal power plants (TPP), and a lack of firm timelines for many of the most ambitious proposals.
The following table provides a detailed breakdown of the components, processes, and measures described in the report.
What the report does not resolve
Despite the depth of its analysis, the report leaves several substantive issues unresolved. While it refers to a proposed restriction on establishing new coal-based TPPs within a 300-kilometre radius of Delhi, it does not spell out concrete measures for retrofitting, upgrading or phasing out existing plants currently operating in the region. This omission is significant, given that TPPs fall under the broader “industry” category—one of the largest contributors to both primary and secondary particulate pollution.
“Thermal power plants are included in combined assessments, but the report does not clearly explain how regulatory responsibility will be assigned to these large sources,” said Nivit Kumar Yadav, programme director, industrial pollution unit, Centre for Science and Environment (CSE), New Delhi.
The lack of clear timelines further weakens the implementation framework. Although the report outlines several “long-term measures” across industry, transport and dust management, the accompanying tables do not indicate firm completion dates or measurable milestones. While stakeholders have prepared annual action plans for 2026, the broader long-term goals are described as “continuous” processes, raising concerns about accountability in the absence of time-bound targets. “Clear timelines are essential to ensure that proposed measures move from planning to implementation,” Yadav added.
There is also uncertainty around immediate enforcement pathways. The report places strong emphasis on future analytical and modelling tools, but offers limited clarity on how existing regulatory mechanisms will be used in the interim to address known emission hotspots and cases of non-compliance.
Finally, the report does not assess institutional capacity. While it calls for strengthened monitoring and coordinated enforcement by pollution control boards, it stops short of evaluating current staffing levels, monitoring infrastructure or enforcement readiness — factors that will ultimately determine whether the proposed measures can be effectively implemented on the ground.
Court oversight to continue
The Supreme Court has not set any deadlines for implementation and is expected to continue monitoring the matter as CAQM develops its proposed frameworks. Much will depend on how quickly these analytical exercises translate into clear, enforceable and time-bound action.