In Chhattisgarh, Raipur-Durg-Bhilai (RDB) tri-city area hosts the new administrative capital of the state, interconnected by an expressway forming the industrial corridor and is one of the largest steel manufacturing hubs in India. Between 1998 and 2016, the satellite and global model data derived concentrations show a 50% increase in the overall PM2.5 pollution in the region. The average PM10 concentration measured at commercial, industrial, and residential monitoring stations is 125 ± 52 µg m-3 in 2015. None of the stations currently measure PM2.5. The annual average PM10 concentrations in 2011 is 175 ± 110 µg m-3, which translates to 28% improvement in 5 years. A multiple pollutant emissions inventory was established for this urban airshed (extending 60 km x 30 km), with annual estimates of 41,500 tons of PM2.5, 59,650 tons of PM10, 7,600 tons of SO2, 67,000 tons of NOx, 163,300 tons of CO, 118,150 tons of NMVOCs, and 3.1 million tons of CO2 for 2015, and further projected to 2030 under business as usual conditions. The ambient source contributions were calculated using WRF-CAMx chemical transport modeling system, highlighting the heavy industries (mostly steel) (23%), followed by transport (including on road dust) (29%), domestic cooking and heating (12%), open waste burning (6%), as the key air pollution sources in the urban area. The city has an estimated 26% of the ambient annual PM2.5 pollution originating outside the urban airshed - this contribution is mostly coming from the coal-fired power plants, large (metal and non-metal processing) industries, and brick kilns located outside the urban airshed and seasonal open biomass fires.