New Delhi: Lucknow has topped the fifth Swachh Vayu Sarvekshan 2026, which ranks India's cities on measures taken for air quality improvement while national capital Delhi sits much lower at rank 30 with Mumbai & Bengaluru even further down.Odisha made a big mark among smaller cities in the rankings announced on Monday. The survey assesses cities on action taken on road dust, solid waste management, vehicular emissions, industrial pollution, C&D waste management, other emissions (DG sets and commercial setups) and awareness activities.Indore, Jabalpur and Bhopal...Lucknow topped the chart among cities with a population above 10 lakh with a score of 198/200, pipping last year's topper Indore narrowly. Indore, Jabalpur and Bhopal held the second, third and fourth slot, respectively, firmly establishing Madhya Pradesh's credentials at concerted effort in air pollution control. Agra in Uttar Pradesh was tied at the fourth place while Surat came next.Delhi improves to rank 30: Delhi, often described as the world's most polluted capital for its high Air Quality Index (AQI) scores, was ranked at 30 with a score of 172/200, while the country's financial capital Mumbai is even lower at rank 37 and Bangalore at 41. Hyderabad was ranked 27.Odisha callingAmong cities with a population of 3-10 lakh, Odisha's Rourkela led with a score of 198.5 while state capital Bhubaneswar was at the fourth rank. Firozabad (UP) and Guntur (Andhra Pradesh) tied for the second place while Amravati was third and Delhi-adjacent Noida at eighth. In the rankings on cities with a population of under 3 lakh, Kalinga Nagar topped, followed by Angul and Talcher. All three are in Odisha.Ward-wise listing: The first ever micro-ward competition saw Ward 70 of Lucknow municipal corporation leading the charts followed by Ward 60 of Bhopal and Ward 7 of Nashik.Eight-year haulBetween 2017-18 and 2025-26, 108 out of 130 cities covered by NCAP have shown improvement in PM10 levels. With 72 of them reducing PM 10 levels by more than 20%.